REVIEWED 11 'SCANNERS' WORLD -NEW BEARCAT
ELECTRONICS TODAY INTERNATIONAL
JULY 1983 $2.35"NZ$2.75 a I
TO BUILD DICK SMITH'S VZ200 PUSHING DOWN THE PRICE OF PERSONAL
, COMPUTING MAGNETIC 11 orpo E SCIENTIFIC MYSTERY
`POWER DOWN' MAINS APPLIANCE
TIMER . GENERAL PURPOSE AUDIO AMP PROJECT flRIF'i_ . 0711:HIS INTRODUCING THE REVOLUTIONARY NEW MARANTZ COMPACT AUDIO DISC PLAYER.
IGITAL AUDIO, the greatest improvement in music reproduction since the birth of stereo is now available to give you sound more pure than any you have previously heard. J THE MARANTZ CD EXPERIENCE. It's dramatic. And instant. Plug the Marantz Compact Disc Player directly into your existing system and it immediately upgrades the sound-limited only by the performance of your current equipment. You can expect astonishing channel separation. Very precise spatial imaging. Sensational dynamic range. Rich bass notes. Pure true treble. And, because the encoded music is read by non -contact laser-absolutely no background noise and no disc wear. MARANTZ FEATURES. The Marantz CD73 is gold toned. Elegant. Simple. The control panel is clean and neat, with LED signals to indicate function and track selecticrn. The highly sophisticated technology is push-button operated. The disc drawer glides with the smooth precision of electronic control. Marantz is control convenience. And technologically, Marantz uses a special integrated circuit with three functions (oversampling, a transversal filter and noise -shaping) which processes the original signal through various stages to give a dynamic range of 97dB. This amounts to a 1dB improvement over most other systems. You may never hear the difference. But Marantz cared enough to make their Compact Disc Player demonstrably closer to perfection. IS THE MARANTZ CD73 REALLY ANY DIFFERENT? David Prakel for Hi Fi Answers magazine (UK) who did hear the difference said: "I have been' surprised by the quite audible difference between different CD players and have already stated a preference for the sound of the Marantz machine in terms of its handling of 'ambience' and its sheer unfatiguing listenability. Other players I've heard in direct comparison have shown a bright veiling effect with more up -front presentation and a fatiguing quality." COMPACT Hear the CD73 for yourself. Call our local office for your dUÍ nearest Marantz Dealer or write for further information. í1:i1 DIGRAL AUDIO
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iY- HEAR. Ido EVI'I MARANTZ (Australia) Pty. Limited Inc. in NSW, 19 Chard Rd., Brookvale. NSW 2100. Sydney (02) 9391900, Melbourne (03) 544 2011, Brisbane (07)446477, Adelaide (08) 2232699, Perth (09) 2763706, Townsville (077) 722011. advertisers features 10 The Magnetic Monopole Mystery Predicted to exist but not yet found Australian 99 Op -Amp Cookbook ETI's practical guide to these versatile ICs Government 34,35 projects and technical Ampec 36
Altronics 72,73,82,83, 68 166: Function -Pulse Generator 1 Hz to 1 MHz 92,93,98 71 1520: Wideband Amp Output amp for the function generator AED 55 78 464: General Purpose Audio Amplifier Ideal for the loudhailer 85 465: Loudhailer Make yourself heard Billco 133 90 265: 'Power Down' Mains Appliance Timer Turn off that light C&K Electronics 62 99 Op -Amp Cookbook ETI's practical guide to these versatile ICs Commodore 26,27 132 Lab Notes: Some CMOS Circuits Don't Always Work Here's why Dick Smith 138,139,140 134 Ideas for Experimenters Parking light reminder, flasher, distortion unit Daneva Control 55 144 Shoparound Where to buy kits, components, pc boards and panels for projects Electronic Agencies 57 computing today Elmeasco 97 25 Spectravideo SV 318 Personal Computer More competition Emona 62 32 VZ200 Reviewed Dick Smith's personal colour computer Ferguson 18 39 Graphics Driver for the ETI-640/685, Part 2 The real thing in graphics G.F.S. 142 49 'pfs: Graph' Reviewed Graph routine for the Apple business user Hitachi Denshi 50 52 '660 Software TV message maker/inventory, memory display utility !mark 50 56 Microbee Column Use your Microbee as an audio frequency counter
Jaycar 6,7,66,67,76,77, 58 VIC-20 Column " A 1.5K game, music generator 60 88,89,135,136 ZX Column Prints text in upper and lower case, encode text or data K-Nar 45 sight & sound Magraths 61 20 Jamo CBR 1703 loudspeaker reviewed Four-way Danish speakers Marantz IFC National Panasonic .... 12,13 news SCAAEERSMCViLD-NEYBEA/K'A, REVIEWED ] Nicholas Kiwi OBC
e;\TODAY Pioneer 17 8 News Digest iELECTRONICS 15 News ttr- Pre -Pak 51 Sight and Sound INTERNATIONAL 28 Printout Rose Music 155 63 Equipment News LOUDHAILER Rod Irving 4,38,46,47, DICK SMITHS 64 Component News VA 200 as.ncDO. V 48,54,84,96 Pit 141 News a Communications ccwmnwc Radio Despatch 65 142 Scanners' World MAGNETK Mans+44.eá Scientific Devices 131 contests and Software Source 29,31 special offers SME Electronics 41 Sony 19 137 Idea of the Month Contest RA.'RDDI 4 MAPS lr4 MACE Truscotts 87 $90 prize to win 05.N1A2. PwntsE AIDVAhpRRpkCt Vendale 60 Video Active 24 Stand out among the crowd - with the general ETI-465 Loudhailer!
Cover design by Ali White 145 Mail Order Books 153 Mini -Mart Registered by Australia Post - 154 Dregs Publication No. NBP0407 ISSN No. 0013-5216
ETI July 1983 - 3 ALL KITS LESS 10%. OFFER ENDS JULY 31, 1983 ROD IRVING ELECTRONICS 425 High Street, Northcote 3070,. Melbourne, Victoria. Ph (03) 489 8131. Telex No. 38897 48-50 A'Beckett Street, Melbourne. Ph (03) 347 9251 N --1,11C I- kits this month P ETI 465 N Loudhailer N Now you can o e make yourself = heard at the D N ETI-464 Audio Amp Module local football ETI-1520 Wideband Amp Module match of the Every hobbyist . should build at Never mind the low cost, just look next anti- ETI-265 Power Down Mains least one! This simple project can at the specs! Bandwidth of 5 MHz nuclear rally. 7C N Appliance Timer be built in quick -smart time and (-3 dB), delivers 10 V peak -to - Simple, yet .. has a host of uses - in an in- from V effective, it Cl) Push the button to turn your ap- tercom, as a baby minder, to power peak into 50 ohms +/-15 gain, distor- uses the pliance on, this turns it off automat- a loudspeaker from your crystal supply, 20 dB 0.03% improving CRO ETI-464 amp ically some convenient time later. set. Will deliver up to four watts tion, etc. Ideal for Simple to build, low in cost. sensitivity, as a video amp, etc. module. H output. I- TV PATTERN GENERATOR BIPOLAR TRAIN CONTROLLER MIXER PREAMP $64.50 EA December 80 $34.50 TRANSFORMER r :t
TV PATTERN GENERATOR 1-' C : : i ¡ J . s t'J) I- 4 Adjust your TV for a hrshclass picture with EAs crystal Y controlled TV Pattern Generator EA June 80
.. Easy construction and versatue operation, this Preamp was f WIND for coupling with the 300W "Brute" Power Amp. ETI 467 October 81 July 80 SPEED $52.50 fN lei INDICATOR AUDIO TEST UNIT FOR CASS PC BIRDIES $14.50 4110 DECKS $47.50 U)
i J ,... N i TRANSISTOR ASSISTED
IGNITION Granny's Birthday - PC Budics. EA November 79 Grannys got a brrthday coming up and you don't know what X to give her! Her cat ran away, her dog starved and the fish EA October 81 turned upside down. Well here's the perfect gift. A no- nonsense, no mantenance companion The PC Birdies - Cl) She'll whretle, sin° and dance for hours to this amazrno Y electronic canary EA May 81 '
D
$34.50 CRYSTAL MARKER $34.50 N ETI 477 MOSFET (INC 1MHZ X) ET1157 October 81 MUSICOLOR IV $84.00 MODULE $63.50 otl 157 CRYSTAL MARKER N MUSICOLOUR IV II _ .,' {Ja #1:. .. 'i 1
/ r c . -_ Add excitement to parties card nights and discos with EAs e y r .. new Musicolcr IV light show This is the latest on the famous Remember the great ETI 5000 power amp With this module line of Musicolors and et offers features such as tour channel as the hub of the ETI 5000 and a transformer you gel an N "Color Organ' plus four channel light chaser front panel amazing power output of 150W RMS t LED display, internal microphone single sensitivity control 1._ Plus Power Supply (No Trans) $49.00 plus optocoupled switching for increased safety EA Plus Transformer 839.50 be August 81 comment next month
THE KUIPER OVER THE PAST few months, following a change of ownership AIRBORNE OBSERVATORY and a traumatic move of the complete office and laboratory to a IN AUSTRALIA new location, publication of the magazine has got a little 'off the Editor you like your regular 'hit' of electronics/computing/ A Lockheed L-300 jet transport aircraft, rails'. If aperture telescope is Roger Harrison VK2ZTB month and haven't been able to enjoy fitted with a 36" communications/audio every operated by NASA to provide scientists it when you've come to expect it, then we apologise. However, from Editor with a very special infrared observatory. Technical we'll be on rails again with maybe just the odd David Tilbrook VK2YMI next month back the The telescope is carried to heights of loose wheel' to fix. 12 km (40 000 ft) to get it above 90% of the earth's water vapour, which absorbs Assistant Editor A serious hiccup in the distribution in New Zealand earlier this Jennifer Whyte B. App. Sc. infrared rays. This craft carried out a year has alarmed a great many loyal New Zealand readers. That series of observing flights for Australian Editorial Staff problem was outside our control but has now been fixed. For good, scientists in May and June. Jennifer Geoff Nicholls B.Sc./B.E. we hope. Whyte tells the story. Jonathan Scott B.Sc./B.E. (Hons) VK2YBN In this column last January, I said we'd be introducing new features during the coming year. The VIC-20 computer column, Draughting SEVEN PERSONAL David Currie introduced in April, is well under way, the new Scanners' World column, introduced last month, is off to a good start and this STEREO CASSETTE PLAYERS Advertising Production month, we have a 32 -page Op -amp Cookbook for you. We intend to REVIEWED John Gerrie include more cookbooks in future issues and, if the response is what we expect it to be, they'll become a regular feature. A sort of 'across the market' review of Advertising Sales seven 'famous name' personal stereo Bob Taylor (Group Manager) Stick with us, we've got yet more goodies in store! cassette players - we give the facts on John Whalen (National) how they measure up. Are they hi-fi or low -fi? Find out next month! Art Staff Ali White B.A. Bill Crump Githa Pilbrow DEVELOPING THE MPF-1B MICROPROFESSOR Reader Services Jane Nicholls Here's one for the hackers! Ever wanted Roger Harrison an alphanumeric character set for your Acoustical Consultants MPF-1B? No problem - in fact, you ' Z Louis Challis & Associates Editor have a choice of a limited 32 -character set or a 64 -character set. Sorry, no pre- prints, you'll just have to wait till August! Advertising Offices and Agents 11 New South Wales: The Federal Publishing Company, 140 Joynton Ave (PO Box 227), Waterloo NSW 2017. Phone: (02)662-8888. services Telex: 74488 FEDPUB. 'SCREEN SPOTTER' Victoria and Tasmania: The Federal Publish- LIGHT PEN FOR THE ing Company, 23rd Floor, 150 Lonsdale St, Technical enquiries: Wé can only answer readers' technical enquiries by Melbourne Vic. 3000. Phone: (03)662.1222. telephone after 4.30 pm Mondays to Thursdays. The technical enquiry MICROBEE Telex: 34340 FEDPUB. number is (02)662-4267. Technical enquiries by mail must be accompanied by South Australia and Northern Territory: a stamped, self-addressed envelope. There is no charge. We can only answer Just what all you 'bee bugs have been The Admedia Group, 24 Kensington Rd, Rose queries relating to projects and articles as published. We cannot advise on waiting for! This simple, low-cost device Park SA 5067. Phone: (08)332-8144. Telex: modifications, other than errata or addenda. We try to answer letters as soon plugs into the 8 -bit port and operates in 82182 ADMDIA. as possible. Difficult questions may take some time to answer. the lo -res mode (that's because a hi -res Queensland: Geoff Home Agencies, 16 Bell- light pen is 100 times as difficult, and a bowrie Centre, Bellbowrie Old. 4070. Phone: General enquiries: For enquiries about back issues, photostats of articles, lot more expensive). Software listing is (07)202-6813. artwork or submitting articles, call (02)663-9999 or write to the address on included. Western Australia: Cliff R. Thomas, Adrep this page. Advertising Representatives, 62 Wickham St, East Perth WA 6000. Phone: (09)325-6395. The publisher accepts no responsibility for unsolicited manuscripts, or photographic matetial. New Zealand: Steve Edgar, Collector Publi- illustrations cations, GPO Box 7118, Auckland. Phone: COPYRIGHT: The contents of Electronics Today International and associated publications ETI-166 FUNCTION (02)54-6380. Telex: 21217 ARCHCOL. is fully protected by the Commonwealth Copyright Act (1968). AND PULSE United Kingdom: Peter Holloway, John Copyright extends to all written material, photographs, drawings, circuit diagrams and is breach we Fairfax and Sons (Australia) Ltd, Associated printed circuit boards. Although any form of reproduction a of copyright, are GENERATOR for their own private nor Press House, 12 Norwich St, London EC4A- not concerned about individuals constructing projects use, by pop for in with 1BH. Phone: (01)353-9321. Telex: 262836 groups (for example) constructing one or more items use connection their Now you can get into the guts of the SMHLDN performances. project. Any electronics workshop part in Japan: Genzo Uchida, Bancho Media Commercial organisations should note that no project or project described worthy of the name needs a good func- may be offered for sale, or sold Services, 5th Floor, Dai-lchi Nisawa Building, Electronics Today International or associated publications tion and pulse generator- this means or fully assembled form, unless a licence has been specifically obtained so 3-1 Kanda Tacho 2-chome, Chiyoda-ku, In substantially you. All the functions and features you to áo from the publishers, The Federal Publishing Company, or from the copynght holders. Tokyo 101. Phone: (03)252-2721. Telex: could wish to want. Another project in 25472 BMSINC. LIABILITY: Comments and test results on equipment reviewed refer to the particular item the David Tilbrook lab -standard' series. may not necessarily pertain to other units of the same make or Electronics Today International is published submitted for review and Whilst has made to ensure That all constructional projects by The Federal Publishing Company Proprietary model number. every effort been will operate as indicated efficiently and properly and that all Limited, 140 Joynton Avenue, Wate9oo NSW referred to in this edition will be no responsibility is 2017. (02)663-9999. Telex AA74488 necessary components to manufacture the same available in respect of the failure for any reason at all of the project to operate effectively or 'FEDPUB'. This issue was printed by ESN, accepted Although these articles are in an fault in design or and no responsibility is accepted for the The Litho Centre of 140 Joynton Avenue, at all whether due to any otherwise in respect of such project. Further, no advanced state of preparation, circum- Waterloo NSW 2017. (02)662-8888. Distnbuted failure to obtain any components parts any any fault in the stances may affect the final content. by Gordon and Gotch Ltd. responsibility is accepted in respect of any Injury or damage caused by design of any such project as aforesaid. The Publisher accepts no responsibility for However, we will make every attempt to material. ' Recommended retail price only unsolicited manuscnpts, illustrations or photographic include all features mentioned here.
ETI July 1983 - 5 Bi'eal ii 'resins In all states and territories in Australia it is an offence to drive avehicle with an alcohol/ blood concentration above a certain limit. In most states it's 0.05 others 0.08. Either way it's only a relatively small number of alcoholic drinks. Because it's only a small number of drinks, many people (quite wronglyl believe that they remain below the statutory limit. The KA1522 Breath Tester can help here. A unit with the same circuit diagram was featured in May "Electronics Australiai'. It CANNOT give you an actual blood/alcohol content reading, however it can go close. And it can give you a relative reading between inebriated friends!!! Great at parties!!! Grab the whole kit now for only 529.95. You never know, it may save your licence or your life(
Valuable IC Inserter ,Tien you buy ANY KIT andror ANY Maloeder from Jaycar for the month of JULY. That's right Whether yea pay S4 or 5400 fora kit you are entitled' Quantities are strictly limited and if stocks run out well, we're sorry. We will not be alee to obtain any more after stocks go. Here's the catch. To qualify, all that you have to don tell us in which nag use yea saw this ad. We want to measure the effectiveness of each nag s2995 mine and this is our way of thanking you for helping us. (' Note: Offer is limited to one per customer for July. Personal shoppers will receive one FREE if they buy any KIT. ALL Mailorder customers will receive one until stocks run out).
Ref: EA April 1983 Complete kit including quality HPM wall plate with atteactive brushed metal insert. The Jaycar kit is absolutely complete including a small dial spring which can be used to connect the PCB to 1 the wall plate. (Beware of other kits that do not include this!. E,N In we Sensitive addition to the above. supply the High Voltage Resistors ALREADY SOLDERED in as a foolproof safety feature! Buy the complete kit for this exciting protect for only Cat. KA.1508 only S 1995
Follówing the.spectacular success of the DP2010 Digital Multimeter kit, Speohc.hon we now have an ENGINE ANALYSER KITI Function F 5 D Resol"non Ace uracr Monitor 1 209 10 MI 05 Idya But the spectacular thing is the is h., price) It ACTUALLY CHEAPER 200V I00in0 O5 1 digit than the DPM-05 Display and Case!! Resistance 700(1 IttOti O 05 I clot The Minitune will measure voltage, resistance (down to every low 20.0 10[) 0 5 1 d, range), R P M 20 000r pn 10r inii 1 3.1.#i. RPM and Dwell Angle. Dwell 90 01 7 7ib, Cat. KJ7012 MINITUNE KIT $42.95 TEST LEADS TO SUIT ONLY $2.95 FAR CHEAPER THAN DPM SEPARATELY
vv 50V/5A laboratory Ref: EA May/June 1983 power supply By far the most exciting high power supply we have seenl Using the latest switchmode principle, very little energy is wasted with Ref: high dissipation in the regulators - a cause .2 of considerable heat dissipation and high EA hardware costs. June The Jaycar kit comes with every originally 1983 specified component down to the last nut and bolt Also included are special Scotchcal meter scales. Beware of Inferior kits that do not supply such components. (Not for sale 54,95 as a separate Item). Cat KE1520
eti162POWERsu7k 3 ETI 162 Ref: ETI December 0-30V lamp 1982 4'1 cy power supply 50 Cat KE4570 $49 EA dual tracking PIS Extremely versatile power supply: WIII give plus & minus 1.3V to 22V - Fully protected 0e1 EA March .02 at up to 2 amps PLUS A FIXED - Output variable from 0-30V DC aa h..naa,,,.t..ae,. Cat KA1410 [email protected]. The supply is comp- - Selectable current limit -- a ` letely protected against short - Both voltage and current metering circuits, overloads and thermal - After a multimeter & soldering Iron an P runaway. A large meter with absolute must for the enthusiast. voltage Is as You will never own a more useful piece of e I calibration supplied } well as IC sockets. A quality kit gear.
6 - July 1983 ETI 500MHz Function Generator Ref: EA April 1982 Digital Frequency 121438111 .Ka + l St,, c--: * INN,. Period Meter - a"Po " Cat KÁ1428 Ref: EA Dec'81 - Feb '82 u.s, FREE. TILTING Jaycar °$. _ BAIL WORTH has by far the best kit version '7 of this FUNCTION GFAEAA7On ,C .I 54.95 included project in Australia. We now supply 2 x GOLD plated BNC input connectors at no ONLY extra costl "Pigeon Pair" companion to the new 500MHz DFM. Low distortion Cat generator KA1390 $119 (50MHz Version) of sine, square and triangular waveforms. From below 20Hz Cat KA1392 to over $26 (500MHz option) 160kHz. Inbuilt 4 digit frequency counter in de-luxe 'case. (Beware of kits that don't conform to the original design). JAYCAR EXCLUSIVE - 1% 50ppm metal film resistors used for stability TRANSISTOR ASSISTED IGNITION. BBD EFFECTS BOX Fantastic low-cost instrument using the ver- Ref: EA Jan '83. Latest satile MN3001 Bucket -Brigade Delay line to COMPLETE version of this popular achieve brilliant sonic effects. KIT kit The Jaycar kit has a Now you can emulate the commercial rock LJ 13 ETS utº rT genuine die cast box - groups with Phasing, Flanging, Reverb and Cat K E 1522 as used in the EA pro- s ' Echo. The Jaycar kit includes all components $79.00 totype. Beware of INCLUDING IC sockets and the TU -04 box. others that use flimsy h1á)Ii (Not cut down but this is easily done). sheet metal. Jaycar has a specially built cabinet for this Special Cat P e kit with all cabinet KA1506 $35 _ f holes pre -punched etc., at only $10 extra but only if you buy the original to suit $10.00 rWY. Rt. _- rh kit from us. Available as a separate item for magnificent! $29.50. Cat H66445
JAYCAR - FIRST IN AUSTRALIA LOW COST DIGITAL WITH THE VERY LATEST IN THE ROBOTICS FIELD OF ROBOTICS MULTIMETER KIT Jaycar is the lint major electronics company In Australia to sock BY POPULAR DEMAND useful-1 robob In kit and ó.95t-up form. '.lo 1.10 Up .01111 new nr. fine Set 01 ten, Proles lo 1111. f* *11 $2.95 E(i..y+o Probe to A w7l COL 51í2 Li MOO ONLY 52.50 E.ertadt 216 Fred) `Cie> 9V Battery CaL SB2370 ONLY 51.40 no? ONLY DP2010 k5 C. KJ7010 ONLY 545 AC VOLTAGE AND CUtiRaN T RANGES Ja wRRac. n wallop 1.0.0 .1110r $499 * * SPECIFICATIONS n.,M e . a«Al n11010 e 'm e am nVOcoNPoltD.a Funetlm I.IA. Resdut,on Accuracy Protection Vol?, 200V 100mV 215'5 dgt Rn e ..n..m..Aile Id.e.1 2V lmV 5006 1V O°O.sí10. 01 any O. 1101.:':...`: .e.-.w.onlil.. 1%1 0.011 500V lo, 2515d.pt o. IOU *welch waslyei local ant 20V 1anV 1%_1áq1 one mom» Current 2mA 1oÁ 21150105 141250V 2005 100m 1%I d,qt In.c.l 20mA 10uA M5 dead 5005 1V 20U1nek MICRO GRASP Cl? INCLUDING POWER 1%'1 dive 100,Á 0%5 d.gt SUPPLY CO. KRI000-SPECIAL NTRODUCTORY MICE f4ºº W Current 1uA UNIVERSAL COMPUTER INTERFACE 2mA 1%'l alpe 1A/259V 2000mA 1mA 7%5 dept ROARO1,. IanIomlCal KP1010 ONLY 51.90°Ism fw51a. 2Ka1 73 2J Nay nag cone.mto an ,...e.4lea .o.nwl.1 Id.e.l 70mA 10uA 11111 Resistance 2K 1 far 2R EI Re. o'.ral/RAM Pea %PPn., e.e.O S ID95 No I%ldge 260V CALL IN TO 700mA 100,A OUR YORK SERE E f SHOWROOM AND SEE WOR RINGII 3% 1 dpi 20K 10 1% 1 dogt 1m.s. 2000o'A lmA 5%1 d.gl 200K 100 1% 1 d.Ril AS DESCRIBED Volt, Wei 2V 11,5 25'S duet 500V for 2000K 1K 1% 109.1 ETI MAG. APRIL/MAY 1983 O.ode 206 10mV 2%5 Mgt one m.o.' Test 2V 101V 1% 1 rheía 2606 , e...5. DIGITAL HEART RATE LO51ITO CAPACITANCE Digital urn' METER I rawns 1119 I Thermometer 9 Ref: EA July '82 $7450 Brilliant kit which enables you to measure your heartbeat instantly. One of our most Ref: EA Feb '82 popular kits ever. The Jaycar kit comes in a Ref: EA March '82 beautiful 0 - 100 degrees C with 0.1 degree resolution. ABS spiashproof case with profes- Accurately measure capacitance from 1pF Bright, sional silkscreened panel. - easy to read display. Kit includes 19.99u F. A must for the serious enthusiast two temperature Cat KA1466 $79 sensors. Cat KA1420 $74.50 Cat KA1404 S74.50 STEREO STEREO STEREO STEREO Creates a very realistic stereo sound from mono 1iJ eTpEO STNtIR915511 sources i.e. AM tuners, TV or video units. Very i 1-JAYCAR easy to build and comes ,p Synthesiser w SEE THE OTHER JAYCAR ADS Cat KA1476 complete. Only Cat KA1478 ONLY IN THIS MAGAZINE FOR OUR Short STORE Form Version $49.50 ADDRESSES AND $39,50 Ref: EA September 1982 PHONE NUMBERS.... ETI July 1983 - 7 Channel 9 busted over unlicensed microwave equipment Two television stations, Consolidated Press Holdings Ltd's Channel 9 in Sydney and Bris- bane station QTQ-9, owned by AWA, have had summons issued against them for the alleged use of unlicensed microwave links between Sydney and Brisbane. the basis that it was a Federal The Federal Department of The department claims the two wireless telegrapy". were links in a chain, The Act prescribes a penalty of matter. Communications, which is- stations 9 has been sum- both authorised and five years' imprisonment or Channel sued the summons, seized comprising monsed to appear in the Federal microwave equipment on unauthorised stations, which $1000 fine. Section 7 says such unauthor- Court on July 11 for a hearing. June 3, following investiga- provides an alternative unoffi- depart- television ised equipment shall be forfeited In a separate inquiry, tions by officers from the cial route for some understood to between Sydney to the Commonwealth. ment officers are radio frequency management transmissions be investigating unauthorised and Brisbane. It was alleged that Neither the Federal Depart- division. nor microwave links between con- these stations had no purpose ment of Communications the The seized equipment 9 Sydney and Melbourne. microwave stations; other than transmitting tele- Station Manager of Channel in sisted of two would on the Investigations claim to show been set up at Somersby vision programmes between Sydney comment one had matter. evidence of a temporary system on the NSW central coast and the north and south. short is The department launched its which could be set up at other was at Coolangatta, just The Government's action ta- micro- Wire- seizures after talks with the De- notice with towers and over the Queensland border. ken under Section 6 of the but with no bans puty Crown Solicitor's offices in wave dishes in place The Government acted on this less Telegraphy Act which receivers in- establishment, Sydney and Brisbane. The transmitters or matter because it doesn't want the unauthorised stalled. links to erection, maintenance or use of Queensland action was taken telecommunications of State police, So far there is no evidence that sidestep Telecom, unless the "any station or appliance for the with the support NSW police refused to these links have been in un- for Communications purpose of transmitting or re- but the Minister in the NSW action on authorised operation. authorises otherwise. ceiving messages by means of take part Twelve years, 147 ETI issues, síx overseas editions, six new magazines, and it's time to move on .. Founder -editor of Electronics Today International (ETI), Collyn Rivers, and his technical -editor wife Jan Vernon have left the publication and its now world-wide associated editions. Jan and Collyn have started a assignments for a number of technical writing and publishing trade and professional organisa- !- company, Vernon, Rivers & tions in the computing and gen- Associates Pty Ltd, 18 Clifton eral technical industries. Lane, East Balmain NSW 2041. Planning is also apparently Among other activities well in hand for a new technical Vernon, Rivers & Associates will publication due to be launched be preparing business computing within the next three months. and general technology features Electronics Today Inter- for the Bulletin, Australian Bus- national, Collyn's original publi- iness, and the monthly general, cation, was owned by Murray software and equipment news Publishers before its acquisition sections of the recently re- by the Federal Publishing Com- designed Australian Computer pany division of Eastern Suburbs Society Bulletin, and other publi- Newspapers earlier this year. cations worldwide. Further info: Collyn Rivers The organisation will also be (02)818-3559. undertaking specialised writing 8 - July 1983 ETI NEWS DIGEST Electronic night fishing The Matsushita Battery Company (National Panasonic) Z of Japan has been producing very small, light -weight . . batteries since 1978 with thicknesses down to 0.7 mm. ` . Recently they have employed required to maintain the glow for lithium to obtain a higher energy an adequate time, yet the bat- density and this has resulted in a teries must not be large enough new application. to alarm the fish. Lithium paper A fisherman's float using one cells, nominally 3 V, with a of these batteries connected to a diameter of 4.2 mm and a length 1 light emitting diode can be used of 26 mm weighing only 0.5 g as an imitation glow-worm. It is offer a 20 mA-hr capacity. A cell claimed that fish will bite at the of the same diameter and 10 mm For hot fingered plated tips. glowing diode which (when fitted in length has a 40 mA-hr cap- interchangeable tips come The with a suitable hook) results in a acity and is said to be able to solderers sizes and the and in four tip much greater catch than would attract fish for a period of at least barrel are fully earthed for com- Scope Laboratories now otherwise be obtained at night! 4 hours. ponent protection. offers a mains voltage 20 W A reasonably high capacity is is to be B. Dance non temperature controlled Trade price expected around $15 in most states (tax iron. extra). Innovative lead -acid battery design It features an air insulated For further information contact Assistance to Inventors grip, which helps keep the fingers Scope Laboratories, 3 Walton Under the Federal Government's cool during continuous soldering, St, Airport West Vic. 3042. Scheme, James Mackaness,an engineer ofCheltenham and long life anti -corrosive iron (03)338-1566. (New South Wales) has received $10 000 to manufacture prototypes of a new lightweight lead -acid battery. Mr Mackaness designed the This not only reduces the weight, battery after discovering that but improves the charging and almost half the lead used in discharging rates. conventional batteries was While the battery's main mar- wasted. By using much finer lead ket is presently in the vehicle for the conducting function, and industry, it offers a number of substituting polypropylene for new applications, particularly the structure, he was able to for portable tools, machines, C reduce the wasted lead by 70%. lighting and electronics. Known as a lead -acid automo- Further details are available 1 tive (LAAUTO) battery, Mr from Eric Hunter, Director of Mackaness' design also elimin- Public Relations, Department ates the need for the heavy - and of Science and Technology, expensive - lead grids used in Canberra ACT 2600. (062) conventional lead -acid batteries. 64-4145. Self-help for handicapped people Prototypes of FRED (Friendly Education Device), a new training aid for handicapped people, are currently being manufactured by Thorn -EMI Electronics Australia. The tested product is expected or rehabilitation programs at to be commercially available their own speed and can be used The pick of pliers soldering. Cat T-3325. within the next 18 months. by people with mental or physi- The s/s mini needle nose plier A portable, microprocessor - cal handicaps, as no technical Dick Smith has a brand into small spaces based training unit, FRED is knowledge of the equipment is new range of four directly is for getting and working with small com- designed to be connected to a required. imported stainless steel as is to cost ponents 1 ike DS549s. Cat T-3570. television set in the same way The unit expected high quality pliers. The s/s mini long nose plier can computer -based television between $1 200 and $1 500 and The s/s transistor nipper, super be used in 'rat's nests' of wires, games. It uses computer -gener- further information is available sharp with a long life cutting great for pulling components out ated programs to provide dis- from Eric Hunter, Director of edge, is ideal for pc board work. of tight spots. Cat T-3565. plays on the television screen, Public Relations, Department Cat T-3205. The pliers are priced at $7.75 which a handicapped person can of Science and Technology, The s/s mini flat nose plier is each and are available from all control with a lever or joystick. Canberra ACT 2600. (062) also for working on pc boards and Dick Smith Electronics stores FRED allows handicapped 64-4145. can be used as a heatsink while Australia -wide. people to move through training ETI July 1983 - 9 Magnetic monop Ins a scientific mystchl Single north and south magnetic poles are predicted to exist but haven't yet been found. Could this be because of their unex- pected properties: massive, slow -moving and rare? Jennie Whyte FOR MORE THAN 50 years physicists have been looking for magnetic monopoles, elementary particles which carry a single magnetic pole. They are predicted to exist but so tar no one has produced enough conclusive evidence of an observation. A new theory explains that this may be because the mono- poles are too massive, slow -moving and rare. Blas Cabrera, a researcher at Stanford University, thought that he might have found one early in 1982. But he has yet to verify an effect he has observed only once in six months. Theory suggests that there are Dipole fields. Set up by a bar magnet. Magnet cut in half. Two smaller dipoles are created. not enough monopoles around today to exp- lain why one should have been found in such a relatively short space of time. As early as 1269 Petrus Peregrinus, a French investigator of the magnetic proper- ties of materials, noted that magnetic objects have paired regions of opposite polarity; that is, all magnets are dipoles. It seems that magnetic 'charges' or poles always occur in pairs, unlike electric charges which can oc- cur as isolated positive or negative charges. If you cut a bar magnet in half you end up with two smaller magnets, each with a north and south pole, rather than two pieces with An electric structure analogous to the above. Op- Electric analogue cut in half. The field remains opposite poles. This is because every in dipo- atom posite electric charges are deposited at the ends. lar because the electric charges that generate the field a magnetic material behaves as a tiny remain in place. magnet, each atomic field being generated by electrons orbiting the atomic nucleus tjust charge must be quantised everywhere. Until electric charge approaches the speed of light, as an electromagnet is created by an electric recently, Dirac's magnetic monopole its properties should increasingly resemble current looping round a coil). hypothesis was the only explanation of the those of a magnetic charge. Similarly, a mov- Speculation about the possible existence of observed quantisation of the electric charge. magnetic monopoles has been going on for a Dirac's monopole has a minimum unit of long time. However, in the theory of magnetic charge about 70 times as large as electromagnetic phenomena, formulated by the corresponding unit of electric charge. He James Clerk Maxwell in 1864, the possibil- also predicted that the magnetic monopole ity of isolated magnetic charges was ignored would be matched by a magnetic anti mono- since none had ever been observed. Over the pole. However, his theory made no prediction past century Maxwell's theory has been put about the mass or size of the magnetic mono- to many experimental tests and has never poles, or about their abundance in the been found wanting. That fact alone severely universe. limits the contexts in which magnetic mono- Dirac's predictions stimulated a rush of poles might be found. theoretical papers on the expected properties Interest in the idea intensified in 1931 of the hypothetical monopoles, and several when the British physicist Paul A.M. Dirac experiments were undertaken to detect showed that an important observed property them. Physicists searched for them in parti- of electrically charged particles could be cle accelerators, cosmic rays and even moon explained by assuming the existence of rocks, but with no luck. However, they may single magnetic poles. not have been looking for the right effects. Dirac was trying to explain the quantisation Some interesting properties of magnetic of electric charge; the fact that electric monopoles arise when Maxwell's equations charge appears only in multiples of the of electromagnetism are augmented to in- charge of the electron and the proton. Dirac clude magnetic charges and magnetic Symmetry exists. A north monopole (a) would have showed that if an isolated magnetic pole ex- currents. as its antiparticle a south monopole just ists anywhere in the (b), as the universe, electric For example, as the velocity of a moving proton (c) has as its antiparticle the antiproton (d). 10 - July 1983 ETI ing magnetic monopole would begin to take on the properties of an electric charge at a (a) (b) speed approaching the speed of light. These transformations, which follow from Einstein's special theory of relativity, have been confirmed experimentally for moving electric charges but not of course for moving magnetic charges. A moving electric charge can lose energy by ionising matter; that is, it detaches electrons from their atoms. Because of the much stronger charge of the magnetic mono- pole, it would ionise atoms some 10 000 times more effectively. Thus a magnetic (c) (d) monopole passing through a photographic emulsion of the type employed by physicists to detect electrically charged particles would leave a track thousands of times darker than the track left by an electric charge moving at the same speed. Because the monopole would lose energy to the ionisation process so quickly, it would slow down much sooner on entering a sub- stance than does an electrically charged 0 particle with the same kinetic energy. A magnetic monopole traversing a superconducting coil one metre long would /+ gain more energy than a proton acquires in the largest particle accelerator yet built. Time reversal. In (a) a proton is moving through a perpendicular magnetic field generated by electric currents. If The physics of magnetic monopoles has the direction of time is reversed (b) everything is reversed, the particle retracing its path in the opposite direction. another curious feature which can only be In (C) the magnetic field is produced by an idealised array of north and south monopoles. Reversing time would made apparent by imagining that the flow of leave the magnetic field unchanged (d). Although the proton would reverse direction, it would not retrace its path; a violation of the principle of time -reversal invariance. time can be reversed. This is a thought ex- periment suggested by Robert K. Adair of Yale University. NORTH MONOPOLE PHOTON A proton is in a magnetic field which arises not from an electric current but from the presence of a magnetic monopole. Reversing SOUTH MONOPOLE time does not alter the polarity of the mono- PROTON \\ pole and therefore leaves the direction of the Particle-antiparticle pair. A north monopole and a south monopole could be created when a high-energy magnetic field unchanged. The proton's path photon interacts with an electrically charged particle such as a proton. The mutual attraction between the in the field of a monopole depends on the monopoles, however, would cause them to collide, converting their mass back into photons. direction of time, an effect that violates the principle of time -reversal invariance. of material suspected of harbouring mag- track, presumably of cosmic ray origin, re- netic monopoles is passed repeatedly through a on a stack of photographic emulsions The predicted effects of a magnetic mono- corded superconducting coil. On each pass of a sheets. pole when time is reversed were for many and plastic magnetic monopole the electric current in The detector had been exposed to cosmic years viewed as a serious argument against the coil would presumably increase by a rays while it was suspended from a balloon its existence. small amount. Because coil is super- high for two and a half days. In 1964, however, an experiment was done the flown at altitude incremental induced the detector was at Princeton University which discovered an conducting the current The area -time factor of would persist indefinitely It's then a matter roughly a million times smaller than that effect much like a violation of time -reversal of measuring the extremely small signal in- attained in previous searches in which no invariance in the decay of Ile particles cal led duced by the multiple passes of a single monopole had been seen. neutral kaons. As this finding has become monopole. problems with the monopole better understood some of the opposition to Other By means of this technique Alvarez and interpretation of the event subsequently led the idea of magnetic monopoles has abated. his colleagues were able to show that the the experimenters to suggest instead that Searching north and south density of magnetic monopoles in rock sam- the track might have been caused by the Knowing something of the properties of ples recovered from the surface of the moon is passage of a superheavy atomic nucleus or a magnetic monopoles means that the experi- less than one for every 1028 protons. Even at massive antiparticle. mental search for their existence can take a this limiting abundance, however, there One benefit of this episode is that it ins- more positive direction. Soon after every new could still be an average of one monopole in pired a careful evaluation of how a magnetic particle accelerator is commissioned mag- every 20 kilograms or so of matter. monopole would lose energy through ionisa- netic monopoles are looked for in the debris A less direct way of hunting for magnetic tion. Even so. the question still remains of the initial high-energy particle collisions. monopoles is to look for signs of the creation unsettled. Monopoles have also been sought among and destruction ofa monopole-antimonopole Superheavy particles the by-products of collisions between cosmic pair. In theory a pair of this type could be rays and atoms in the atmosphere. Other created when a high-energy photon passes The prospects for magnetic monopole experiments have tried to detect them near a proton, just as an electron -positron hunters suddenly brightened in the among the atoms of terrestrial and extra- pair is known to be produced. The oppositely mid -1970s as a result of the independent terrestrial substances. Samples of iron ore charged monopoles would exist for only a work of Gerard 't Hooft in Utrecht in the collected from the rocky outcroppings of old moment, however, as they would soon come Netherlands and Alexander M. Polyakov in mountains are another potential source of together and annihilate each other, convert- Moscow. They both found that a certain class material. ing their mass into additional photons. of theories of elementary particle inter- One detection method, first discussed in In 1975 investigators at the University of actions not only allows magnetic monopoles the 1960s, was implemented in the 1970s by California at Berkely and the University of but also demands them. Luis W. Alvarez and his colleagues at the Houston announced that they had dis- These grand unification theories attempt Lawrence Berkeley Laboratory of the Uni- covered a magnetic monopole. Their to unify the four basic forces in nature - versity of California. In their device a sample evidence was an anomalously thick, dark gravity, electromagnetism, and the strong ETI July 1983 - 11 `i---¡------_ D inert Don't tangle with Technics. 2 The majority of audio systems - even the % most beautifully designed - have something ugly to hide. It's that mass of jumbled -up connecting leads that you find, all too easily, at the rear of the equipment. Not only are they ugly, they're inconvenient, too. And as audio components become smaller, the problem becomes bigger and more unsightly. To solve this problem, Technics developed their Direct Connector systems, which eliminate all audio connecting leads between the tuner, amplifier, graphic equalizer and cassette deck. Each of these components features a special flip -up connector to allow them to be literally plugged in to each other! It's an elegant piece of Technics technology that results in a stylish, neat installation that can be put together or taken down for re -location in a matter of seconds. The 315 Series. But Direct Connector capability is not the only innovative feature in this new and compact series from Technics. The SL -5 direct -drive, linear -tracking turn- table employs its own plug-in connector system for the pickup cartridge. This unique Technics development has been adopted as a World Standard. It means you can compare and evaluate cartridges from leading manufacturers like Audio Technica, Ortofon, Shure, Stanton, Empire, Pickering, ADC and, ofcourse, Technics without conventional setting up procedures. Ihiley.?JPAInIL ec mics .ceveo:eE onnector systems. No adjustment of tracking weight or bias Finally, a pair of SB-F5 speakers with horn - correction is needed. type tweeters and bass reflex porting turn the The innovations continue in the rest of the high quality electrical signals of the rest of the components: the SU 5 amplifier includes a Super system into the high quality sound you expect. Bass switch to enhance the bass response of a Compact components, full-size warranty. speaker system without inducing bass boom; the All components in this series are perfectly ST-5 quartz synthesizer digital tuner provides matched in styling and performance.nics random access memory for 16 pre-set stations; And all are covered by a full the SH-E5 graphic equalizer - offers adjustment 2 -year warranty backed by Technics' of 12 audio bands from 16Hz to 32Hz on each reputation. Visit your Technics stockist ,,,,,.Year warranty channel; whilst the RS -5 cassette deck - has soft soon and experience the superb I touch controls, auto selection of metal, Cr02 and styling and brilliant sound of Technics' compact normal tape settings plus convenient Cue and Series 315 for yourself Review functions. Rn.N iús Ñ - Z. 7 íi'i ® i._.., - - ` ----i "'" - -.. a f01.0.'10,,il I -u:' , i 'I< Technics Technics National Palms( mic (Australia) Ptv lid Expanding the music experience. Diley NPAISIR and weak nuclear forces - into one grasp- able mathematical structure. According to this theory monopoles are 'superheavy', 1016 SOUTH times the mass of the proton or ten MONOPOLES nanograms, which is about as heavy as an ' CORE 8o r amoeba. Such a particle is so much heavier than ¡ óoóó 0 any other elementary particle yet discovered clog that it could well explain why previous NORTH searches for monopoles have been un- MONOPOLES successful. Such heavy particles cannot be created at even the highest energies particle accel- S erators can reach, but they could have been trapped in the earth. They tend to collect at two places in the earth's core near their opposite produced copiously in the aftermath of the Monopoles geomagnetic poles. Following a reversal of the earth's magnetic field (an event observed repeatedly in the which, cosmologists generally big bang with geological record) the two segregated populations of monopoles would migrate through each other. Some would believe, the universe began. meet and annihilate each other, converting their mass into energy, which could be observed in the outflow of heat Up to times as little as 10-35 seconds after at the earth's surface. the big bang, the universe would have been ous. But there are a lot of ideas around, many The contrary view holds that all searches hot enough talmost 1030 degrees Kelvin) to quite bizarre. with ionisation detectors are doomed to generate such particles. Both north and of them are expected to failure because the slow -moving, super - south magnetic monopoles would have been The massive monopoles slowly, at speeds far below the velocity heavy monopoles will cause no ionisation. formed, and a small fraction of them would travel The of a superheavy mono- Another possible means of detection is have recombined, annihilating each other. of light. collision pole and a stationary atomic nucleus would based on the fact that the passage of any Most of the superheavy monopoles would be like a steamroller hitting an ant. A cosmic charged particle through metal is accom- have escaped an early death, however, and ray monopole could lose a huge amount of panied by eddy currents. These eddy there is no reason to think they would not as it ploughed its currents are independent of the particle's have survived to the present. energy to such encounters way through the earth, and it speed and w hether its charge is electrical or Researchers at the European Organisa- ponderously emerge virtually unscathed from magnetic. A spherical metal detector has tion for Nuclear Research 10ERN in Geneva might still other side. been designed but the signal can only be de- decided that the interaction of monopoles the So under these circumstances it is difficult tected above the background noise if the de- with the galactic magnetic field sets a limit to predict what degree of ionisation would be tector is cooled to a few millidegrees above on the ratio of magnetic monopoles to pro- observed in a detector. Whatever happens, absolute zero; a difficult technical require- tons of about one to 1020. Given that abun- that an extremely large detector ment with a large detector. dance, some 200 monopoles per year would it's obvious is required if the experimenter is to observe a One comparatively simple strategy for de- be expected to pass through an area of one monopole event in his lifetime. tecting superheavy monopoles, which does square kilometre. A more conservative esti- One detector which records the light not rely on assumptions about mass, calls for mate, based on a more uniform distribution generated by ionisation and covers many a superconducting coil similar to the one of monopoles in the universe, would result in square kilometres has been developed at the used by Alvarez and his colleagues. a flux of a few monopoles per year per square University of Utah. The device, called the Blas Cabrera claimed to have detected a k i lomete. fly's -eye detector, is an array of photomulti- monopole with a superconducting niobium So for the first time the theory of magnetic directed at the night sky; it re- coil five centimetres in diameter, kept in li- monopoles provides estimates of the ex- plier tubes light given ofTby secondary parti- quid helium at a temperature only 4.2 de- pected mass and flux of magnetic monopoles. gisters the -high-energy grees above absolute zero. At least these estimates, even if they are cles produced by rare ultra interactions in the upper Another plan is to mount a superconduct- rough, provide a fresh field for experi- cosmic ray As the secondary particles ing detector under an iron -ore processing menters to explore. atmosphere. toward the earth they collide plant which heats more than a million tons of One place to look for superheavy mono- shower down nitrogen atoms in the atmosphere, ore per year to a temperature of 1700°C, At poles is in large-scale natural effects. So with to scintillate. However, the this temper'atur'e any magnetic monopoles what was the fate of monopoles in the mate- causing them of a magnetic monopole, even with trapped in the iron would be released, allow- rial which collected together to form the so- passage the most optimistic estimate of its ionisation ing them to fall through the detector. lar system? One could speculate that as the rate, would give rise to less than a ten - The discovery of a magnetic monopole earth condensed the monopoles would have of the light needed to setoff the would rank as one of the finds of the century, sunk toward the centre under the influence thousandth . comparable to the discovery of the positron, of the planet's gravitational and magnetic detector. of such a detector to respond to Diracs other great prediction. If the mono- fields. North monopoles would have collected The ability -induced scintillations is limited by pole was found to be very massive. the case near the south geomagnetic pole and vice particle background illumination from stars, overfly- for some form of grand unified theory of versa. ing and other sources such as beacon elementary particle interactions would be From the geologic record it is known that aircraft lights on distant radio towers. Perhaps a strengthened. the earth's magnetic field has reversed many fly's -eye detector could be installed in a large Even if no magnetic monopoles are found. times. Such a field reversal would cause the salt mine such as those now being physicists, being what they are, will not view two separated populations of monopoles to cave or look for proton decay. the negative evidence as conclusive. migrate toward and then through each used to large -volume detector is the Deep other. During theirjourney some monopoles Another Muon and Neutrino Detector and antimonopoles would be annihilated, Underwater within a liberating the enormous energy embodied in which will be sensitive to events References of ocean about a kilometre on a side. their mass. cube 1. R.A. Carrigan, Jr and W.P. Trower. respond the Cerenkov From the measured heat flow at the This detector will to Superheat?' magnetic monopoles, radiation emitted when a particle moves vol no 4, surface of the earth one can set a rough limit Scientific American. 246; the seawater faster than the speed on the number of monopoles trapped in the through pp 91-99. April 1982. in water. Unfortunately superheavy the core; the number calculated in this way is of light 2. C. Sutton. Hare physicists brand magnetic monopoles would probably move consistent with other experimental limits on elusite magnetic monopole!, New to gi ve ofl'Cerenkov radiation. the abundance of superheavy monopoles. too slowly Scientist. vol 94: no 1304, p 336. May Some oft he largest existing scintillation de- 1982. But how do you find them? tectors are too small by a factor of about 100 3. C. Sutton. Magnetic monopoles Jail to to have a good chance of observing magnetic oblige the physicists. New Scientist. The design of a detector to search for these monopoles if the flux is limited by the vol 97: no 1349. p 721. March 1983. heavy. are particles is. however. not obvi- galactic magnetic field. 14 - July 1983 ETI Sight and Sound NEWS Betamovie here in November y Sony's revolutionary compact colour video cam- era - it packs the standard Beta -format cassette into its own body, resulting in easy handling and increaséd portability - will go on sale in Australia in November. Called the Betamovie, the It records on any standard Australian package will in- Beta cassette, which can be clude the camera, an ac played back immediately on any adaptor and a battery pack, Beta -format video cassette re- and is expected to sell for un- corder. An adaptor is not nec- der $1500. essary. The Betamovie, which measures The currently available Sony 125 x 220 x 357 mm, features a SL-F1E portable video recorder, single -head drum three -fifths which comprises separate cam- the size of a conventional head, a era and cassette pack, will be 13 mm SMF Trinicon pick-up promoted as the 'pro' model of the tube for higher resolution and Sony portable range, offering sensitivity, an F1.2 lens with editing facilities and instant macrofocus and a 6x power zoom, playback. The Betamovie will be and a through -the -lens view- aimed at the 'home movie' finder. market. A single button on the hand- Weighing just 2.48 kg, the Be- grip starts and stops the record- tamovie takes full advantage of er. The rechargeable battery the Beta cassette - it is more pack fits into the handgrip. compact that the rival VHS cas- For further information con- sette - and is only slightly tact Sony Australia, 453-463 larger than a deluxe 8 mm cam- Kent St, Sydney NSW 2000. era. (02)266-0655. Yamaha's commercial power amps and recording mixer Howdey, Partner... have a The four heavy duty two -channel power amplifiers TEAC Australia has released what it calls 'the ultimate nominal both channels driven power output (per channel, personal stereo'-theTEAC Partner, Model PC-7RX. into eight ohms) as follows: PC1002-120 W; PC2002 and The Partner incorporates con- PC2002M-240 W; PC5002M-500 W. tinuous automatic reverse and a The 'M' suffix denotes a pair of The RM804 is a new 8x4 bus noise reduction system toelimin- large peak -reading meters that mixer designed for four and eight ate tape hiss. This has previously display power output in watts track recording. Each channel been a problem with personal or dB. has an electronically balanced stereos, due to the very nature of All models have a typical sep- midline input and an unbalanced headphone listening. aration of better than 80 dB tape input. Available options include the wideband (95 dB at 1 kHz) so the The XLR mic/line inputs have LS -X3, an internally amplified two channels may be used for continuously variable gain trim mini -speaker system and the different programs (or two bands controls which enable the TP-7 AM/FM stereo tuner. of bi-, tri- or quad-amped system). sensitivity to be optimised for Meanwhile, TEAC Australia By sliding a rear panel mono levels from -60 to -20 dB, cover- has been appointed Australian switch, the amplifier outputs can ing most microphones and electric distributor for the Japanese be bridged to deliver significantly instruments as well as many line range of Denon cassette and more power into eight or 16 ohm level sources. open -reel tapes. Denon is recog- loads. Following the mic/line-tape nised as one of Japan's leading Harmonic distortion is typically switch, the signal goes through a m a nu factu rers of magnetic tapes 0.005Ck (20 Hz to 20 kHz, both 3 -band equaliser. and produces one of the largest channels driven) and intermodu- For more information on ranges available. lation distortion is below 0.0154. Yamaha products contact Rose For further information con- Their noise floor is from 110 dB Music Pty Ltd, 17-33 Market tact TEAC Australia, 115 to 120 dB below maximum rated St, Sth Melbourne Vic. 3205. Whiteman St, South Mel- output. Massive side -mounted (03)699-2388. bourne Vic 3205. (03) heatsinks cool by convection. 699-60(X). ETI July 1983 - 15 Sight and Sound NEWS Visionhire defends Videotex Despite the critics'dire predictions for Videotex in Auátralia,Visionhire is confident that thecomputer-based r- two-way information system, which involved telephone - line access to data -storage bases, has a bright future. Visionhire is a member of the "On the other hand, Videotex newly formed Australian Video- found an immensely receptive tex Industry Association which market in the business com- has set, as one of its goals, the munity. From day one it has been dissemination of accurate infor- aimed not as a system for public mation on Videotex, to counter- use but as a system of providing act the confusion arising from information retrieval by the misleading reports. business community. Hitachi digital audio disc player According to David Peers, "That's not to say, however, Visionhire's technical director, Videotex will always remain audio discs that The Hitachi DA -1000 plays those compact digital "Most of the negative viewpoints within the narrow confines of the which have been so much in the news lately. have been almost word-for-word business market. There is abso- Each compact disc has a frequency response of 20 Hz to recitations of the British experi- lutely no doubt that it will one diameter of 120 mm and has a 20 kHz, a dynamic range of more ence." (In Britain, the equivalent day beome commonplace in our playing time (on one side) of than 90 dB and total harmonic Prestel system has had a difficult homes." 60 minutes. distortion of less than 0.03%. The beginning.) Since the disc is read optically wow and flutter is to crystal oscil- through a transparent protective lator precision and the channel layer, dust and scratches have no separation is more than 60 dB.. effect on the sound. Of course, The Hitachi CD player features Zr deep, concentric scratches can pickup forward and reverse, cue, obscure the data to a point where repeat and auto search which is a any brand of CD player will not function that lets you quickly be able to conceal the errors. hear any selection no matter To store information on a com- where it appears on the disc. pact disc the sound is sampled at Program playback allows you to a rate of 44.1 kHz and then each program up to 15 selections for sample is given a 16 -bit code. The playback in any sequence auto- Stereo vadeo from the General code is printed on the disc as a matically. series of reflective pits which are For more information on the General Electric's new Model GE -V-8900 stereo video- read optically by a laser beam DA -1000 contact Hitachi, 153 cassette recorder incorporates two audio channels which and then converted back into Keys Rd, Moorabbin Vic. 3189. allow playback of pre-recorded stereo videocassettes and music. (03)555-8722. taping of simulcasttelevion programmes. The DA -1000 claims to have a The front -loading recorder ure, the system has a clock/timer has a multi -programmable timer memory -hold system with a for pre-setting the recording of back-up time of about 10 min- up toeight programmes from any utes. channel within a 14 -day pro- This is the second General gramme. Electric VCR to go on the It also has a search function Australian market - the first which moves the picture at nine was the economy unit, Model times normal speed, both for- GE -V-6900. ward and reverse. A variable - For additional information speed playback gives double contact Rank Major Ap- speed, slow motion, freeze-frame pliances, 19 Forge St, and frame -advance modes. Blacktown NSW 2148. (02) To prevent the loss of part of a 671-1322. progamme during a power fail - Philap's super VCR Philips has launched a new top -of -the -line model for its Pocket display with amorphous silicon range of VHS-format,front-loading videocassette television sets thin-film transistors. recorders. Sanyo has started Reliability has also been im- Designated the VR901, it has a ing facilities, the VR901 has a production of pocket-size proved, along with contrast, socket at the front cordless remote -control unit of the unit that LCD -based television sets wider viewing angle and response which duplicates the full 14 allows the direct connection of a speed. with 75 mm and 100mm functions of the VCR's main video camera. The 100 mm screen model has control panel: adjustable picture The VR901, which retails at screens. a display size of 60 x 80 mm, and quality; two picture search $1299, allows full stereo sound to Sanyo says it has overcome an overall size of 253 x 30 x 113 speeds in both forward and be played throughexisting stereo major problems with the driving mm. The reception bands in- reverse; a clear freeze-frame systems and is equipped with a systems, while the development clude both UHF and VHF and picture; and a tape -elapsed indi- Dolby noise -reduction system. of a 'stacked liquid -crystal the batteries provide four hours cator which is adjustable for For further information, con- matrix panel' has produced clear of viewing. cassettes from E30 to E240. tact Philips Industries, 15 Blue pictures. The panel combines a No other details have been In addition to the usual record- St, North Sydney NSW 2060. newly developed liquid crystal released. 16 - July 1983 ETI The Ultimate Performance - /.. I I 1 _i _ 1 i 1"`"ez,%. The new Special Performance Series . Components from Pioneer. . 8888 The sum of these components is probably the r ~ti most technologically advanced sound reproduction !` system available from any one of the world's manufacturers. ' --`'t,,_ 120 watts per channel. Dynamic Power A-70 Amplifier. 1 \®® Non -Switching Amplifier, featuring DC - Servo high -gain phono equalizer, Line Straight switch and I.E.D. peak power indicators. F-90 Tuner. Digital Direct Decoder Tuner featuring i. Quartz - PLL Digital Synthesized Tuning, 8FM/8AM station presets, I.F. Bandwidth selector and Record Level Check Switch. CT-90R Cassette Deck. Three head auto reverse record r If there's anything more you'd like and play cassette deck, featuring Pioneer's own Ribbon to know about Pioneer's amazing Sendust heads and the computer aided convenience of Performance Series Components,piease mail Music Search, Blank Search, index Scan, Blank Skip and this coupon to 'Performance Components Reverse, Music Repeat and Real Time Counter; auto B.L.E. Brochure', Pioneer Electronics Australia Pty. Ltd., PL-S70 Turntable. A fully automatic DirectDrive P.O. Box 295, Mordialloc. 3195. Turntable, featuring Quartz-PLL coreiess DC - Servo Hall Motor with Stable Hanging Rotor, low mass straight Name P.G. tone arm with Dynamic Resonance Absorber, and automatic operations of record detection/selection and repeat. Address SG -540 Graphic Equalizer. Seven band graphic equalizer, featuring L.E.D. - lit slide controls, equalizer recording and tape monitor switch. State Postcode I'd like to know more about Pioneer's L Performance Series Components. PIO 0293 O2 PIONEER Product specifications subject to change without notice. Leads the world in sound. Pioneer Electronics Australia Pty. Ltd. lincorp.tn victoria), 178-184 Boundary Rd., Braeside 3195. Telephone: (03) 580 9911. Branches in ail States. Classifieds Sight and Sound NEWS 15 per character Minimum of 32 characters CHARGES: Cash with order only REPAIRS to all home, hobby and COMMODORE 64/VIC-20: small business microcomputer CASSETTE INTERFACE to SAVE/ . -';` systems and peripherals, also all LOAD programs (including . EA & ETI projects. CAE Electronics, Commodore tapes) using your 1/27 Forge St, Blacktown 2148. audio cassette recorder. 545,00 (02 )62 14242. plus 53.00 p&p. Canberra Com- puters & Consultancy, PO Box 382, DIRECT CONNECT MODEM - Dickson, Canberra ACT 2062. Tel: A new high performance micro: (062) 41 3746. processor controlled modem has received Telecom authorisation 16 BIT COLOUR! Texas colour #C83/37/ 1021 capable of 300, 600 computer TI 99/4A! Fantastic colour and 1200 baud with a RS -232-C graphics and sound. Expandable! interface. For more information Heaps of software! Only 5499 (p&p about the 'MICRO -MODEM' write 59). Orders: Software Connection. Digital age speaker systems to the manufacturer: Woomera Box 375. Pymble NSW 2073 of Electronics P/L, P.O. Box 32, B'card Hotline (02) 30 1839. Pioneer's three new speaker systems feature two Camberwell Vic. 3124. technologies developed by Pioneer to take maximum COMPUTER Clinic repairs and FERGUSON TRANSFORMERS advantage of digital recordings. services Sorcerer. Pet, Apple, 20FF. 240/ 100V, 10/23A at 5280 The cone material is polymer extremely low mass diaphragm System 80, Super 80, Tandy and each as new, used for computer graphite which is as stiff as metal for better transient response others. (07) 269 8573. P.O. Box 68, power supply. Contact R. Bailie on and has the excellent damping together with individual controls Aspley, Qld. 597 1911. qualities of paper, yet generates for adjustment of middle and significantly less distortion than high frequencies. either. The 5710 bookshelf system has Pioneer has also developed a a large 30 cm woofer and 10 cm range of ribbon tweeters which midrange with an aluminium have eliminated voice coils com- ribbon tweeter which gives a pletely because the entire direct - wide dynamic range. driven diaphragm surface acts as The S-510 bookshelf system the voice coil. It is claimed that has a 25 cm woofer and 4.5 cm PRICE this results in a wider frequency midrange with an aluminium range, better transient character- tweeter to handle frequencies up istics, lower distortion and far to 50 kHz. wider dynamic range than any Retail pricing of the systems competing tweeter designs cur- will range from approximately rently available. $650 per pair for the S-910 down The S-910 is Pioneer's top to approx. $350 for the S-510 type. bookshelf style speaker system For further information contact and contains a large 30 cm woofer Pioneer Electronics Aust. Pty and a 10 cm midrange speaker. Ltd, 178 Boundary Rd, Brae- The beryllium ribbon has an side Vic. 3195. (03)580-9911. AUSTRALIAN S i MA n New Dynavector tonearm and cartridge Noise Suppression Transformers are half Concept Audio now has the Dynavector DV.501 tonearm the price of constant voltage transformers which is a refined version of the DV.505 tonearm. Ideal for computer installations in cities It features a dual pivot system not require a step up device and where mains spikes are a problem and electromagnetic damping. It is designed specifically for use in Ratings to 3600VA also incorporates a cueing device. moderate priced hi-fi systems. No installation costs The complete package has a The recommended retail price recommended TALK TO FERGUSON - THE AUSTRALIAN COMPANY retail price of $498 of the DV.10X.3 is $148 and it and will fit onto most standard is also available pre-packaged WITH NEARLY 50 YEARS EXPERIENCE OF MANUFACTURING sized turntables. and mounted on a high IN AUSTRALIA FOR AUSTRALIAN CONDITIONS quality To complement the DV.501, a Ferguson Transformers Pty. Ltd. magnesium alloy headshell at Dynavector has 331 High Street, CHATS WOOD 2067 Tel: (02) 407 0261 introduced the price of $175 complete. Telex: AA25728. Melbourne (03) 328 2843 DV.10X.3 cartridge which is Dynavector products can be lower in mass than its pre- obtained from Concept Audio decessor, the DV.10X.2. It weighs Pty Ltd, 17/98 Old Pittwater three grams and the output Rd, Brookvale NSW 2100. _FER6USON voltage has been increased to (02)938-3700. 2.6 mV. The new DV.10X.3 does 18 - July 1983 ETI SONY, THE ONE AND ONLY The Sony CDP101 The magic of digital audio becomes a magnificent reality. Digital Audio is a revolution. The greatest automatic music sensor dual function digital advance in home music reproduction since the readout of playtime audible fast forward and gramophone reverse 10 function wireless remote control. record. As you'd Compact Discs Last Forever expect, Sony is the Just 12 cms in diameter, the Compact Disc leader of this plays up to 60 minutes of music. It's protected from revolution with its scratches, dust and finger prints a magnificent by plastic coating; and because the pick-up is a laser beam, CDP-101 player. deterioration is non-existent. Reproduction remains that offers you perfect virtually forever. original studio Hundreds of titles will be available with many master quality at more to follow from major home. companies such as CBS. For the CDP-101 Specifications technically minded, the specifications Frequency Range 5Hz-20kHz ± 0.5dB read more Dynamic Range more than 90dB convincingly than S/N more than 90dB any superlatives Channel Separation flat frequency more than 90d B (at 1kHz) response over the entire audible range dynamic Harmonic Distortion less than 0.004% (at 1kHz) range and signal to noise ratio over 90dB perfect Wow and Flutter immeasurable channel separation immeasurable wow and flutter negligible distortion. Sony's CDP-101 uses an optical laser pick-up (incorporating three micro processors), it is easier to SONY use than a conventional -- turntable and connects easily to your existing T system. MG-_; o0 Other features mmo. include fully W0.7. automatic linear skate _~3. front disc loading Contact Sony for the name of your nearest dealer. Sydney (02) 2660655, Adelaide and N.T. (08) 2122877, Brisbane (07) 446554, Perth (09) 3238686, Melbourne (03) 4193133, Launceston (003) 443078, Wollongong (042) 715777. AU00378 o JañiO-CBR 1703 loudspeakers Louis Challis o ... "offer a performance bordering on the superlative.'' New on the local scene, these four-way Danish speakers are well matched to the compact disc players. Well designed, they are able to handle peak power levels of 600 W.with low distortion. MOST OF OUR READERS will probably re- make this speaker stand out in the An overall view member 1983 as the year of the compact disc, marketplace. affectionately known as 'CD' by the trade. A four-way speaker system is not usually After you remove the speaker grill the most However, I suspect the trade, over- my 'cup of tea' because it makes the testing unusual feature of the speaker system that whelmed with problems, some of which are more complicated; however, I realise that catches your eye is the method of loading the technical but generally financial, will not this system does have obvious attributes. low frequency driver. This makes use of a remember 1983 with so much affection. It was purely coincidental that at the time 'centre bass reflex' (abbreviated to CBR) One of the most interesting technical prob- of reviewing the Jamo speaker system I had system in which the woofer is inserted in the lems facing the high fidelity industry is the the good fortune to have three different CD middle of its own circular, annular loading obviously wide gap between the technical players in my house. It seemed that these port. performance of the new CD players and that two separate sets of circumstances were The woofer is supported on four rectangu- otléred by the 'average' loudspeaker of the auspicious, for many people at this moment lar rubber isolating mounts which are appa- type that you might buy in your local hi-fi are considering whether or not their existing rently intended to vibrationally decouple the shop. speaker systems are suitable for use with CD driver from the cabinet and from the loading CD players, w ith dynamic ranges of 90 dB players. port structure. The lack of resilience of these and frequency responses that are flat from It seems appropriate for me to look briefly a speaker 10 Hz to 20 kHz, really need loudspeakers to at the specific attributes that SOUND be better than they have ever been before if system should possess if it is to be suitable for LEVEL KIM they are to do credit to the new medium. So it listening to a CD player system. Obviously. 50 is not surprising that most of the major one of the first requirements is that its fre- 45 speaker manufacturers or their importers quency response should ideally extend from 40 are concerned that their cheaper speaker en- 25 Hz or at worst 40 Hz through to 16 kHz 35 closures might not be suitable for the new and be as smooth as possible. demanding task. This frequency response should be 30 Until these Jamo speakers turned up for supplemented by low distortion at high sig- 25 review I must admit I had never heard of the nal levels, low colouration from the drivers 20 system came and the cabinet, low intermodulation distor- firm. The speaker that out of 15 the box was sufficiently unusual in its ap- tion, a good transient decay response with pearance to provoke a lot of comment in our minimal resonance, broad non -directional to office. output in the horizontal plane and the ability 5 The 'CBR' concept, which stands for to handle transient signals with peak powers but which I would de- of hundreds of watts. Centre Bass Reflex, FREOUENcrluur scribe as the Circumferential Bass Reflex, So it was with these salient criteria in obviously has its merits. If this concept is mind that I proceeded to evaluate the Jamo Every picture tells a story. The decay response half as good as it*seems to be. it could well CBR 1703 loudspeaker system. spectra for the Jamo CBR 1703 loudspeakers. 20 - July 1983 ETI SOUND REVIEW JAMO CBR 1703 LOUDSPEAKERS Tone burst response of the Jamo CBR 1703 loud- speaker system. For 90 dB steady state sound pres- level at two metres on axis. Dimensions: 425 mm wide x 365 mm deep x sure trace is electrical input. Lower trace is the 810 mm high Upper loudspeaker output. Weight: 31 kg Price: Rrp $1695 per pair, including PERFORMANCE pedestals MEASURED OF: Manufactured: In Denmark by Jamo-li-Fi JAMO Model 1703 Distributor: Scan Audio, P.O. Bdk 741, 111141111111111111111111 Dandenong Vic. 3 /75. !'!1'111111111111 (03)793-5670. FREQUENCY RESPONSE: 35Hz - 18kHz four rubber mounts leaves one with the im- mediate impression that they can only be CROSSOVER FREQUENCIES: T really effective at high frequencies and y therefore they must be relatively ineffectual 280Hz/ 1400 Hz/3500 Hz at low frequencies. The woofer speaker is a 325 mm diameter unit with a large rolled plastic edge. Behind SENSITIVITY: fl the main driver is a reasonably large (for 90dB average at 2m) Output at 100 Hz (20 ms/div). ceramic magnet assembly. The woofer edge frame is designed to create the inner element 5.6 VRMS - 3.9 Watts (nominal into 8t ) of the C)3R system, while the outer table element on which it is supported by the rub- ber blocks forms the other element of the HARMONIC DISTORTION: CBR system. (for 96dB at 1m) is 173 mm driver The low mid -range unit a 100Hz ]kHz 6.3kHz with plastic roll edge support, the mid -range unit is a 50 mm domed tweeter and the twee- 2nd -43.3 -47.4 -55.2 db ter is a 25 mm domed unit. 3rd -45.6 -44.9 dB The distribution of these individual low mid -range, mid -range and tweeter units on 4th -62.2 -72.6 dB the top of the cabinet is asymmetrical with 5th -66.0 -67.6 dB an L-shaped configuration. This must affect THD 0.76% 0.71% 0.17% the uniformity of the sound field in the mid- range region and detract from the direc- Output at 1 kHz (2 ms/div). tional attributes, rather than optimise the INPUT IMPEDANCE: sound field generated by the speaker. 100Hz 5.6 ohms Thin foam plastic has been inserted around the mid -range and twéeter units to ]kHz 9.5 ohms Fil minimise the diffraction effects at the front 6.3kHz 8.2 ohms of the loudspeaker. However, the foam that has been chosen has apparently been Minimum at 90Hz 5.4 ohms selected on the basis of its durability rather than its acoustical absorption. The concept of forming the front of the Absolute copyright in this review and accompany- speaker enclosure from a plastic moulding is ing measurements is owned by Electronics Today delightfully simple as it saves all the International. Under no circumstances may any expense of machining wood and all the other review or part thereof be reprinted or Incorporated required in the in any reprint or used in any advertising or milling operations that are promotion without the express written agreement construction of conventional wooden enclo- of the Managing Editor. sures. Output at 6.3 kHz (0.5 ms/div). e Ottw . .M.. Louis Challa - Louis A Challis I I w-` `" A n- °'~' ...eu.M, Pb u. 0 bMn.u,weie R..te 50 de R«IA* C1-1 ERA, l.M Fp sR»a IBZ .. e,00+M. R.y SSA ull R.as- Q...5 ER -e. N, W 90e.4 -11i 1111111111111111111111111111111111111111111 INPUT rr111i1 FREQUENCY IMPEDANCE ri re 11111 RESPONSE OP OF ®I11111NNINNI11111111111E® 16 JANO LOUDSPEAI(EII JAMO LOUDSPEAXE MODEL CBR1T03 MODEL CBR1T03 " 111111 IIMI11I11111M11111uN11111111 111111111aEN11111Bh11111® MEASURED AT 2M CONTROLSCTROLS I.AT 11111r,J1i:!',!1!'!IIIAIIP,V EB O: TWEETER IilllHHNIIlI1 AXIS SNOWING 1.1:'Hi!111II NI IIIIrrIN1®1 111111111111111111N111111®111111M EFFECT OF MID AND H.P. ®1NIII11rNI1NIf1BI1N1® 111E1111111111111111111111111111111111111111 CONTROLS (MOM MIN(MUM) NINmumIIHIzorsom11em W1111111111111a118111111i1LNIN. 12 11111111111E111111111111111111111111111111111 Dote, 20-2-03 D.t., 20_2-83 EZ11111111911111111111111 EMIZZENCLIChral10000 ]COPO 1000 3000 e Ho 10, 100 1000 2000 1000 111000 0 00 10 100 200 100 2000 1,012/2112 Yampa F..e...Mq Sure I lam lo.O 11012/2112 M. Pea Frog,.r SR. 0 1 z... C..M ETI July 1983 - 21 It also means that the complications in The rear of the cabinet contains a terminal providing mounting holes, mounting connection box with two colour -coded, large, systems, dimensions of those systems and spring -loaded terminals to accept bare the fabrication of the other complex parts of speaker wires which may be up to 2.5 mm in the system are minimised. It is all economi- diameter. cally fabricated in one simple operation. Even the mounting holes for the fancy cloth - Objective testing covered front of the cabinet are moulded into the face structure and may then be forgotten. We placed one of the Jamo speakers in our What may have been overlooked is the re- anechoic room and proceeded to evaluate its sonance and damping characteristics that a objective performance. The first data we pro- plastic system provides when compared to a duced was the impedance curve which pro- well -braced timber system. vides an assessment of the CBR system. This The whole front of the speaker cabinet is displayed two significant resonances; the moulded as a complete unit. This provides for first one is due to the main venting port of the all the mounting requirements of the indi- CBR resonance which peaks at 12 Hz. The vidual speakers as well as incorporating the second resonance is the main speaker reso- treble and mid -range attenuators on the top nance which occurs at 51 Hz with a peak lip of the cabinet and overload indicator impedance of21 ohms. lights on the front edge of the cabinet. The minimum impedance measured is ap- The front clip -on panel which supports the proximately six ohms at 90 Hz. The rest of black speaker cloth is also a plastic moulding the impedance curve from 100 Hz to 20 kHz and it seems that one of Jamo's strongest is relatively smooth and consequently safe points is their moulding technology and the for virtually all amplifiers with which it is extent to which they are prepared to utilise likely to be used. their plastic mouldings and automated pro- The frequency response of the Jamo 1703, cesses to reduce the manufacturing costs. when measured on axis and without a reflec- tially different from the manufacturer's The cabinet structure is unusual as it fea- tive plane underneath the speaker, is not claims. The lowest crossover between the tures a contoured front panel. The full particularly smooth and lies within a range bass driver and the low mid -range is not easy significance of this does not become apparent of ±6 dB from 38 Hz to 20 kHz. Obviously to pick, even with a microphone close to the until you see the supporting steel pedestals with the speaker mounted on its pedestal speaker, and I gained the impression that on which each speaker is to be floor - above a reflective plane, the bottom end the woofer was not delivering its fair share of mounted, or until you examine the installa- response would receive a significant lift as a the total output. tion instructions that show how the unit may result of the floor reflection. This does com- The mid -range attenuator, which is one of optionally be mounted upon the wall. pensate for the drooping low frequency the 'push to activate' type, provides useful The pedestals unquestionably enhance the response that is visible in the level re- adjustment between 1500 Hz and 6 kHz, appearance of the speakers as well as being cording. which is a maximum of -7 dB between functional. Each pedestal is a very strong, The frequency response exhibits a far 1800 Hz and 3 kHz. The treble attenuator, two-piece, 4 mm thick steel unit with greater number of peaks and bumps than I which is located next to the mid -range unit, interlocking elements. These provide a back- would have expected, particularly in the provides effective attenuation from 2 kHz to rest which restrains the back of the speaker. 350-500 Hz region and again between 20 kHz with a maximum of -14 dB between On the top of the pedestal are four self- 2000 Hz and 7000 Hz. There is also a sharp 7 kHz and 14 kHz. The values and gradua- adhesive pads which reduce the likelihood of rise in the response between 8 kHz and tion of attenuation are sensible and it is clear the speaker system slipping off the top of the 16 kHz. These peak responses are measur- that the designers have put a lot of thought stand. able and, as we discovered later, audible and into both the ergonomic and electronic de- With typical Danish ingenuity the pedes- give the speaker a degree of frequency col- sign of the attenuators. tal is very simply manufactured to provide ouration which affects the audible response The overload indicator lights did not regis- strong and resilient support for the speaker on both classical and pop Music programme ter at all during our testing and I suspect as well as providing a small degree of vibra- content. I pondered the non -linearity and that I just did not push out enough power to tion decoupling for low frequency energy be- suspect that the individual components are activate them. ing fed through to the floor. This is evident as not closely monitored for uniformity of The speakers are quite efficient, requiring the low frequency performance is substan- performance. less than four watts to produce 90 dB at two tially improved in the critical 25 Hz to 40 Hz The speaker crossovers occur at 250 Hz, metres. This means that with a 100 W stereo region. 1400 Hz and 3500 Hz, which are substan- amplifier peak levels of greater than 110 dB .,m .p. Louis A Chalks t Louis A Challis &'-a Pry IX zM A,Qr.m 8.0e1 R0ur d8 Se ae RMfiw QA*`i lew. L. P.w w w. SOa 1i2 P 1000 u_ w,.. PHASE RESPONSE FREQUENCY OFSEOF RESPONSE or JAM IQUOSPEAXER JARO L0UDS PE AXE MODEL CRP 1702 MODEL C0R1F03 MEASURED AT 28 - YEASUR.D AT ON TWEETER IM ON TWEETER AXIS AXIS WITH 000180LS SET AT FLAT WITS CCWTRO1$ SET AT FIAT .P 1 Date: 20-2-83 1 0.1e1 00 -I -8I -180v f I 1 A S S 151132 IL 15 % FO 15 12 100 100 SDO 100C IDDO 5000 10000 20000 NO RR P.a.,5..«.u, 1 EvoLeni 11617/2111 22 - July 1983 ETI SOUND REVIEW are possible in a normal moderately rever- berant living room. FRONTPANEL The phase response of the Jamo 1703 is OUTER TUBE extremely smooth and it is clear that, even arti though the unit contains four RUBBER SUSPENSION separate ;~11 BASREFLEXPORT OM, drivers and their associated crossovers, the designers have achieved a commendable re- INNER TUBE sult in precisely positioning the drivers and in designing matching crossover networks that appear to work well. The distortion levels are particularly low, BAS REFLEX SPACE being well under 11 at 100 Hz and 1 kHz RUBBER SUSPENSION and less than 0.24 at 6.3 kHz. The low dis- tortion levels are a primary feature of these speakers and the distortion levels do not really become significant until the power level approaches 100 W (i.e: 107 dB at two metres on axis). I was not surprised to find that both the tone burst testing and the decay response INNER TUBE spectra produced excellent results. Only moderate levels of decay resonance were ap- RUBBER SUSPENSION 4111I11 BASREFLEXPORT I110/ parent at about 5 kHz and even this was well down compared with the peak level. signal OUTER TUBE This part of the testing was particularly pleasing as it augured well for the subjective FRONTPANEL testing that followed. Fundamental construction of the Centre Bass Reflex system. Subjective testing tionably different from what it should be. By again rewarded with the magic of crystal With a choice of three CD players, more than contrast, on organ music the speakers were clear digital recordings free of clicks, pops or a dozen compact discs and many excellent absolutely outstanding. background noise. The Jamos were really in conventional records, I had what I I can only played Virgil Fox's `The Digital Fox' IU1- their element and I was suitably impressed call an exciting time. tragroove UG9001) and was amazed how that these speakers are the first of a new The music on the compact discs was ex- well these speakers coped with the record. generation of speakers that are well suited to hilarating and the performance of the speak- The low frequencies were full-bodied w ith no the CD generation. ers was generally extremely good. The first signs of frequency doubling and remarkably The Jamo CBR 1703s are an exciting thing was that apparent was the ability of free of distortion, while the mids and highs speaker system which is generally well de- the Jamos handle an to instantaneous peak were rich and vibrant. The speakers repro- signed, well executed and which offers a power up to 600 watts per speaker without duced the organ almost as well as any speak- performance bordering on the superlative. complaint and with remarkably low distor- ers I have heard, and they handled peak They are well suited for listening to both tion. At these power levels the sound pres- levels of over 400 W without complaint. The classical and rock music and are not afraid to sure level in my living room was over 114 dB overload lights didn't come on and I was handle power levels which would quickly and my family was starting to complain. quite impressed. destroy lesser speakers. The was sound remarkably clean but by I played an excellent Mobile Fidelity re- The only factor which detracts liom an comparing the outputs of selected tracks cord, Earl Klugh's'Finger Painting' IMFSL almost perfect testing and subjective assess- against my reference speakers it was clear 1-0251, and was rewarded with rich trans- ment is the variability of the mid -band fre- that the mid -range balance was not really ients and exciting percussion. However, the quency response and the consequent fre- perfect and that speech and singing had response was coloured and the 'sound of the quency colouration. quite discernible colouration. This was read- speakers' was superimposed on the sound of Jamo would do well to spend a little more ily observable on Classical Guitar IAlbeniz the music. The staccatos of the Earl Klugh time and effort in matching their individual Granada - track nine on the Sony CD disc were not quite as clean as they are on the drivers if they would like a five-star rating YEDS4; Demonstration disc, Volume 11. The monitors and I was a trifle less impressed. instead of the excellent four stars that they sound was not at all poor but was unques- I returned to the CD players and was once won for this review. bee, { aMw Louis A. Challis .- eN a,a, eve, a ape 1 Asear RM W Op Louis A. C7WIis - J I. °:"*L' ro 1 A,ec bbne...,, b.7 ES Oh. 2A« t Le+w L.w -IL a I1,Yw.N.. °' w ee . ,. .e,..,.e..,.. .M1. Me RaMM. _ To QMa4 La+Lw E. L0 w S. So..' IaL.w. "1r{ r JAMO LOUDSPEAKER MODEL CRR1702 3510 LOUDSPEAKER MII1®amllMia1MII1®MMMnII®MMnI1O MODEL CAR1703 MEASURED AT 2M ON TSETER EMII111=111.11111111111111111 MEASURED AT 2M ON TWEETER AXIS SHOOING EFFECT Or AXIS SNOWING ¡. EFFECT Or MID CONTROL NIGH CONTROL AT AT MINIMUM 11111.%1211!1tMInI1nM11f2u;lM1 Ifi®l1111r1MIn111I111IIM1111 MINIMUM F WMMI111M111IlIMa1IMM r Date, 20-2-83 II®1III1lINIIiIIN, ii MM1M111lliMOMS1nIIMi Data. 20-2-82 ,MIIIlE1M11111Il1M1inIIMi - , 90 SO 100 200 e00 2111 2rD S000 'WOO 20 A. SO IOC 700 100 1000 2000 1000 '0000 AM.,a frequency Sc.. by Iwo L... 1,1,2,21.2 A.np, F....t, ec.M e, I 2we L. 11117,21.21 ETI July 1983 - 23 SOME COMPUTERS ARE BETTER THAN OT COMPUTER COMPARISON CHART TANDY -' COr1100018 S/RTIAYIDIO (0111606018 64 AIMI a MI5 ATARI 100 ac 70 TRS-80 1V-718 8299 1649 BASE PRICE 8499 82100 81100 114399 COMPUTING POWER FEATURES 12K 10K 20K 20K 8K ROM 32K BUILT-IN 96K N/A 42K N/A N/A 14K EXPANDABLE TO YES COST NO NO NO MICROSOFT BASIC YES ADDITIONAL BUILT-IN EXTENDED 32K' 48K 16K 64K 5K 4K BUILT-IN RAM 64K 414K N/A 32K 32K EXPANDABLE TO 144K KEYBOARD FEATURES 66 66 53 NUMBER OF KEYS 71 51 61 N/A 4 8 8 N/A USER DEFINE FUNCTIONS 10 NO NO YES NO NO NO SPECIAL WORD PROCESSING YES YES YES NO YES YES GENERATED GRAPHICS (FROM KEYBOARD) YES YES UPPER ONLY UPPER/LOWER CASE YES UPPER ONLY YES GAME/AUDIO FEATURES YES NO NO NO YES NO NO SEPARATE CARTRIDGE SLOTS NO NO NO YES JOYSTICK YES 8 BUILT-IN 15 16 16 16 128 192 s 256 COLORS 320 a 200 196 a 184 256 n 192 280 n 160 320 a 192 RESOLUTION (PIXELS) 8 N/A 32 N/A 4 SPRITES 3 3 I 3 I 4 SOUND CHANNELS 9 9 3 8 4 4 NO OCTAVES PER CHANNEL NO NO YES `.ES A.DS.R ENVELOPE YES PERIPHERAL SPECIFICATIONS I 2 CHANNEL I CHANNEL 2 CHANNEL I CHANNEL I CHANNEL CHANNEL CASSETTE YES NO YES NO NO NO AUDIO IO NO NO NO NO NO BUILT-IN MIC YES 256K 143K 96K 170K í90K 156K DISK DRIVE CAPACITY NO NO NO NO NO (LOW PROFILE) YES CP/M COMPATIBILITY (80 column programs) YES NO NO NO' NO NO CP/M 2.2 NO NO NO CP/M 30 YES NO NO modified 40 or 80 column CPJM Microsoft is a registered trademark of MicroSofl Corporation 158 user a0dresS abre Plus 158 graphic suDDon - Apple II can accept is a trademark of Digital Research, Inc 1788 user addresSdole plus '641 graphic suopon " Commodore 64 accepts 40 column CP/M CP/M OURS IS MUCH BETTER When you start comparing Spectravideo's SV-318 to other SPECTRAVIDEO SV318 personal computers, you'll find there really is no comparison. The SV-318 is the only logical choice, because it does more than some computers costing 4 times as much. And its abili- ties simply embarrass other computers in this price range. _ The SV-318 isn't just more capable. It's much sy o4o®e 4raae 4y more capable. No other computer at even twice the price oop p v - near íts 32K ROM expandable to 96K. Or to its 32K 4sizscr0 p comes p©ap Gi RAM expandable to 144K. And no other computer has a 0 built-in joystick/cursor control-an immeasurably useful 4dÓ feature when it comes to playing your favorite video game. Further, the SV-318 has, as its resident "language" Extended Microsoft Basic, the industry standard. It even has built-in CP/M (standard 80 -column program), so you con immediately utilize over 10,000 existing software programs. The SV-318 isn't just more expandable. It's FOR UNDER $500 much more expandable. Unlike many other so-called with the optional SV-105 Graphic Tablet you con draw computer systems, all our important peripherals are avail- pictures, graphs, charts and other visual images on your TV able at once. That means you can get almost full usage out screen. Considering what you get for what little you pay. the of your SV-318 from the day you buy it. With the Super SV-318 is once again the only logical choice. Expander, Data Cassette, Floppy Disk Drive, Dot Matrix Whether you're investing in your first computer, or are Printer, Graphic Tablet and SV-800 Series Expansion already well versed in today's most important machine. do. Or Cartridges, there's almost no end to the work you can you'll find that the SV-318 is the only logical choice for you. to the fun you can have. The SV-318 is well designed to inter- face with new options as they become available, too. All this adds up to a computer you'll grow into, not out of SQECTRFII//DEO The SV-318 is not only eminently afford- able, it's the first real bargain of the computer age! Besides business application, home budgeting, word processing, SV318 programming and self -teaching, the SV-318 is the best enter- PERSONAL COMPUTER tainment value in town. Not only can you use it with your TV VIDEOACTIV ELECTRONICS or color monitor to play hundreds of different video games, 70 St Kilda Road. St Kilda. VIC 3I112. Phony: (03) 537 2(0I COMPUTtild T T Spectravideo SV 318 personal computer The Melbourne -based firm, Videoactive, the Au- stralian agent for Spectravideo video games (in- cluding Planet Patrol, Master Builder and Quick - shot) has just released the Spectravideo SV 318 personal computer in Australia. Spectravideo is an American - based electronics company with an affiliation with Bond - well, a large firm located in Hong Kong. Combining the research and development facilities of the two companies has provided the tech- nological and manufacturing CiÓitpacfO w capabilities to produce the 419414100404211W24.4.4114, SV 318 personal computer. vvV The SV 318 computer features, ó, as standard, 32K RAM; 16K is GQ44 for graphics and 16K is user ad- íti dressable memory. Memory ex- ó pansion can be accommodated up to a total of 144K RAM. The 32K ROM is expandable to 96K with a custom extended Microsoft BASIC interpreter built in. The computer is compactly and stylishly constructed in a console unit with keyboard and TV mod- ulator. The keyboard unit can be linked up with the full range of peripheral options or user de- clock, CP/M compatibility, com- word processor keys. will follow later year. vices through the SV 601 Super this bined cursor/joystick control, With these features and priced More details on the SV 318 are Expander or adaptor to suit all easy loading cartridge slot, at $499 requirements. Videoactive claim that available from Videoactive arcade quality graphics and the SV 318 offers exceptional Electronics, 70 St Kilda Rd, St Other features include a Z80A sound, a seventy -one -key, multi- value. microprocessor with Kilda Vic. 3182. (03)537-2000. 36 MHz function keyboard and built-in The SV 328 personal computer Buggy brings computers to life A robotic vehicle, the BBC Buggy, has been designed to provide children and adults with a stimulating and versatile introduction to the world of computer -control technology. Developed for use with the dimensions and transferring BBC microcomputer, the 127 them to the screen and a sun - mm square vehicle has three seeker program (which enables it wheels driven by two precision to seek out light sources among a stepped motors and is equipped maze of objects). It can also with detectors to feel objects and compose music, reading the seek out light sources, together information from a series of bar- with an infra -red transceiver to codes. read bar codes. Though primarily developed A series of 13 programs are for the BBC microcomputer, the supplied which explore import- manufacturer, Economatics, ant aspects of microcomputer plans to include an interface with f technology. These include a the vehicle so that ít can be used memory function, line follower, with other microcomputers. route planner (in which the For more details contact buggy follows a picture of the Economatics,4 Orgreave Cres- route on the computer screen), cent, Dore House Industrial programs for exploring objects or Estate, Handsworth, Sheffield, a given territory, working out the United Kingdom. ETI July 1983 - 25 THIS ISTHEC ONLY S69Á norm VW 06112 c3 00'rV,B Inv OISS on. CO FOa 1410000 2 COOOO ` Iw ndr de ole 1R w w w1 die ! y1.1 AIAAAilA A1A W MIYuAa AAA PR138 RA A AI AI A A e vW OM, Oft Oft AAAAl,> usiawsn A á b r Cm.veve elf AAA AAAAA n,M 1. foT.L1110 n fo anew rt M bm uP 0 foa ,am Cfo1 J111VP OM W ro[,Ws mating ~am at awn e cw... usdul forme áv(1W ard IN.... la .., .. A .TV»orOawr chralOR.or 0 l I J Íi o M 6 r ' .r r v 41 BMS/CC3OL THE COMMODORE 64 COULD B MICRO COMPUT I TRYS OUTSTANDING N DUCT INTRODUCTION SINCE THE BIRTH OF THIS UIDU RY." -ShfARS(bV/A'vF/CANEX.HESS They're speaking to a group as interested as THE FUN SIDE OF anyone POWER else in the future of computers: the people The Commodore who buy 64 can become very playful at stock in the companies that make a moment's notice. computers. You can use Commodore's plug-in game If, on the other hand, you're a person whose cartridges or invent your livelihood own diversions. All will be depends on a personal computer - or enhanced by brilliant video whose leisure time revolves quality and high around one - what resolution graphics (320 x 200 pixels, follows should impress you 16 available even more than it colors, 3D Sprite graphics), plus impresses investors. outstanding sound. The 64's built-in music synthesizer has a MIGHT MAKES RIGHT. programmable ADSR (attack, decay, sustain, release) The value of a computer is determined by what envelope, 3 voices (each with a 9 -octave range) and it can do. What it can do is largely determined by 4 waveforms. All of which you can hear through your its memory. audio system and see in full color as you compose or The Commodore 64's basic RAM is 64K. This play back. amount of power is unusual enough in a micro at NOW'S YOUR CHANCE any price. If you've been waiting for the "computer At $699, it is astonishing. revolution," consider it as having arrived. Compared, with the Apple 11+1 for instance, Through its 25 years of existence, Commodore the Commodore, 64TM' offers 33% more power at has been committed to delivering better products considerably less than 50% of the cost. at lower prices. Compared with anything less, it's even more Today, the company's vertical integration has impressive. resulted in the Commodore 64's price performance And it can effectively double - your computer breakthrough heralded by Shearson/American equipped work force. Express. PILE ON THE PERIPHERALS Visit a Commodore Computer dealer and Because the basic cost of the 64 is so low, you discover the 64 soon. can afford more peripherals for it. Like disk drives, It will expand your mind without deflating printers or even printer -plotters. your wallet. This means you can own the 64, disk drive CPU. Is a regsfg,etl,radgnark Of ogAU Reseerch. Inc and printer for a little more than an Apple 11+ I I computer alone. 1 Commodore Business Machines Pty. Ltd. HARD FACTS ABOUT SOFTWARE 5 Orion Road, Lane Cove NSW. 2066. (02) 427 4888. I The Commodore 64 will have a broad range of Please send me more information on the Commodore 64 na custom software packages including an electronic 1 Name spreadsheet; business graphics (including printout); I Address a user -definable diary/calendar; word processor; p mailing lists, and more. I I With BASIC as its primary language, it is also Postcode PET BASIC compatible. Phone The Commodore 64 will also be programmable BF in USCD PASCAL, PILOT and LOGO. COMMODORE BUSINESS MACHINES PTY. LTD. And, with the added CP/M© option, you 5 Orion Road, Lane Cove NSW. 2066. (02) 427 4888. will have access to hundreds of exciting software packages. Cr commodore COMPUTER ETI July 1983 - 27 Printout MicroBee games moves around the screen picking Dictionary up urgently needed supplies. software Supertank is pursued by a program homing rocket, Bingle. However, is a recently has a defence. Mine has signed M.B. Software Supertank Software Source software house a mine, can be placed and with Oasis Womb established Drop, an agreement in high quality exploded on command. Bingle is California, for specialising Systems, software for the MicroBee. destroyed if it is passing over the exclusive distribution of time of detonation. chase mine at the powerful new dictionary Mine Drop is an exciting Mine Drop is available on the 16K program, 'The Word Plus'. game for the standard cassette for $12.95 from M.B. MicroBee. The prow am is written 248 Rd, Source will be pro- Software, Brunswick Software in machine code and is fully Vic. (03)380-9805 viding full technical support for Brunswick interactive. The operator controls and from MicroBee outlets. the package which is something the movement of Supertank as it new to those who have used a conventional 'spelling checker' Pineapples are not package. The Word Plus ís a series of Apples computer, has been enjoined spelling check tools from copying or selling any of integrated software which perform a wide range of The Word Plus is compatible Apple Computer has been Apple's copyrighted word - computer's spelling check and word analysis with nearly all CP/M awarded a preliminary programs ín the including the ability processors and text editors. against a Los memory circuits or diskettes. functions, contact injunction the Autostart to find incorrectly spelt words in For further information distributor of one This includes Software Source, 344-348 Angeles ROM, Applesoft, DOS 3.3 and context and to suggest similar of the copies of the Apple II carry out Oxford St, Bondi Junction Integer BASIC programs. words and to actually personal computer being the spelling correction. NSW 2022. (02)389-6388. In Australia steps are being sold in the US. taken to ensure that further AED Formula International, dis- sales of bogus Apple computers AED Universe's Super- tributor of the 'Pineapple' are prevented. Melbourne computer II features a choice of Elston Micro has been 16 -bit single- or multi- eight- or .BDS appointed as Melbourne user operating systems, and has ,.. the Australian - S100 buss compatibility. 11 II dealer for full L " details, contact 1 C . designed and For further I i] k '( , . 1 1 IIZ a 1 19 1. G Elston Micro, 53 Waverley Rd, '1, '1. II ' manufactured AED NfG East Malvern Vic 3145. (03) NI- Universe range of 1 lit IJ IL I I U' + ' t .117.11I4 Y . ;1`' Il `l . . r ! 1 Informntlon Technology Week Ih / °f ! 1 , 1 l g I d L Information Technology Week, an annual national event '141 4410 iA1r.-. 1 1 1 1 IFY I 1 ( 1 1 I 'I 1{i 1 'I I I I I. heightening community awareness and i " 41 ji aimed at . technolog ies, is being held in :` understanding of information 1 'K , 1.1). i j I l' I Wales from August 7-13. New South ó ¡' { ' _ libraries. As part of the activities Syd- la.Iq` s, llrtr tr:. If,.l l lkltl'I'r ,I'ila 'i.' I-Ill' organisa- ,.,, >11.( I ney's Power House Museum Other participating , f"1'. 1!' ( ( z 1 . will include the Metropolitan t I . (Mary Ann Street, Ultimo) tions f ' t ^ ° stage an exhibition of computers, Water Board, the Sydney Stock I(, State Govern- . Exchange, the as well as providing visitors with IÍn1111iI1i111U11f (hl 'hands-on' computer experience ment Information Office and lÍlllllhl14 1111111111111111111 in its new 'computer lab'. various business houses. For further information con- series 33 fashion. A variety of displays and High. speed The unit has three modes of workshops will be held in shop- tact Hartley North, Executive Secretary, Information Tech- printers for operation, the control, transfer ping centres throughout Sydney, and print modes. It also responds as well as at the Institute of nology Week, P.O. Box K701, HP 3000 series Haymarket NSW 2000. (02) to self test commands which Chartered Accountants, the result in remote initiation of Place 218-8080. BDS has introduced a new OTC showrooms ín Martín controlled internal diagnostics. and local council chambers and microprocessor system which gives Long line drivers, which are printer printer to be by the Industrial standard, allow the Computer Organised users of HP 3000 series from the Presentations Group of Com- located up to 200 metres 30/33/40/44/64 computers system. games panies, the exhibition will be printing speeds up to both trade and the The range of Dataproducts' spectacular open to the 1500 Ipm. which are supplied on mornings of band printers, public; the with Australia's first major August 18-19 entry will be The HPC-33L controller in conjunction the controller,' 1000 and computer games restricted to the trade. includes a Z80 microprocessor have speeds of 300, 600, exhibition, Electronic and For more details, contact In- and an Intel 8291 talker -listener 1500 Ipm. andToys for interfacing with the HP For further details contact Computer Games dustrial Presentations Austra- Pty will be staged at the lia, 4/389 Victoria Avenue, general purpose interface lines. BDS Computer Australia '83, 445 Toorak Rd, Entertainment Chatswood NSW 2067. (02) The printer is daisychained with Ltd, 8th Floor, Sydney Toorak Vic. 3142. (03)241-8901. Centre from August 18-21. 412-4124. other peripherals in the standard 28 - July 1983 ETI Plato and the home computer Stop was 'ng Plato educational courseware, originally developed by the Control Data Corporation for use in schools through terminals connected to a mainframe computer, will be time program available laterthis yearon diskettefortheTexas Instruments 99/4A home computer. editing. There are 64 packages, offer- To take advantage of the Plato ing mathematics, reading and software, TI -99/4A owners will grammar programs for students need a Texas Instruments in Years Three to Eight, and 44 peripheral expansion system, a packages covering mathematics, memory expansion card, a disk writing, science, social studies memory drive, and a disk con- Start VEDIT-iñg! and reading for Years Nine to 12. troller card. The initial Plato package in- Also soon to be available for cludes an interpreter solid-state the TI -99/4A homecomputer are cartridge and diskettes contain- 15 educational software car- ing a survey to help parents or tridges, featuring mathematics teachers select courseware for learning exercises for children in individual needs. For those not the kindergarten to Year Nine If you spend hours a week working on a familiar with the operation of the age group. and computer, there is a program For further information con- terminal or computer, editing programs designed to teach beginners how tact Texas Instruments Aus- you're not using VEDIT full screen text editor, to use the TI -99/4A keyboard. tralia, 6-10 Talavera Rd, North working too hard! VEDIT's These Plato packages will cost Ryde NSW 2113. (02) then you're $49.95 each. 887-1122. combination of wordprocessing, powerful macros and full screen (visual) mode will slash your programming and reediting time. Here's Colour video how VEDIT will help you get the job done display processor faster: E Blocks of your program can' be moved or Texas Instruments has a new copied within a file. video display processor, designed to interface Automatic indenting for structured between a microprocessor programs such as PASCAL or 'C'. and a PAL video colour E Reformatting of paragraphs between set monitor. margins. The new TMS9929A has four to the display modes, graphics 1, Supa edit Any portion of the text may be sent graphics 2, multicolour and text printer. mode, displaying information in Supa Edit, by eei is a key will `undo' the mistake 15 colours. As well, using an pówerful enhancement to The `UNDO' advanced planar representation, level II BASIC's `edit' and you just made - before it ruins your text. one can simulate objects in three `list' commands and is VEDIT is fully customisable to a huge dimensions. designed to suit the needs range of terminals. (Write for a full listing) Low cost 16K -type dynamic of the serious programmer/ memories are used for storage of hobbyist. The powerful command structure includes the display parameters and the for TMS9929A does an automatic It is claimed that Supa Edit search and replace, macro commands and transparent refresh of the will improve programming speed repetitive command sequences and dynamic RAMs. and is suitable for both Tandy functions. A unique graphics feature of TRS-80 and DSE System 80, special the TMS9929A is the special Model I and Model III, 16K, 32K Sophisticated buffering enables editing of animation patterns called sprites and 48K tape based systems. A files larger than main memory. which provide smooth motion lower case -driver is also included and multilevel pattern over- for Model I systems. I laying. Up to 32 sprites can be This machine language pro- displayed on the screen at any gram occupies less than 0.5K 0 (` dr 6a one time. of user memory, especially Interfacing to most 8 -bit or important to users of 16K Nepa9$ 16 -bit microcomputers is easy, systems, and is simple to operate. J vOZQ2\3 using a minimum number of The introductory price, includ- Jpc1 external components. ing sales tax, package and ,`d52J The chip is available now for posting is $14. Send payment to $35 from Texas Instruments Elite Electronic Industries Australia Ltd, 6-10 Talavera Pty Ltd, 36 Luxmoore St, Rd, North Ryde NSW 2113. Cheltenham Vic. 3192. (03) Cnoe ` (02)887-1122. 583-1201. 31'1?00o+gota . dd`es . Sosr°cQsae Peeae . egg. P0 aP65\GOae. Printout Games cartridges' for Intellivision and V IC20 (magic has released three new games cartridges for the Intellivision system and two for the popular VIC-20. Dracula, Ice Trek and Tropical volcano -infested island and must Trouble are for the Intellivision. rescue the heroine. Plagued by Dracula features the legendary snakes, man-eating clams, hos- count who prowls the night in tile gorillas and spitting lava, search of sustenance, pursued by this game requires co-ordination, ravens, wolves and the law. If quick reflexes and stamina. daylight dawns, he's finished! Demon Attack and Atlantis Ice Trek makes you the hero are for the VIC-20 - and it fighting your way across icy doesn't take much imagination wastes dodging caribou and to guess what they're like. snowdrifts. With an ice hook and Further information can be ob- fire torch you must build and de- tained from Don Dennis, Imagic, fend an ice bridge. P.O. Box 300, Forestville NSW _..0#1'16 In Tropical Trouble you are 2087. (021981-2744. ti marooned on a swamp -and- J Apple gains injunction against the Wombat! Apple Computer has been granted a court order by the SupremeCourt of New South Wales, prohibiting a High-speed joystick microcomputerdealerfrom selling microcomputer copies of the Apple computer. Discwasher, an American company previously associated with record cleaning accessories, has expanded its The dealer, Microeducational, are gratified by the Supreme product range tocater for the video game andcomputer of Newcastle (New South Court order. As a precaution, we accessory market. Wales), also agreed to pay the recommend that prospective Heading the new range is the scores than with a normal court costs involved. purchasers of personal com- Pointmaster, a joystick that joystick. The microcomputers in ques- puters or accessories which plugs into Atari and Commodore Also available is a rapid-fire tion, the Golden II and the might violate copyright laws VIC-20 game centres. It features adaptor ($14.99) which allows Wombat, contained substantial check first with Apple Com- a high-speed thumb trigger, the joystick to be fired continu- parts of theAutostartand Apple - puter, or any of our authorised comfortable handgrip, self- ously, like a machine gun. soft ROMs, which are Apple dealers. In some cases, pur- centring mechanism and a 1.5 m The Discwasher range is Computer's intellectual prop- chasers are often misled by cord. It costs about $29.99. handled in Australia by Arena erty. statements such as `compat- The manufacturer claims the Distributors, 642 Albany High- Commenting on the order, ability "with programs for the Pointsmaster has a very fast way, Victoria Park WA 6100. David Strong, general manager Apple, reaction time, enabling the oper- (09) 361-5422. of Apple Computer, said, "We ator to achieve much highergame HARD DISKS AT FLOPPY PRICES We hove o limited quantity of 6.37MB (unformatted) 5' Winchesters available of the special price of only $649 each* These drives ore from o leading USA manufacturer and carry a normal warranty. There is no catch, they ore simply lost year's model! In addition to having a much larger capacity than floppy disks, hard disk drives hove a much foster access time cnd are more reliable. At our special price the cost per byte is extremely low. The drive we ore offering has the standard ST -506 interface and con be driven from hard disk controllers such os the Western Digital 1001 (which we con also supply). Don't miss out on this excellent offer, order today from Pennywise Peripherals, 96 Camberwell Rd, Hawthorn East, Vic, 3123. M'1=lYrl %M1 q1= P.O. Box 398, Camberwell, Vic, 3124. AUSTF1ALI A Phone (03) 82 2389. Telex AA31820. 30 - July 1983 ETI How can I write better software, Sinclair ZX Spectrum software faster? Gloster Software has new that sets up the text for 48K only. software packages for the Up to six A4 pages per text file Write it in BASIC/Z! Sinclair ZX Spectrum. can be saved and loaded during program operation. ($24.50) BASIC/Z. A new standard in compilers for the CP/M system. BASIC/Z is the most Gloster Software has been Gloster Software also provides powerful implementation of the BASIC language available. BASIC/2 generates executable machine code devoted exclusively to the ZX the means of loading ZX81 saved compatible with 8080, series, 8085, Z-80 under CP/M 80 and 8086/8088 processors under CP/M 86 providing original soft- programs straight into the ZX and MS-DOS. ware which is both serious and Spectrum ($14.90). Syntax testing as you type. BASIC/Z has a entertaining. powerful program editor with 'Matcalc', the first of the ZX81 built in syntax testing as you type. Time saving features include global 'Display' handles over 300 series to be upgraded for the ZX search and replace, fifteen local edit commands and extensive debugging user -defined characters on screen Spectrum, is a spreadsheet calc- facilities. Line trace, error line retention, and the unique ability to 'single at the same time. Display and ulator. ($14.90) step' a program with a continuous display of selected variables are just a few of the features which will printing can now employ 64 alphas All software is on cassette and save you time. or numerics per line. Fast and Multitiered error handling allows your program to trap logical errors, can be obtained from Gloster including previously fatal smooth animation in BASIC are Software, BDOS errors. Only BASIC/Z can trap that 'BDOS GPO Box 5460CC, ERROR ON A: READ ONLY' before it happens. also possible. ($14.90) Melbourne Vic. 3001. (03) Printer/terminal customizing is built in. The runtime library of BASIC/Z 'Protext' is the text processor 232-2398 after business hours. (included in the package) includes installation routines for the majority of CP/M machines on the market. Your software will have near universal application without further modification. Just one set of programs will run The Gospel con practically any hardware. Unsurpassed accuracy. Floating point numerics with a range of 1 E-61 to according to management seminar on August I E+61, with a choice of precision from six to eighteen digits. All floating James 1. The fee for the one -day point maths are performed in decimal (BCD), avoiding rounding off errors. seminar is $340; the full five days Powerful executive functions aid programming. Using SORT, it can sort 2,000 elements in James Martin,the cost $1195. two seconds. User defined functions are fully recursive, support multiple arguments and may contain an unlimited number of computer industry's most Guest speakers include Dr statements. Vance Gledhill, widely read author and co- managing direc- No Royalties. BASIC/Z has no royalties nor runtime torof WicatCom puterof charges. The license founder of the DRAT W Group Austra- agreement confers the right to distribute support software such as the and of Database Design, will lia, and Dr J. C. Mudge of the BASIC/Z runtime module and the installation hardware configuration host CSIRO Division of Computing utility, subject only to specified copyright acknowledgements. alive -day data- What does it all cost? processing seminar in Research. BASIC/Z documentation & Software: $495 inc. tax. For further details, contact Available from your computer supplier of from Software Source direct. Melbourne from August 1-5. Doll Martin Associates, 131 Available on 21 days app oval (if software seal not broken). Or clip out the coupon and send in for further details. The program will open with a Walker St, North Sydney NSW self-contained one -day senior 2060. (02)923-2233. CONVENTIONAL BASIC/Z COMPILER The Aussie Byte DMA, two Winchester hard disk Í interface ports to suit WD 1001 EDIT/SYNTAX The Aussie Byte is a new and Konan controllers, D/D, D/S CHECK & single board computer, floppy disk controller (max eight COMPILE drives), (NO LINK REO) totally designed and voice synthesiser, video with 24 lines x manufactured in Australia. 80 characters display and high resolution COMPILER It has been designed specifically graphics and light pen input etc. DEBUG for the high performance, single More information about Aussie and multi-user operating systems Byte (The Great Australian such as CP/M 3, MP/M Il, Byte) can be obtained from RDM CPNET 1.1, TURBODOS etc. Computers Pty Ltd, 225 High The board incorporates 256K St, Northcote Vic. 3070. of RAM, four RS -232C serial (031481-0136. ports. Z80A CPU at four MHz. Club Call LINK If any DGZ-80 computer owners in Queensland are interested in forming a users' club could you please contact Peter Grimes, 6 landra BASIC/Z produces St, Strathpine, Brisbane Old. 4500. For more information phone (07)205-4597, direct machine object code, NOT P -CODE. It is better faster The and Newcastle Microcomputer Club meets on the second and than CBASIC or fourth Monday of each month at 7.30 pm in room G12 of the Physics Microsoft BASIC. Building at the University of Newcastle. The club publishes a monthly newsletter. Members own a variety of microcomputers; the club is not devoted to any particular brand or type of microcomputer. Anyone interested in further information should contact Angus Bliss on (049)67-2433 bh or Tony Nicholson on (049)52-6017 ah. Proe 0P5\GIZ clt NVI 2p2¡,o o Ed9 eloto c ..5/,' A oX ..... 10 ér`dme Name ies P ó Glover & Assoc. SS/1 r)- rri. t . 2_s e_. 1.1-P 1,00111,0011c USER MANUAL =: Qe . Aft 13 . 41' 'r: trt 4Y'- "4: t 1' S cgs'. ea \!. . J _ i; VZ 200 > 8 0 EL. ! 3 OP 0 I. T Y .r M+ 6 M J D 13 K O D A S p H\ . 8 A x C V Dick Smith's VZ200 personal colour computer Jamye & Roger Harrison Since Clive Sinclair dropped his ZX80 and 81 'toy' computers on an unsuspecting and unprepared market, there's been a rush, no -a stampede, to expand the features of personal computers and contract the price. The VZ200 currently sits right at the forefront. What does it offer? THE VZ200 packs an amazing number of The VZ200 measures just 290 mm wide by the Dick Smith catalogue shows), like many features ín such a tiny package: 8K bytes of 163 mm deep by 50 mm high overall. The of the colour home computers available. The memory (RAM), 16K Microsoft BASIC in keyboard is on the sloping front apron and all text format is 32 columns across the screen medium ROM, colour graphics - eight colours in the attachments plug into the rear. It is pow- by 16 lines down. In what they call medium resolution and four in higher resolu- ered from a 9 Vdc plugpack. Along the rear resolution gráphics mode you get 64 pixels tion, programmable sound generator with apron are the following connectors: dc input (blocks) across the screen by 32 down, x 64 (i.e: double) in the 'high resolution' 21/442 -octave range and nine different note du- socket, cassette recorder jack, monitor out- 128 rations, 45 -key moving -key keyboard (with put, expansion connector, peripheral con- mode. auto -repeating keys), both RF output (to TV nector and TV (RF modulator) output on In the medium resolution mode, you can antenna input) and direct video (for a channel 36 UHF. program a block to be any of eight colours - monitor), inverse video and on -screen cur- The video display only uses about three- green, yellow, blue, red, buff, cyan (a blue), sor -controlled editing. quarters of the screen (unlike the picture in magenta or orange. They're what's called the 32 - July 1983 ETI 'foreground' colours. The background (i.e: models being widely available - and the style keyboard as you keep cracking your the rest of the screen area) can be prices either are continually coming down. finger on the case below the keyboard! It green or orange in this mode. The VZ200 is supplied with all cables in takes a little getting used to. We also took a In the higher resolution mode, you can generous lengths, a plugpack, a User Man- little time to learn not to confuse the SHIFT program any block (foreground) to be any of ual, a demonstration program on cassette, a and CTRL keys. There are other problems only four colours- green, yellow, blue BASIC or red Reference Manual and a booklet of with the keyboard that relate to its partly - with the background colour green, or with BASIC Applications Programs. non-standard layout, but if you're a beginner the background buff you can program the in the personal computer stakes it's unlikely blocks to be buff, cyan, magenta or orange. to be a worry. The programmable sound generator has a the The single -key entering of statements and range of 31 notes over 25,2 octaves from From user's view A2 to commands was an idea introduced by Clive D#5, plus a 'rest'. There are nine For all the programm- functions packed into the key- Sinclair with his ZX80, forerunner to the able note durations of 1/8,1/4, 3/8,1/2, 3/4,1, board, the key is a operation big let -down. ZX81 and Spectrum computers. a 154, 2 and 3. It's good The keys are rubber -buttoned microswitches idea, taken to its logical limit with the The text character set comprises 62 of the and while they do have movement, the VZ200. Strictly, you need to use more than standard 64 -character ASCII table, 5 x 7 dot feedback via your finger can only be des- one key to enter a command, statement or matrix format. The two you don't get are cribed as uncertain. graphics character, but only three at the hardly important in this' application. Thirty We've criticised this type of keyboard in most; e.g: to get the PRINT command you of the keys on the keyboard have four 'shift' the past and can't help but think that, where push CTRL and P together. To get the levels as can be com- - seen from the accompany- a cost compromise is necessary, an elasto- mand or ing pictures. With statement under a key, you hold the exception of the RE- meric keyboard (like that on the ZX81) is down CTRL and TURN, press RETURN, then the SPACE, CTRL and SHIFT keys, the preferable. The computer gives a'beep' when key you want. rest have three levels of shift. That is, apart you press a key (except for the CTRL, SHIFT The direct video output into a Philips 20" from obtaining the normal character when and RETURN keys), which helps, but the colour monitor is good, but plagued by pat- you press a key, you can get more functions, key action is so light that double -keying is terning that ripples seemingly such as a graphics diagonally character, a BASIC com- common. The auto -repeat feature, however, across the display. mand, an operating The display is noticeably command or a program is a good idea. The key will repeat the charac- inferior when using statement. the RF output into the ter or command if you hold it down for longer TV set's antenna. However, it is better than Four keys act as cursor control keys in the than one second. some other popular colour computers CTRL mode, these being the four on the right The on -screen editing functions are very around. For the price, it's acceptable. of the lower rank. The L and ';' keys provide good -a real boon to the beginner program- The VZ200 uses a Z80 microprocessor, the INSERT and RUBOUT editing functions mer. The usual BASIC editing feature of probably the most widely used microproces- in the CTRL mode. The colour programming simply retyping a crook line works, but that sor in all the personal computers produced to command keys, 1 to 8, are labelled and can be time-consuming, especially with long date. The specifications say colour -coded. it runs at lines. The VZ200 allows you to move the 3.58 MHz. However, it's not all that fast, but The expansion connector will accom- cursor around and re -type incorrectly en- ís probably quite fast enough to manipulate modate such things as a memory expansion tered characters, commands or statements. simple graphics effectively. module. A 16K module is available for just With the latter two, the single -key entry fea- If you really want a $79, allowing to know, FOR -NEXT expansion of the user memory ture is a real time-saver. We would rate the loop takes four milliseconds, which to 24K. in today's editing facilities as one of the VZ200's major computer world is pretty slow. As it really is The peripheral connector is for plugging in features. a beginners' machine, that's no real disad- such things as a printer and interface, one is The keyboard has an enlarged SPACE key vantage. If you're thinking of ploughing available for $49.50, permitting the attach- at the right of the lower rank. This is a prob- through your maths homework with it, a ment of a standard Centronics printer, many lem if you're used to a normal typewriter - pocket scientific calculator is faster. Continued on page 37 MODE I0 COLOR GREEN C SAYE CLOAD C RUN VERIFY LIST RUN ENO NEW READ DATA /111/33 POWER SIN I COSI TAN I ATN ( LOG ElP( SON T SORT ABS I /NT I FOR TO NEXT RETURN THEN ELSE IF INPUT LE PRINT o 1 CNN S I vAL I LEN I LEFT S 1 MID S I RIGNT SI INKEY S AND OR NOT MODE I STEP DIM GOSUB GOTO CLS REM TABI IZMIR EMI= L ASCI STRSI RESTORE RNO( STOP SET RESET POINT PEER I PORE CONY L PRINT LUST COLOR 0 1c INP OUT COPY USA SOUND USING ETI July 1983 - 33 The coup V. of Lieutenant ilson. ed 20. When you talk to Geoff Wilson about his 18 months in the Army you can't help but feel he's a young man who's come a long way in a short time. Already he's graduated from Officer Cadet School, Portsea, with a commission as a Lieutenant. And already he commands an Infantry Platoon of thirty men. It's a tremendous responsibility. Especially for a 20 year old. But as Geoff says, "You get enormous satisfaction from using what you've learnt in your training to help bring out the best in your team. And in achieving results together:" "Obviously situations which I haven't had experience in crop up all the time. And that's when I have a real responsibility to myself and my men to make decisions based on sound knowledge rather than guesswork. As a result you constantly find yourself learning and mastering new skills: And that's a challenge I always enjoy accepting. You really begin to realise your full potential and believe in your ability." "I suppose you might say my decision to take on a career as an Army Officer is my personal `military coup'" "It's hard to visualise another career as exhilarating, varied and satisfying. Or which provides as many opportunities to be recognised and rewarded for a job well done" "Think about it carefully. I know I did before joining!" Armour, Artillery, Engineering, Survey, Signals, Transport, Infantry, Intelligence and Aviation are just some of the fields open for you to enter. If you're aged between 181/2 and 23 on entry (or up to 25 with a degree or diploma), have your HSC or equivalent, (at a level acceptable to the Army), and think you have what it takes to pull -off Poi y your own military coup, For more information post coupon lo GPO Box Sydney XYZ, contact your nearest 212 1011, Newcastle 25476. \Lollongong 286492, Albury 552248, Lismore 216111, Canberra 82 2333, Army Careers Recruiting Melbourne 613731, Geelong 21 1588, Bendigo 438008, Ballarat 31 1240, Brisbane 2262626. Townsville 724566, Adelaide Centre or fill in the 2121455, Penh 3256222, Hobart 347077. supplied coupon. Launceston 31 1005. There are two Name courses per year. Address Applications close mid - Postcode Phone March for á July entry Binhdate Educ. Std. and early August for Army a January entry. Officer. A leading profession. All enquiries treated la waaar.. in confidence. as7.tp5.53 Authorised by Director -General RmuidnR. Department of Defence. J i bfLY . 111111111111 _ e;G?. // r Medfly can tax your mind, mind your tax, and let yoU play in space. The Medfly home computer is Games and Adventure Games, compatible with the largest library of which you can plug straight in to software available today. What this your home TV screen. opens up to you and your family is Medfly is a thinking machine to simply amazing. expand young minds; a working For your children - education machine for home or business packages on Algebra, Spelling, accounting; a games machine for Mathematics, Vocabulary - family fun. And above all, Medfly is a making your Medfly virtually a home value machine, with quality coach or tutor. electronics by Siemens and with For personal and business use - more features, capabilities and add- you get access to Time on potential than many costlier Management, Business Systems, microcomputers. Accounting Packages and Financial The basic Medfly microcomputer Broadsheets. system - alpha/numeric keyboard For family entertainment - you'll and processor - is available now for be able to share the fun just $1,995 including of Action Games, Strategy MED FLY sales tax. putting the value buzz into home computing VICTORIA: Medfly Basis (Vic.) Pty. Ltd. 43 Atherton Rd. OAKLEIGH, VIC. 3166 PH: 569 0169. O ALL OTHER STATES jD,Ú VI9J32.ibia 2/190 George Street, PARRAMATTA. PH: (02) 689 2599 SUMMARY OF BASIC COMMANDS PRINT Functions: RIGHTS Right characters - PRINT TAB INKEYS - Check keyboard 1) Arithmetic operators PRINT USING 5) Logical operators PRINT @ LET 2) Relational operators Relation and logical expressions have value 1 if true, DATA A NOR 0 if false. NOT READ RESTORE 3) Arithmetic functions: 6) Graphics and sound functions: 8) Commands: SOR - Square root CLS - Clear screen LIST INT - Integer part SET - Plot a point RUN RND - Random number RESET - Clear a point NEW ABS - Absolute magnitude POINT - Return the color code CONT SON - Sign COLOR - Set color VERIFY - Check whether program on tape and memory COS - Cosine SOUND - Produce tone of different frequency and duration are equal SIN - Sine MODE - Select graphic or text CLOAD - Load program on tape EXP - e' CSAVE - Save program on tape Program TAN - Tangent 7) statements CRUN - Load program on tape and run LOG - Natural logarithm DIM - Dimensions CTRL RESET - To halt program ATN - Arc tangent STOP 9) Other Statements END 4) String functions: location specified GOTO PEEK - Return the value stored at the a into a specified location LEN - Length GOSOB POKE - Load value ST RS - String of numeric argument RETURN LPRINT - Print on line printer line printer VAL - Numeric value of string FOR ... TO ... STEP LUST - List on from ASC - ASCII value NEXT INP - Return the contents read ports CHRS - Character REM OUT - Send values to ports LEFTS - Left characters IF ... THEN ... ELSE COPY - Copy the content on screen to printer USR Call the users assembly language subroutine M I DS - Middle characters INPUT - Documentation As Microsoft BASIC is used - the erst- Cassette comments while 'industry standard' - there are huge The BASIC Reference Manual and the two amounts of published programs and many, A pre-recorded cassette with cute demon- booklets supplied with the VZ200 are gener- many books on the subject that will keep you stration software comes with the VZ200. For ally well produced, clear and understandable occupied for ages. one thing, it shows that the cassette - which is just what the raw beginner A booklet of applications programs is in- interface is quite good, as reliable loading wants. cluded with several dozen short programs was no problem. The BASIC Reference Manual is spiral that are not only interesting and amusing, As the VZ200 is not a games/computer bound, which facilitates laying it open so the but instructive and perhaps useful to boot. machine, the pre-recorded software base is pages sit flat. However, the spiral binding is Many would be good 'starting points' for de- only going to be available on cassette, as just slightly too small for the number of veloping programs of your own devising or there's no ROM socket. At present, there's no pages and it's a bit of a bind trying to turn useful as subroutines within your own pre-recorded software available, but, from them. programs. past experience, that's probably a situation This manual covers all the functions and Absolutely no technical details, not even a that will rectify itself. operations of the VZ200 in a fundamental memory map, are given, but we guess that There are lots of 'freelance' software pro- way, with some programming examples. such things might appear in some 'support' ducers in the market supplying software for You are encouraged to learn by trying things publications. existing machines who will doubtless get be- for yourself. We found a number of small hind the VZ200. errors, but nothing disastrous. For example, the method of using the IN- The BASIC SERT command when editing does not work The 16K Microsoft BASIC included can only Conclusion the way it's described in the book. Say you be described as excellent - outshining the The VZ200 is very reminiscent of the Sin- typed PRIT instead of PRINT. The book says mechanical and electronic constraints of the clair ZX81/Spectrum or National JR100 you do an INSERT by moving the cursor up VZ200. But, we have to keep reminding (which is sort of rare here, as yet). It has a to the character before the place you want to ourselves that this is really a low cost begin- very great deal to offer in price, functions insert a character (that is, 'I' here), type ners' machine. The range of commands, etc, and features. The major disappointment is CTRL INSERT, then type the required available, and the flexibility of the language, the keyboard, but all low cost home com- character (that is, 'N' here). However, that stand out. Learning to use the facilities is a puters compromise here and it's a matter of gives you PRNIT! breeze. The buzzword is 'user friendly'! preference whether you favour one type of What you really have to do is cursor up to All the BASIC commands, operators and cheap keyboard over another. the character after the place where you need statements are shown in the accompanying The big question is, would you do any bet- to insert a character, then do the insert panel. Those of you who know will see that ter at $299. You'd almost certainly get a bet- routine. it's all pretty standard fare. However, it's ter keyboard, but we haven't yet seen any- such The reference manual lists all the avail- good to see the inclusion of things as thing in that price range to compete with the able text characters and BASIC statements, IF ... THEN ... ELSE statements and the features and memofy capacity of the VZ200. or^ -.tors and commands, with some brief COPY statement (otherwise known as a Judging from the phenomenal success and e .planations. An error message list is given, 'screen dump'). Seeing that USR is included popularity of other 'bottom end of the but incredibly, no explanation of what they for the benefit of using machine code in market' computers, such as the ZX81, all mean or what to do when you get one! BASIC programs, we can only hope that Spectrum and VIC-20, there are huge num- Grrr. some suitable books or manuals on the sub- bers of people who want a low cost computer For all its good points, the manual con- ject, specifically for the VZ200, will appear at just to 'get started', or get their children tains no detailed index, which would be very some later date. started, in computing. useful for a beginner. The contents list is at ' Programming using graphics or sound is least comprehensive, so that's a plus in its relatively simple. The graphics commands Price is all-important to people who don't favour. are simple, largely because of the 'chunky' want to pay a great deal of money to learn What happens when you've worked your graphics employed. You'll find no DRAW, what the subject's all about before 'getting in way through the reference manual? Well, PAINT, LINE or CIRCLE commands here, deeper'. Compromises are acceptable there- you won't be a hot -shot programmer, but you but what you do get is effective for the sort of fore, and our criticisms should not be taken will have gained an understanding of pro- graphics included in the machine. It's best to too much to heart. For its price, the VZ200 gramming and be able to tackle some pro- crawl before you walk, and it's a beginners' has a great deal to offer, and from such small grams of your own invention, plus modifica- machine, remember. Similar sentiments ap- beginnings one can go on to 'conquer the tions to published software. ply to the sound programming. world', or at least a comfortable niche. ETI July 1983 - 37 ROD IRVING ELECTRONICS 425 High St. Northcote, Ph.: (03) 489 8131 2 BRANCHES: 48-50 A'Beckett St. Melb. Ph.: (03) 347 9251 Errors and omissions excepted. Mail orders: P.O. Box 235 Northcote, Vic. 3070 min p&p $3.00 INSULATION DISPLACEMENT COMPONENT CARRIERS LOGIC BOARD SOCKETS CONNECTORS PC MOUNTING HEADERS 4 PRICE 1-9 10+ 1-9 10+ P10915 15/30 .156'S.T. 6.95 6.50 P12148 8 Pin Component Carrier 1.75 1.50 P10918 18/36 .156'S.T. 6.95 6.50 P12152 14 Pin Component Carrier 1.95 1.70 P10920 20/44 .156'S.T. 7.95 6.95 P12154 16 Pin Component Carrier 2.25 1.95 P12156 18 Pin Component Carrier 2.75 2.50 LOW PROFILE IC SOCKETS P12158 20 Pin Component Carrier 3.50 3.10 PRICE P12160 24 Pin Component Carrier 3.95 3.50 Economical Soldertail PRICE P12162 28 Pin Component Carrier 4.95 4.50 1-9 10+ 1-9 10+ P12164 40 Pin Component Carrier 5.95 5.40 P10550 8 Pin .25 .20 P10560 P12010 10 Pin S.T Header 3.95 3.90 14 Pin .35 .30 P12011 10 Pin R.A Header 3.95 3.50 25PIN "D" CONNECTOR P10565 16 Pin .40 .35 P10567 P12020 20 Pin S.T Header 5.95 5.25 10C CRIMP 18 Pin .50 .40 P12021 20 Pin R.A Header 5.95 5.25 _ P10568 20 Pin .50 .40 P12026 26 Pin S.T Header 6.95 6.25 P10569 22 Pin .50 .40 P12027 26 Pin R.A Header 6.95 6.25 P10570 24 Pin .50 .40 I P12034 34 Pin S.T Header 7.95 7.25 \ P10572 28 Pin .60 .50 P12035 34 Pin R.A Header 7.95 7.25 P10575 40 Pin .70 .60 Precision P12040 40 Pin S.T Header 8.95 8.25 PRICE Machined Gold Insert 40 Pin 1-9 10-25 P12041 R.A Header 8.95 8.25 1-9 10+ P12050 50 Pin Header 9.95 P10620 8 PIN 1.20 1.00 S.T 8.95 P12170 Pin Plug Crimp 12.95 11.95 P12051 50 Pin R.A Header 9.95 8.95 25 P10624 14 PIN 1.60 1.40 P12171 25 Pin Socket Crimp 13.95 12.95 Mounts on PCB and Mates with IDC Sockets. P10626 16 PIN 1.90 1.70 P10628 18 PIN 2.00 1.80 CARD EDGE CONNECTORS CENTRONICS P10630 20 PIN 2.20 2.00 P10632 22 PIN 2.40 2.20 i P10634 24 PIN 2.60 2.40 P10640 28 PIN Edge Connectors 2.90 2.70 40 PIN to suit 4.40 4.00 Oisk Drives Etc. PRICE WIRE WRAP SOCKETS 1-9 10+ PRICE P12200 36 Way Centronics Plug IDC 12.50 11.50 1-9 10+ P12201 36 Way Centronics SCKT IDC 13.50 12,50 P12060 10 Way Card Edge Conn 7.95 7.10 P12203 Way Plug 50 Centronics IDC 14.50 13.50 PRICE P12062 20 Way Card Edge Conn 8.50 7.95 P12204 50 Way Centronics SCKT IDC 15.50 14.50 P12064 26 Way Card Edge Conn 8.95 8.10 1-9 10+ P10579 8 Pin 1.20 1.00 P12066 34 Way Card Edge Conn 9.95 8.95 P12210 36 Way Solder Plug 15.95 14.50 P10580 14 Pin 1.20 P12068 40 Way Card Edge Conn 11.50 10.50 P12211 36 Way Solder Line SCKT 15.95 1.40 14.50 P10585 16 Pin 1.60 1.40 P12070 50 Way Card Edge Conn 12.50 11.50 P12213 36 Way Solder SCKT 15.95 14.50 Chassis P10587 18 Pin 1.90 1.70 WIRE WRAP HEADERS STRIP HEADERS P10590 20 Pin 2.20 2.00 P10592 22 Pin 2.40 2.10 30 Way Male .i' a .1- Matrix P10594 24 Pin 2.50 2.20 P10596 28 Pin 2.80 2.40 P10598 40 Pin 3.30 2.90 MOLEX PINS Make your own IC Sockets. Supplied on a Breakofl Header. P12230 30 Way Single Strip Header 3.95 3.75 P10700 Pack 100 52.25 PRICE P12231 30 Way Oval Strip Header 4.95 4.75 P10701 Pack 1000 1-9 10+ 516.00 P12080 10 Pin W.W Header 6.95 5.95 30 Way Female .1' x .1- Matrix P12081 10 Pin W.W R.A Header 6.95 5.95 IDC RIBBON CABLE « f P12082 20 Pin W.W Header 7.95 5.95 This Is the Ribbon P12083 20 Pin W.W R.A Header 7.95 5.95 only Cable to use In I.D.S. or cnmp P12084 26 Pin W.W Header 8.95 style connectors. We use in our computer productions. 7.95 As P12085 26 Pin W. W R.A Header 8.95 7.95 the exact spacing and guaiky is critical for ultra reliable long P1209034 Pin W.W Header 9.95 8.95 term computer operations. Do not try and P12091 34 Pin W.W R.A Header use cheaper Ribbon Cables as you will find that the 9.95 8.95 reliability P12092 40 Pin W.W Header 12.95 11.95 P12234 30 Way Single Plug Header 4.95 3.95 doesn't justify the cheaper prices. P12235 P12093 40 Pin W.W R.A Header 12.95 11.95 30 Way Dual Plug Header 5.95 4.95 Colour is Grey with wire one being colour coded to P12094 50 Pin W.W Header 13.9512.95 match up with Pin one of I.D.C. Connectors. P12095 50 Pin W.W R.A Header 13.95 12.95 SOLDER CONNECTORS PRICE PER METRE No. of IDC SOCKETS D RANGE CONNECTORS Cond. 1-9 10-99 100+ W12616 16 1.90 1.70 1.40 W12624 24 2.90 2.60 2.10 W12634 34 3.90 3.50 3.10 W12640 40 4.90 4.40 3.90 w 12650 50 5.90 5.20 4.60 i W12660 60 4.90 PRICE eeeaerri.í}i 6.90 5.90 Y ,. 1-9 10+ WARNING P12100 10 Pin Socket 4.95 3.95 This is the type for P12102 20 Pin Socket 5.95 4.95 only of Cable to use Insulation PRICE Displacement Connectors. I.D.C. P12104 26 Pin Socket 6.95 5.95 1-9 10+ P12106 34 Pin Socket 7.95 6.95 P10880 DE9P Male 9 Pin 3.50 3.00 P12108 40 Pin Socket 8.95 7.95 P10881 DE9S Female 9 Pin 4.50 4.00 UNPROTECTED HEADERS P12110 50 Pin Socket 9.95 8.95 P10882 DE9C Cover 9 Pin 2.50 2.20 P10890 DA15P Male 15 Pin 3.90 3.50 CABLE PLUGS P10891 DA15S Female 15 Pin 4.90 4.50 P10892 DA15C Cover 15 Pin 2.50 2.20 tlx\r.\\\\\xs- P10900 DB25P Male 25 Pin 4.90 4.10 P10901 DB25S Female 25 Pin 4.95 4.50 Dual in Une 2.54mm P10902 DB25C Cover 25 Pin 2.50 2.20 1-9 10+ PRICE P10910 DC37P Male 37 Pin 8.90 8.20 P12240 10 Way Unprot. Header 1.95 1.75 1-9 10+ P10911 DC37S Female 37 Pin 10.90 9.90 P12246 16 Way Unprot. Header 2.95 2.50 P12114 14 way crimp 1.95 1.50 P10912 DC37C Cover 37 Pin 5.50 4.90 PI 2250 20 Way Unprot. Header 3.25 2.95 P12116 16 way crimp 2.25 1.95 P10920 DD5OP Male 50 Pin 90 112.901.90 P12256 26 Way Unprot. Header 3.75 3.25 P12124 24 way crimp 3.95 3.25 P10921 DOSOS Female 50 Pin 14íy..90 P12260 30 Way Unprot. Header 3.95 3.50 P12140 40 way crimp 6.50 5.95 P10922 DD50C Cover 50 Pin 6.50 5.50 P12264 34 Way Unprot. Header 4.95 4.45 P12270 40 Way Unprot. Header 5.95 5.25 P12275 50 Way Unprot. Header 6.95 6.25 100+, less 10% from 10+ price P12280 60 Way Unprot. Header 8.95 7.95 Machine language graphic driver for the ETI-640/ETI-685 Part 2 In the first part we whetted your appetite telling you what was in the graphic driver package. Now you've read (almost) all about it, here's the real thing! ... from two of the 'slacker hackers'. G.H. Secomb J.F. Adamthwaite The line shortening and flexible coordinate 4. Using a version of the Variable Duty -Cycle Rectangle function specification capability are shown in the Algorithm. This routine draws a rectangle, using the algorithm below. This method held promise of being the two pairs of user -supplied coordinates as fastest of all, but it suffered from a precision opposite corners. Conceptually quite straight- problem due to the use of integer arithmetic, forward, it constructs the coordinates for the resulting in a noticeable distortion of the other two corners from combinations of the Ellipse function circle. It also didn't seem to know when to supplied coordinates, and plots a line from The brain -strain required to come up with a stop. We only wanted one lap. corner to corner until the full rectangle is useful ellipse plotting routine caused nearly Finally, a chance encounter with two drawn, using the appropriate pixel plotting as many hairs to desert their post as did the bright young lads (these kids make us oldies mode of SET, CLEAR or INVERT. LINE routine. Several techniques were tried feel so stupid) at an establishment known as The requirements for the rectangle before the final one was selected. They were: 'Comp -Soft' in Swan Street in Richmond, functions were: 1. Calculating sine and cosine for progress- brought to light a workable solution. I will for 1. Double plotting of the corner pixels must ively increasing angles from 0 through to be forever grateful to the proprietor not occur. Each corner is the end point of one 359 degrees. This approach proved to be slow allowing me to waste his time and that of his line and the start point of the next. Double and took too much code. (Machine language workers. It saved us from needing to weave plotting during the INVERT RECTANGLE trig. is a pain.) baskets. . function would leave the corners as they 2. Using look -up tables for sines and cosines. The method has its roots in calculus. Don't were, effectively remaining unplotted. To This was fast, but required a large look -up cringe, we've already done it for you. It is get around this, each line must be shortened table, even when using a single 90 degree quite novel in the method it uses to create the by one point (see diagram below). quadrant table backwards and forwards to sine and cosine values. An explanation follows: trig. table book, 2. The user must be able to specify any of the create the sines and cosines for each of the Looking at a sine curve or opposing coordinates, as for the four quadrants. you will notice that at 0 degrees, sine = 0, diagonally first, window function, and achieve the same 3. Using coarse angle increment look -up rising rapidly with increasing angles at slowing in its ascent till rectangle on the screen. tables with interconnecting lines to fill the then progressively gaps. 90 degrees is reached where the sine value is X1,Y2 X2,Y2 This seems to be the method employed in momentarily stationary, with a maximum X1,Y1 X2,Y1 the TRS-80 colour computer, although we are value of +1. (X1,Y1)1X2,Y2) not sure of that. It was fast, but the code The 'secret' is in deriving a progressively (X1,Y2) (X2,Y1) required to avoid double plotting at the line decreasing value from somewhere to be added (X2,Y111X1,Y2) junctions proved to be too cumbersome. This to the old sine to create the new one. Where (X2,Y2) (X1,Y2) method requires greater resolution than is can we get such a decreasing value from? the These combinations should all give the possible on the ETI-640, in order to look The answer is ... trumpet fan -fare ... same results. Don't call us if they don't. convincing. cosine! * RECTANGLE FUNCTION SET X = X2 * Inout parameters are- (X1.1'1) coords Of any Corner FOR V = V1 TO (V2-YINCREMENT) STEP YINCREMENT * (X2.1'2) coords 01 0000site corner PLOT(X.Y) NEXT V IF X2 ) XI THEN %INCREMENT = +1. IF X2 = X1 THEN XINCREMENT = 0. SET V = V2 IF X2 < XI THEN XINCREMENT FOR X = X2 TO (X1+XINCREMENT) STEP (-XINCREMENT) PLOT(X.Y) = +1. IF V2 ) V1 THEN VINCREMENT NEXT X IF V2 = V1 THEN VINCREMENT = 0. IF V2 < V1 THEN YINCREMENT . -1. SET X = X2 FOR V = V2 TO (V1+YINCREMENT) STEP (-YINCREMENT) SET Y = VI PLOT(X. V) FOR X = XI TO (X2-XINCREMENT) STEP XINCREMENT NEXT V PLOT(X.Y) END. NEXT X ETI July 1983 - 39 Going back to our trig. table again it will You will notice spontaneously, if nudged, There is no correct value, merely values of be found that the cosine has a maximum that the divisions can be done in machine greater or lesser convenience. value of +1.0 at 0 degrees, progressively language as simple right shifts, as long We chose a value of 128 to keep the pre- decreasing towards a value of zero as as the divisor, in this case PORTION, is a cision high. It gives the maximum usable 90 degrees is approached. If a small portion simple power of2. e.g: 32, 64, 128 etc. precision for the ETI-640 and could be of the current cosine value is added to Increasing values for PORTION give more regarded as the practical upper limit here. the current sine value, it will yield the new plotted points along the perimeter of the At a radius of 140, the circle has a diameter sine value. circle, allowing circles of larger radius to of 280 and wraps around the screen due to Fine. So where do we get the new cosine be plotted without gaps. This also causes byte overflow. It is a simple matter to alter value from? the values of SINE and COSINE to be altered the precision if desired. Notice that the amount by which the cosine in smaller increments, more closely approx- The final algorithm presented now is decreases is progressively increasing as imating a true differentiation function, identical to the machine code version. The 90 degrees is approached. (Yes, it is a mouth- resulting in a rounder circle at the same penalty for ellipse plotting capability is the ful.) In other words, an increasing value is time. Very helpful if circles are round, it is. need for two multiply operations per loop, being subtracted from the cosine at each Saves overworking your imagination. Sadly, which slows it considerably. Unfortunately step. Where can we find a number which just you must sacrifice speed if you want large we must do true multiplies, not just left shifts. happens to be increasing? circles or high precision. Try experimenting. In this version 'correct' values for sine and The source of a suitable increasing value is The final value of PORTION chosen for the cosine are kept in the variables SINE and found to be the sine (surprise, surprise). machine language version is 128 (2 to the COSINE with values between +1 and -1. We therefore take a small portion of the power of 7). This allows circles with a radius These values are multiplied by the vertical sine value and subtract it from the old cosine of up to approximately 140 to be plotted with- and horizontal radius and added to the ellipse to give the new cosine value. out gaps. (That's huge.) If your application centre coordinates to give the final plot point The pleasant feature of this approach is doesn't require such large arcs, a doubling of coordinates. Remember, this happens some that the method follows through into the speed can be obtained by selecting a value for 804 times per circle if PORTION is set at 128. second, third and fourth quadrants without PORTION of 64. A value of 32 would further A comparison to the previously plótted the need for any further trickery. double the speed but the maximum radius of point is performed to ensure freedom from Further subtractions from the cosine 35 (now) is starting to become restrictive, double plotting. Some twiddling to the loop value after 90 degrees is reached make it and the circle gets a little slanted to one side. counter eased testing for the exit condition. swing negative, and further additions of a portion of this negative cosine to the sine value make the sine start dropping from +1 * ELLIPSE FUNCTION * Input variables are - XCENTRE X coord of ellipse centre zero, and so on. a towards In this way, the - YCENTRE V coord of ellipse Centre values of the sine and cosine leap -frog right w - HRADIUS Horizontal radius around the circle, eliminating the need for - VRADIUS Vertical radius a traditional calculations based on known LET SINE = 0. angle. The information required for the next LET COSINE = 1.0 point is extracted from the previous point LET PORTION = 128 values. Wake up! LET XPLOT = XCENTRE + HRADIUS (Plot first point) Before tackling the final algorithm chosen LET YPLOT = YCENTRE for circle and ellipse plotting, a simplified PLOT(XPLOT,YPLOT) version will be examined. This version is a FOR COUNTER = 0 TO 3.14159 STEP 1/256 'stripped' example of the 'bells and whistles' model. It has the advantage of significantly SINE - SINE + COSINE/PORTION greater speed due to the lack of multipli- COSINE = COSINE - SINE/PORTION cation operations, sacrificing the ability to NEWXPLOT = INTEGER (COSINE * HRADIUS + XCENTRE + 0.5) draw ellipses. If only circles were needed, NEWYPLOT = INTEGER ( SINE * VRADIUS + YCENTRE + 0.5) and speed was vital for a particular applica- tion, it could be used in place of, or better IF NEWXPLOT = XPLOT AND IF NEWYPLOT = YPLOT still, in addition to the ellipse function. THEN COTO NEYT-COUNTER (Same as last, sails Plot) It is slightly different to the previous description in that the variables SINE and XPLOT = NEWXPLOT YPLOT = NEWYPLOT COSINE, instead of containing values varying PLOT(XPLOT,YPLOT) between +1 and -1, contain values varying NEXT COUNTER between +RADIUS and -RADIUS. The con- END. cept is the same, just the magnitude of the variables has been changed to gain speed. * CIRCLE GENERATOR ALGORITHM Software interfacing * Input varlabies are - XCENTRE X coord of circle centre The program was designed to make inter- - YCENTRE Y coord Of circle centre * - RADIUS Desired circle radius facing as easy as possible (we hate phone calls) while allowing for future expansion in LET SINE - 0. the number of supported functions, or changes LET COSINE * RADIUS in the number of parameters passed to it. LET PORTION - 128 (Speed/accuracy trade -Off value) The only absolute address you need to LET XPLOT = XCENTRE + RADIUS remember is the subroutine entry point YPLOT LET - YCENTRE 'ENTRY' at hex 6400. All the parameters PLOT(XPLOT,YPLOT) (Plot first point on Circle) which need to be communicated to or from FOR COUNTER = 1 TO the program are stored in a 6 804.2477 ( = 2 * PI * PORTION ) -byte table starting at 'ENTRY+3', hex 6403 through to SINE = SINE + COSINE/PORTION (Caic new sine) 6408, inclusive. The number of parameters COSINE = COSINE - SINE/PORTION (Caic new cosine) required to be passed depends on the desired XPLOT = INTEGER (XCENTRE + COSINE + 0.5) (Round result) function. See tables opposite. YPLOT = INTEGER (YCENTRE + SINE + 0.5) PLOT(XPLOT.YPLOT) (and plot It) Speculation This package is by no means NEXT COUNTER (Back for morel) complete, and it END. can never be so, due to the diversity of requirements in different applications. It is 40 - July 1983 ETI designed to be easily extendable and as fast as possible. Computer graphics can never be ADDRESS LABEL USE MEX DECIMAL too fast. If you have a different memory -mapped Parameters. 6400 25600 ENTRY Enter here after storing VDU, don't despair, as only the subroutine FUNCTION OP -code store. 6403 25603 Graphic 'CONVRT' need be changed to perform the 6404 25604 PARAMI 'Parameter list. 6405 25605 PARAM2 required coordinate translation. If your 6406 25606 PARAM3 VDU has a greater coordinate addressing 11 6407 25607 PARAM4 range, the use of 16-bít arithmetic will be 6408 2560E BITVALUE Result of "BIT TEST" funtlon Call. necessary. Those of you with Z80/ETI-640 are invited to try your hand at FUNCTION PARAMS RED'D PARAMETER DESCRIPTION combinations rewriting this program. 0 SET WINDOW 1.2.3.4 - Parameters 1 & 2 define One corner Hardware tricks to consider are pre- Of the desired area. programmed ROMs on I/O ports to speed up - Params 3 & 4 define the diagonally 1 CLR WINDOW 1.2.3.4 use OPPosIte corner. coordinate -to -address conversion or for 2 INV WINDOW 1.2.3.4 - As above. as look -up tables for trig. or multiply/divide - 1 is the number of text 3 PROT SCRN 1 Parameter functions. tO be Protected from scrolling. lines We chose not to do this here, as it was 4 SET PIXEL 1.2 - Parameter 1 is the X coordinate. judged to be out of the range of the average 5 CLR PIXEL 1.2 - Parameter 2 is the Y coordinate. part-time hobbyist. 6 INV PIXEL 1.2 - As above. The user should try to adapt and use the - status returned in location 7 TST PIXEL 1,2 Pixel needs. "BITVAL". program according to the application It works quite well as a Napoleon hat or a the start 8 SET LINE 1.2.3.4 - Parameters 1 & 2 define fleet of paper darts. point Of the line. Reader application examples are invited, 9 CLR LINE 1.2.3.4 - Parameters 3 & 4 define the end. We are currently 10 INV LINE 1.2.3,4 - As above. as we are burnt out. 11 N.U. threatening upgrades to the program such as macro function capability, relative coordinate - Same parameter definitions as the 12 SET RECTNGL 1,2.3,4 addressing and string processing functions. 13 CLR RECTNGL 1.2.3.4 WINDOW functions. 14 INV RECTNGL 1.2.3.4 - As above. These will most likely be added as a 'front-end' 15 N.U. program, which preprocesses the extended functions and feeds the derived parameters 16 SET ELLIPSE 1.2.3.4 - Params 1 & 2 define the X & Y coords 17 CLR ELLIPSE 1.2.3.4 of the centre Of the ellipse. to this one. 18 INV ELLIPSE 1.2.3,4 - Param 3 is the horizontal radius. A 6809 (wot's dat) version is currently in 19 N.U. - Param 4 is the vertical radius. the pipeline, and if this article makes us rich and famous, it may get some airplay as well. FLEXIBLE MPIY1 Z80 S-100 BUS MICROPROCESSOR SME is proud to present the flagship of its Unicorn series - the MPU-100. Designed for use in commercial, industrial and FEATURES engineering environments where speed and reliability are paramount, the MPU-100 features an advanced vertical Z80, 4Mhz, SBC 800. motherboard system that gives it the highest reliability Enhanced FDC floppy controller and lowest profile of any machine of its type. board. Economically priced the MPU100 can be configured to RAM perform simple single user tasks or easily expanded by DRC-II 64/256K dynamic the addition of further function boards to handle up to card. fifteen terminals and at least 50 Megabytes of hard drive. CP/M based. Attractively housed in a rugged steel based aluminium bodied enclosure the MPU-100 is rack mount compatible 10 slot vertical motherboard for and is supplied fully assembled and tested. reliability and ease of expansion. Designed and manufactured in Australia. 22 Queen Street, Mitcham, Victoria, 3132. Telex: SMELEC AÁ37213 IIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIII"I'1I ETI July 1983 - 41 EXERCISE PROGRAM - 640/685 graphic driver 1000 REM ee*.e* GRFXTEST.BAS ****** 2330 FOR I=1 TO 3 1010 GOSUB 99E0 : GOTD 1200 2340 FOR C=1 TO 10 1020 REM Sample POINT oPeratlon drover. 2350 X=INT(RND(0)*128) 1020 POKE(F7.F) REM Set function 4.5.6.7 1040 2360 V=INT(RND(0)*64) POKE(X6.X) : POKE(V6.V) REM Set POINT coords 2370 W=INT(RND(0)*100) 1050 CALL(67) REM Piot It 1060 RETURN 2380 H=INT(RND(0)w85) 2390 GOSUB 1140 1070 REM Sample LINE & RECTANGLE driver 2400 NEXT C 1080 POKE(F7.F) REM Function 0.1.2 8.9.10 12.13.14 2410 FOR 0=1 TO 500 : NEXT D 1090 POKE(X6.X1):POKE(V6.(1) REM Set start coords a 2420 POKE(F7.3) POKE(X6.0) : CALL(67) 1100 POKE(X7.X2):POKE(V7.V2) REM Set end coords 2430 NEXT I 1110 CALL(67) REM Draw it 1120 RETURN 2450 REM Use 'INVERT LINE' function to create MOire Fringe. 2460 F=10 1120 REM Sample ELLIPSE driver 2470 FOR I=1 TO 2 1140 POKE(F7.F) REM Set function 16.17.18 2480 X1=0 : V1=0 a X2=127 1150 POKE(X6.X) : POKE(V6.V) REM ElllPse Position 2490 FOR V2=0 TO 63 1160 POKE(X7.W) : POKE(V7.H) REM Ellipse dimensions 2500 GOSUB 1170 CALL(67) 1080 REM Draw it NEXT 1180 RETURN 2510 V2 2520 11=0 : YI=0 : V2=63 1200 PRINT " ee.ee. GRFXTEST.BRS ) a*e**'*e" PRINT 2530 FOR X2=126 TO 0 STEP -1 1210 PRINT " SAMPLE GRFXPAK DRIVER" : PRINT 2540 GOSUB 1080 1220 PRINT " Lines 1020-1180 give exa..IPles Of how to Pass" 2550 NEXT X2 1230 PRINT " Parameters to the graphic driver Package." 2560 X1=0 : V1=63 : V2=0 1240 PRINT " Normally. the function calls wOUld be Placed" 2570 FOR X2=0 TO 127 1250 PRINT " in -lane' .n a Program to increase speed." 2580 GOSUB 10E0 1260 FOR I=1 TO 4 PRINT : NEXT I 2590 NEXT X2 1300 REM Rotating screen clear using 'CLEAR LINE' function. 2600 11=0 : V1=63 : 12=127 1310 F=9 : : X1=0 : : 1'1=0 12=127 FOR V2=0 TO 63 2610 FOR V2=1 TO 63 1320 GOSUB 1060 2620 1330 NEXT V2 GOSUB 10E0 2630 NEXT V2 r 1340 F=9 a : X1=0 V1=0 V2=63 : FOR X2=126 TO 0 STEP -1 2640 NEXT I 1330 GOSUB 10E0 2660 REM Draw random 1360 NEXT X2 rectangles using 'INVERT RECTANGLE' 2670 F=14 1380 REM Set alternate Horiz. lines from top to bottom. 2680 FOR 1=1 TO 3 1390 F=8 : 11=0 : 12=127 FOR TO V1=63 0 STEP -2 2690 FOR R=I TO 10 1400 V2=Y1 : GOSUB 1080 2700 1410 NEXT VI X1=INT(RND(0)*128) 2710 1420 REM V1=INT(RND(0)*64) INVERT alt"ernate vent. lines from right to left. 2720 X2=XNT(RND(0)*128) 1430 : F=10 V1=0 : V2=63 FOR X1=127 TO 0 STEP -2 2731 Y2=INT(RND(0)*64) 1440 X2=11 : GOSUB 1080 2740 GOSUB 1080 1450 NEXT X1 2750 NEXT R 1460 FOR D=1 TO 500 : NEXT D FOR TO : 1480 REM Clear screen 2760 D=1 500 NEXT D 1490 2770 POKE(F7.3) : POKE(X6.0) : CALL(G7) POKE(F7.3) : POKE(X6.0) : CALL(G7) 2780 NEXT I 1510 REM Random horizontal & vertical lines. 2E00 REM Use 'INVERT WINDOW' function to draw random blocks. 1520 REM Do 1 horiz. 6 1 vent. line Per loop. 1530 Feb0 2810 F=2 2820 FOR I=1 4 1540 FOR I=1 TO 40 TO 2630 : 1550 X1=INT(RND(0)*128) POKE(F7.3) POKE(X6.0) a CALL(67) 1560 V1=INT(RND(0)*64) 2840 FOR R=1 TO 8 1570 X2=INT(RND(0)*128) 2850 X1=INT(RND(0)*128) 1580 V2=V1 2860 V1=INT(RND(0)*64) 2870 1590 GOSUB 1080 X2=INT(RND(0)+128) 1600 X1=INT(RND(0)*128) 2880 V2=INT(RND(0)*64) 1610 YI=INT(RND(0)*64) 2890 GOSUB 10880 1620 X2=XI 2900 NEXT R 1630 V2=INT(RND(0)x64) 2910 FOR D=1 TO 500 a NEXT D 2920 NEXT I 1640 GOSUB 1080 2940 REM Invert whole screen with 1650 NEXT I 'INV WINDOW' function. 2950 F=2 1660 FOR D=1 TO 500 : NEXT D 2960 X1=0 a V1=0 : a 16E0 REM Invert state of entere screen twice 12=127 Y2=63 1690 F=2 2970 GOSUB 1080 2980 FOR D=1 TO 500 : NEXT a D 1700 X1=0 V1=0 12=127 : V2=63 2990 : V1=63 : 1710 GOSUB 1080 X1=127 :"X2=0 V2=0 3000 GOSUB 1080 1720 FOR 0=1 TO 500 : NEXT D 3010 FOR 0=1 TO 500 : NEXT : D 1740 11=127 V1=63 a X2=0 : Y2=0 1750 GOSUB 1080 3020 REM 3030 FOR I=1 TO 6 : PRINT NEXT I 1790 REM Sceen clear. rotating from top corner. 3040 PRINT ' RANDOM POINT TEST" 1800 F=9 : X1=127 : Y1=63 a V2=0 : FOR 12=127 TO 0 STEP -1 1810 GOSUB 1080 3050 PRINT " This would be a good tome to make a cup of tea." 1820 NEXT X2 3060 PRINT 3070 PRINT " The display will show any pattern sens,t.v.tr .n' 1830 F=9 : X1=127 : V1=63 a X2=0 a FOR V2=1 TO 63 PRINT " 1840 GOSUB 10E0 3080 your BASIC random number generator function. .f" 1850 NEXT V2 3090 PRINT " left running for several minutes." 3100 PRINT 1880 REM Random angled lines. Joined end -to -end. 1890 F=8 3110 PRINT " This .s the last example. It is a 'near-.nf.n.te'" 1900 FOR I=1 TO 4 3120 PRINT " loop. Press 'BREW(' when you wish to stop." PRINT : 1910 FOR L=1 TO 3 2130 PRINT 3140 FOR D=1 TO 1000 : NEXT D 1920 XI=X2 : V1=V2 REM Avoid 1930 X2=INT(RND(0)*178) 3160 subrout.nes here to gain speed. 1940 V2=INT(RND(0)*64) 3170 POKE(F7.4) 3180 FOR 1=1 1950 GOSUB 1080 TO 1E4 1960 NEXT l 3190 POKE(X6. INT(RND(0)*128)) 3200 POKE(Y6. INT(RND(0)+£4)) 1970 FOR D=l TO 500 : NEXT D 3210 CALL(67) 1980 NEXT I NEXT I 2000 FOR D=1 TO 500 NEXT D 3220 3240 PRINT a 2020 REM Clear screen. 0 lines protected PRINT " My. we are patient. aren't we." 2250 END 2030 POKE(F7.3) POKE(X6.0) : CALL(G7) 3260 REM 2050 PRINT " This may be a good Opportune tr to ad,ust" 9980 REM Standard GRFXPAK Parameter nodule 2060 PRINT " the vert.Cal height and linearity Of your" Def.nat.on 9981 137=25600 REM grfxPap s/r entry 2070 PRINT " monster screen to give a ROUND circle." address 9982 F7=G7 3 REM grfx function code store 2080 FOR 1=1 TO 6 : PRINT : NEXT I 9983 X6=F7 1 REM 2110 REM Draw concentric circles about centre of screen X1 co-ordinate store 9984 V6=X6 1 REM VI " 2120 F=16 : X=64 V=32 9985 X7=V6 1 REM " 2140 FOR C-0 TO 11 12 9986 V7=X7 1 REM V2 2150 W=C*5 : H=W 2160 GOSUB 1140 9987 T7=V7 1 REM pixel test result store REM 2170 NEXT C 9988 Clear screen (text mode). Protect 0 lines 99E9 POKE(F7.3) : 2200 REM Draw another .:.role to produce Moore fringe POKE(X6.0) a CALL(67) : RETURN 2210 X=46 9990 REM 0. SET WINDOW (4)PARAMS 10. INVERT LINE (4) 2220 FOR Ce0 TO 15 9991 REM 1. CLEAR " (4) 11. - 2230 W=C*5 H=W 9992 REM 2. INVERT " (4) 12. SET RECTANGLE .4. 9993 REM 2240 GOSUB 1140 2. PROT/CLEAR Cl) 13. CLEAR " (4) 9994 REM 4. SET POINT 2250 NEXT C (2) 14. INVERT " ' (4) 2280 REM Clear screen 9995 REM 5. CLEAR " (2) 15. - 9996 REM 6. INVERT " (2) 16. (4) 2290 POKEF7.2) : POKE(X6.0) : CALL:G7) SET ELLIPSE REM 7. " 2310 REM Draw random Et I.P;es. 9997 TEST 12) 17. CLEAR (4) 2320 F=16 999E REM E. SET LINE .4) 18. INVERT (4) 9999 REM 9. CLEAR " .4) 19. - 42 - July 1983 ETI 6450 3F6534 'WINDOW BSTA.UN DIRTST WORK OUT STEPPING DIRECTIONS SOURCE LISTIÑG - 6460 OF0409 :WLOOP LODO. R3 INDEX FETCH INDEX TO POINT HANDLER POINT 6401685 graphic driver 6463 BF642B + BSXA FNTBLOC.R3 PLOT 6466 0D04DC LODA.R1 XPLOT RECOVER COORDS 6469 0E04DD LODA.R2 YPLOT 646C 0402 LODI.RO LCOM LOG. COMP. NO CAR GRFXPAK 646E 93 LPSL ONE OF SEVERAL GRFX OPERATIONS. PERFORMS 646F EE0407 COMA.R2 Y2 FINISHED VERT LINE VET? 6472 1805 BCTR.EO WXTST THE ACTUAL OP. PERFORMED IS SELECTED BY A CODE BYTE 6474 860591 ADDA.R2 YINCR NO. STEP VERTICALLY X CONT. INTO LOCATION TFUNCTN" BY THE CALLING PROGRAM. POKED 6477 1867 BCTR.UN WLOOP t FUNCTIONS -- 6479 ED0406 'WXTST COMA.RI X2 FINISHED WHOLE WINDOW? 647C 14 RETC.EO YES. RETURN TO CALLING PROGRAM. -- GENERAL SCREEN OPERATIONS 6470 800550 ADDA.R1 XINCR NO. MORE TO DO CORNERS (XI.VI) 4 (X2.Y2) t 00. SET WINDOW WITH OPP. 6480 0E0405 LODA.R2 Y1 RESET Y TO Y1 01. CLEAR WINDOW 6483 1B5B BCTR.UN WLOOP 02. INVERT WINDOW í. 03. SCROLL PROT. (X1) LINES. CLR SCREEN TO TEXT MODE Screen clear and protect 1w SINGLE POINT OPS-- 'PROTCT R0 X1 FETCH SCRL PROTECT VALUE SET (TURN ON) SCREEN POINT A 91.51 6485 000404 LODA. 04. 6488 440F ANDI.RO OF TRUNCATE ANY SILLY VALUES 05. CLEAR (TURN'OFF) " 6480 C8A8 STRR.R0 * PROT 06. INVERT (REVERSE) " " 07. TEST STATE OF SCRN POINT (X1.51) AND LEAVE A 00 H'20 SPACE CODE (IF BIT OFF) OR "FF" VALUE AT LOC. "BITVAL". 648C 0420 LODI.RO 648E 0700 LODI. R3 0 INDEX INT2 STRA.1,10 VDU. R3 CLEAR SCREEN LINE OPS-- 6490 CF7800 6493 CF7900 STRA.RO VDU.100.83 OR. DRAW (SET) A LINE FROM (X1.Y1) TO 6516 8604 ADDIR2 04 SET ATTR. POINTER HI BYTE 65C6 8869 ADDR.R2 YINCR IF Y2)V1 THEN INCR V BY 1 6518 CA46 STR11.82 ATTPNT IF V2Y1 IGNORE 651A 0402 - LODI.R0 02 CHUNKY GRFX BIT IF Y2(Y1 THEN DECR Y BY 1 651C C2 STRZ.R2 651D 411CI I ANDR.R2 *ATTPNT TEST IF GRFX ALREADY SET 63C8 0864 LODR.R3 DELTAX SET R.R.DX 651F 1907 BCTR.GT CONV2 65CA 8066 ADDR.R3 RUNCNT 65CC CB64 6521 CCB4E0 - STRA.RO .ATTPNT NO. SO SET IT NOW STRR.R3 RUNCNT 6524 20 EORZ.R0 AND ERASE ASCII CHAR 65CE 085F LODR.RO DELTAY DECIDE IF X IS TO BE CHANGED 6525 CCB4DE STRA.R0 *POINT 6500 A3 SUBZ.R3 RODV-R 6528 03 :CONV2 LODZ.R3 FETCH BITMAP 8 SET CC NON -ZERO 6501 E77F COMI.R3 7F If RUNCNT ) 127. do next 6529 17 RETC.UN 6503 195E BCTR.GT LLOOP2 632A 20 +CONv3 EORZ.R0 BAD COORDS. SET RO 8 CC00 6505 7502 CPSL LCOM 6520 17 RETC.UN 6507 E3 COMO,R3 IF R/DY-R THEN GOTO STEP LOA 6508 7702 PPSL LCOM 652C 01020498 'BTABL DATA 1,2.4.8 BIT -MASK TABLE 65D8 1957 BCTR.OT LLOOP2 6530 10204080 I DATA 10.28.40.80 63DC 8952 ADDR.R1 XINCR IF 02)81 THEN INCR XPLOT BY 1 IF 82.81 IGNORE Direction test subroutine I IF 02 633E AI - SUBZ. RI Determine DELTAX Rectangle function 653E 1808 BCTR,EO CALDX2 %2X1. XINCR-0 I 6541 1906 BCTR.GT CALDXI 82)51. XINCR..: I PLOTS A RECTANGLE USING COORDS (XI.Y1) l (X2.Y2) 6543 07FE I LODI.R3 -2 82(81. XINCR.-I to AS DIAGONALLY OPPOSITE CORNERS 6545 24FF s EORI.R0 OFF DELTA% Ive, make ,t cotillee 6547 8401 A00I.R0 1 63F1 3E6534 'RCTNGL BSTA.UN DIRTST Determine l.ne d,rectons 6549 8701 :CALDXI ADDI.R3 I 6548 CC05AE :CALDX2 STRA.R0 DELTA% Save ABS(DELTAX) E5F4 3827 :RECT1 BSTR.UN RPLOT Plot olxel at R1.R2 654E CF05B0 i STRA, R3 XINCR Save X stepping increment 65F6 8D05B0 I ADDA.RI XINCR NEXT x 65F9 600406 COMA.R1 X2 U. to start of next lane ret? 6551 0E0405 LODA.R2 VI Compare Y1 against Y2 65FC 9876 BCFR.EO RECTI No. seep 6554 000407 LODA.R0 Y2 l000ing. 6557 0700 LODI.R3 0 Prepare VINCR E5FE 3810 :RECT2 BSTR.UN RPLOT R1.1(2 6600 8E0501 - ADDA.R2 VINCR 6559 A2 NEXT V SUBZ.R2 Determine DELTAY 6603 EE0407 COMA.R2 Y2 More? 655A 1808 8 BCTR.EO CALDY2 V2.Y1. YINCR-0 6606 9876 I BCFR.ED RECT2 Yes. 655C 1906 BCTR.GT CALDYI Y2)Vl. YINCR.*1 635E 07FE LODI.R3 V2(Y1. -2 VINCR.-I 6608 3813 :RECT3 BSTR.UN RPLOT R2.Y2 6560 24FF EORI.R0 OFF DELTAY negative. make It Positive 660A 800580 I SUBA.RI XINCR NEXT X. STEP(-XINCR) 6562 8401 ADDI.R0 1 6600 ED0404 I COMA. R1 X1 More? 6564 8701 :CALDYI 1 ADDI. R3 6610 9876 BCFR.EO RECT3 6566 CCO511F 'CALDV2 STRA.R9 DELTAY Save ABS(DELTAY) 6569 CF05B1 t STRA.R3 YINCR Save V stepping Increment 6612 3809 :RECTO BSTR. UN RPLOT 81.81 656C 17 I RETC.UN 6614 860551 I SUBA. 82 YINCR NEXT V. STEP(-VINCR) 6617 EE0405 COMA.R2 VI Mors? Line function 6618 9876 BCFR.EO RECT4 1w 6EIC 17 RETC.UN Finished. return to caller. Plots straight In.. from (%í.Y1) to (X2.Y2) 661D 0E0409 +RPLOT LODA.R3 1 1.1*Mim0m % or V coordinate 127 INDEX P,eit up fonCt,on ,nee. 6620 0E6407 - 11.51R FNTBL-14.18' Offset Indies a co BSTR 6623 000400 I 6560 20 .LINE EORZ.R0 Clear slope prediction counter LOD8.R1 XPLOT P.c. PP coords 636E CC0582 STRA.R0 RUNCNT 6626 0E04D0 LODA.R2 YPLOT 6629 17 RETC. UN Return for nest Pont. 6571 3841 BSTR.UN DIRTST Set up DELTAX. DELTAY. %INCR. YINCR 6573 6839 DELTA% Determine COMR.R0 if none ) 45 degrees Ellipse and circle function 6575 106503 BCTA. OT LLOOP2 Yes. do LLOOP2 am I« 10 Slope muss be (. 45 degrees RI contains X1 centre CO -Ordinate i R2 Contains VI centre CO -ore, nate I. 6378 C932 :LLOOPI STRR.RI TEMPX SAVE POINTERS FOR LATER X2 conta.ns Hor,2 width/2 657A CASI STRR.R2 TEMPY w Y2 contains Vert he,sht/2 657C 0F0409 LODA.R3 INDEX PICK UP INDEX FOR POINT OP's. 657F 8E6413 BSXA FNTBL-0C.R3 JUMP TO HANDLER 662A 8D0406 ELIPSE ADDA.R1 X2 Add hors% width to R1 £620 CD06EC I STRA.RI FIRSTx Save Coor of f.rat oo,nt 65E2 0928 LOOR. R1 TEMPX RECOVER POINTERS 6630 CEOEED STRA.R2 FIRSTY 6584 01)27 LOOR. R2 TEMPY 6633 8E63E0 BSXA FNTBL-1('24'.53 and plot f,rst bo,nt 6636 20 6586 E00406 COMA. RI X2 IF XPLOT-X3 THEN END EORZ.R0 6509 1065E4 BCTA.EO ENDLIN 6637 070E LODI.R3 8 Iw 6639 CF46E4 :ELIP2 STRA.R0 CNTR.R3- In.t.el,se CNTR to 0.00 658C 8922 ADDR.RI 663C 3878 - BRNR.R3 ELIP2 XINCR IF 82)81. THEN INCR XPLOT BY 1 In.t SINE to 0.00 00 663E 0501 IF X2.91. IGNORE LODI.RI 1 10.1 COSINE to 1.00 00 6640 CD06E9 - STRA.R1 IF X2(81. THEN DECR XPLOT BY 1 COSINE 1* 658E OBIF LODR.R3 DELTAY SET R.R.DY MAIN LOOP STARTS HERE 6590 8820 ADDR.R3 RUNCNT . 6592 CB1E a STRR.R3 RUNCNT SINE . SINE COSINE/128 4. 6643 0006E9 :NEWSIN 6594 0818 LODR.RO DELTA% DECIDE IF VPLOT 15 TO BE CHANGED LODA.R1 COSINE Get Old C tne 6646 0E06EA : 6596 A3 I SUBZ.R3 LODA.R2 COSINE.' 6649 0F06EB I LODA.R3 6597 E77F COMI.R3 7F If runcnt ) 127. do nest COSINE.2 6599 1950 BCTR.GT LLOOPI 664C 3F66F0 I BSTA.UN SHR Calo cos/12E 6398 7502 CPSL LCOM 664F 8F06E8 6590 E3 COMZ.R3 IF R(DX-R THEN GOTO STEP 2 ADD4.R3 51NE*2 Add to sane 659E 7702 PPSL LCOM 6632 770£ PPSL WC 8E06E7 6540 1956 1 BCTR.GT LLOOPI 6654 ADDe.R2 SINE*1 1 6657 B006E6 ADDA.RI SINE 6582 8AOD 1 6654 CD06E6 STRA.R1 SINE new ADDR.R2 VINCR IF Y2)YI THEN INCR VPLOT BY 1 Save s.n. 663D CE0EE7 IF ).2.Y1. IGNORE STRA.R2 SINE.' 1. IF Y2(/1. THEN 66E0 CF06EE STRA.R3 SINE.2 I DECR YPLOT BY 1 6544 0BOC I LOOR. R3 UNCNT :" COSINE COSINE - SINE/128 6546 ÁB06 SUBR.R3 ELTAX SET R.R-OX 6662 3F66F0 'NEWCOS 6588 CBO8 - STRR.R3 UNCNT BSTA.uN SHR Ca lc san/12E 6500 1840 BCTR.UN LOOP: I. LOCAL VARIABLE USED IN LINE ROUTINE 6666 OCOEEB LODA.R0 COSINE*2 Subtract R123 from eos.ne 1. 6669 A3 - SUBZ.R3 65AC 00 .TEMP% DATA 6660 C3 - STRZ.R3 INTERMEDIATE X A V COORDS 6580 00 :TEMPY DATA £668 770E - PPSL NC 638E 00 :DELTA% DATA ABS(82-8I) 6660 OCO6EA I LODA.R0 COSINE.' 65AF 00 1DELTAV DATA ABS(Y2-Y1) 6670 A2 SUBZ.R2 6671 C2 6580 00 (XINCR DATA Hor,x. direction Ila. STRZ.R2 65BI 00 :VINCR 6672 0006E9 LODO. RO DATA Vert.cal ' COSINE 6675 Al I 6582 00 (RUNCNT DATA SLOPE PREDICTION COUNTER SUBZ. RI 6676 CI STRZ,RI 6677 CD0EE9 STRA.R1 COSINE 8123 It,. loop ee used ./ slope ) 43 Save as new cos.ne 667A CEOEEA STRA.R2 COSINE.' 6383 6670 CF06E8 STRA. RS C977 :LLOOP2 STRR.RI TEMPX SAVE POINTERS FOR LATER COSINE.2 6585 CA76 STRR. R2 TEMPY . MULTIPLY COSINE BY WIDTH 6587 0F0409 LODA.R3 INDEX GET INDEX TO BIT ROUTINE 000406 65BA BF6413 BSXA FNTBL-OC.R3 ADO IT 66E0 :COSBYW LODA.R0 82 mutt oath .n R0 br COS .n R1.2 6663 3FE707 1 BSTA.UN ILTPLY 1Returns RSLT .n R1.231 44 - July 1983 ETI R123 ter 128 '6686.8E0404 ADDA.R2 X1 Add centre X coord 66F0 0408 :SHR LODI,R0 WC Dlv,des by shifting 8123 right 7 bits 6689 113 LODZ.R3 Test fr.ct,ones portion 66F2 93 LPSL 6688 9802 BCFR.LT NORND D7 . rounding flag D3 RRL.R3 Set up CAR drum MSB R3 668C 8601 ADDI,R2 1 Round upwards 66F3 R2 668E CE06EE :NORND STRA. R2 NESTS New %Prot coord (tentative) 66F4 02 LODO. 66F5 C3 STRO,R3 Shift 1 byte to right I (pick un CAR) e. 66F6 D3 PALPO and back bit i. MULTIPLY SINE BY HEIGHT 66F7 01 LODO, RI 6691 ODOEE6 ISINBYH LODA.RI SINE Fetch sine .nto R12 66FE C2 STRZ.R2 PAL. R2 Put cid sien bit In CAR 6694 0E06E7 LODA.R2 SINE.1 66F9 D2 : Y2 Mult height in RO by SINE in R1.2 6697 000407 LODA. RO ,nto RI + ERRO. RO Perform s/sn-eytend-tnru 669A 3F6707 BSTA. UN MLTPLY (RSLT en 81.231 66FÁ 20 66FB Cl STRO.RI Asoome . number RRL. RO Test Old sign bit 669D 8E0405 SDDA.R2 Y1 Add centre Y coord S6FC DO CPSL 6680 03 LODO. A3 Test tractional portion 66FD 7508 RETO. EO Return if sign . 0 6681 9802 BCFR.LT NORND2 07 . rounding bit 66FE 14 WC e 6683 8601 ADD1.R2 01 07 1 05FF LODI. R1 -1 Number was negative 6685 CEO6EF :NORND2 BTRA. R2 NEXT,6700 17 RETC.UN 6702 NESTS new coord, same 6648 00066E :TSTSAM LODA.R1 Test If cat ion Sub -routine last Point plotted. IS Bit . e Bit Binary Multioil 66AB ED04DL e COMA.RI XPLOT as le 66ÁE 9805 + BCFR.EQ NOT9AM e. RO . OPRI Multiplier 668 0 660400 COMA.R2 YPLOT plot it 10 R1.2 OPR2 Multiplicand 6683 1814 + BCTR.EQ INCTR Same. Wont :. +OPR1 DATA 0 Input OPerand storage 6685 CD040C *NOTSAM STRA.R1 XPLOT Update old CoOrds 6703 00 6704 0000 :OPR2 DATA 0.0 6688 060400 e STRA. R2 YPLOT :MCNT DATA 8 Multloir loon Count 6688 E92F COMP. PI FIRSTS Test if s as start 6706 0E 66BD 9804 - BCFR.EQ NOTSM2 to avoid double operation MLTPLY PPSL WC 66BF EA2C COMR.R2 FIRSTY 6707 7708 6709 0878 STRR. RO OPAL Save OPR1 66C1 1806 e ACTA. EQ INCTR STRR.R1 OPR2 Save OPR2 66C3 0F 0409 :NOTSM2 LOOP. RS INDEX and plot new point 6708 C977 6700 CA76 STRR.R2 OPR2.1 6606 BF63FB : POSA FNT8L-H'24'. R3 EORZ.RO Clear result 66C9 0919 :INCTR LODR.R1 CNTR Fetch old loop counter value 670F 20 6710 CI STRZ.R1 0818 1 LODR.R2 CNTR.1 66CB STRZ.R2 DÁ02 BIRR.R2 $.4 Add 0.01 (HEX) to It 6711 C2 66CD STRZ.R3 66CF 0900 BIRR. RI 1.2 6712 C3 LODI.R0 8 Loop count 6601 C911 STRR.RI CNTR Save new 1000 count 6713 0408 6603 CAlO STRR.R2 CNT114.1 6715 7501 :MLOOP CPSL CPR end 6717 C860 STRR.RO MCNT Save 100P count 6605 7702 IENDTST PPSL LCOM Comoare !OOP count to value Right one b,t : LOOR. PO OPR1 Shirt OPR1 6607 6503 COMI.R1 03 of PI . 03.24 3F 6A 88 (HEX) 6719 0868 I RRR.PO 6609 1E6643 BCTA.LT NENSIN More to do. 6718 50 STAR. AX OPR1 Save it I Over -shot? 671C C865 66DC 1905 BCTR.OT DONE to be done 671E 20 EORZ.R0 Test If add test next D0 RRL.R0 SEDE E624 COMI.R2 H'24' MS Brte equal. 671F add 6720 1E04 BCTR.EQ MNOAD If CAR was 0. no 66E0 1E6643 : BCTA.LT NEWSIN More %0 do. to caller. 66E3 17 :DONE RE,IC.UN FINISHED. return RSLT 6722 8861 +1100 ADDR.R2 OPR2.1 Add OPR2 to 6724 895E ADDR,R1 OPR2 in Local storage for CifCle routine f.ght 6726 51 :MNOAD RRR,p1 Shift entire result 66E4 0000 :CNTR DATA 0.0 Loon counter'store by bit 6727 52 : RRR,R2 one 66E6 000000 :SINE DATA 0.0.0 Sine value store 6728 53 : RRR.113 66E9 010000 :COSINE DATA 1.0.0 Cos,ne score :FIRSTS DATA 0 First plot point store 66E0 00 6729 0858 LOOR. RO MCNT Fetch current looP Count :FIRSTS DATA 0 66ED 00 6728 F868 BDRR. RO MLOOP More to do? 66EE 00 :NE%T% DATA 0 Tentative new PlOt point :NEXTV DATA 66EF 00 0 6720 7509 CPSL IaCgCAR I. DIVIDE BY 128 SUB -ROUTINE 672F 17 RETC.UN Finished. 5100 Z80 System Cards CP/M3 USERS I DRCII. To K-NAR Computer Cards q Please send me product data sheets. The board for multi-user installations. i 1I (I enclose 4 stamps). 256K dynamic RAM card, bank select, fast 4 Mhz operation, on -board memory l I wish to order 1: i /11' prom, dip -switch selectable boundaries, 1 : My cheque/order form for Is enclosed .l}; [if arl bank mode allows up to 2 boards on bus, : hidden refresh, phantom disable. Please debit my Bankcard No Yf'J 4 Price ,, List $995. + Name OUR PRICE Address $795 I I SBC-800. 4 Mhz Z-80 CPU, ' Signature ports, software two serial RS232 Please include me on your new product mailing list.' programmable Baud rate gen, Centronics I I am mainly interested in systems for. ' parallel port, 22 prog. I O lines, real time clock O Hobby, O Industrial use, O Education, (battery backed), 2K CMOS RAM, power ' O Process control. O Business O Other. battery on reset/power fail detect, ffil MI Mil t- - tttt - tttt ft backed as standard, etc. List Price $495. OUR PRICE $395 FOC-II. Enhanced fl y disk controller, IB 3740 list compatible, operates 5" & Price i'i11rt, raffiti 8" and single/d. density $465. ,a' - drives, handles up to 4 OUR PRICE drives, runs multi -density P 0 Box 412. Dandenong 3175 Phone (03) 795 5858 CP/M2.2 & MP/M 2. $370 4uthonsed distnbutce of SME Systems products Vectored interrupt 'Pnces subject to change without rotce Ni pnces excluding operation optional. hnrinfign ' tax For retail prices add 20% All boards fully assembled and tested and backed by 90 -day guarantee ETI July 1983 - 45 ALL KITS LESS 10%. OFFER ENDS JULY 31, 1983 ROD IRVING ELECTRONICS IS YOUR No. 1 KIT SUPPLIER '(Offer does not extend to July 1983 Electronics Australia Kits) OVER 300 NOW SOLD STEREO ETI-733 , RADIOTELETYPE ,/ EA INVERTER INCLUDING S195 SIMULATOR L4 TRANSFORMER CONVERTER p, ;0...,.. 300 WATTS FOR THE ;,,,:ii; 1, EA APRIL 83 1.444.4 \ MICROBEE `.t ' ..:a STEREO / SIMULATOR $12 I ..., , $19.50 urr.rK,.. ` for PCB version. ETI April 1983 .--. --- Have your Computer print the latest news from the inter. nation shortwave news service. Just hook up this project P 6 P $10.00 Self-contained version will cost approx. $20 between your shortwave receivers audio output and the Anywhere MicroBee' s parallel port. A Simple bit software the (does not include plugpack supply). of does in Australia decoding. Can be hooked up to other computers too. P.O.A. JUNE EA 1982 ETI-335 PUSHBUTTON -PROGRAMMABLE WIPER CONTROLLER c'-11 PHOTON t z. 0 11.) 0 7 -SLOT i 'PROTON win. TORPEDO S100 ...,a¢+Ea81* GAME MOTHER T.r`be^e= EA September 81 BOARD . '04 Eli May 80 ETI March 1983 $28.00 No more fiddling with knobs and not getting the delay t , - . between wipes that you want - this windscreen wiper $24.50 . $90.00 controller is simply programmed' with two pushbuttons 0 to provide the wiping delay you need. 150W MOSFET POWER FUZZBOX $19.90 CYLON VOICE EA December 80 AMP $79.00 $19.95 Plus Transformer 543.50 J' Plus Heatsink Oolled, Tapped and Black Simple Fuzz Box for i electric guitars. The no fuss, no Anodised 942.50 f. nonsense Fuzz Box. Contused - So are we. Seriously though If you want with a sound a difference, build this A general purpose 150W Mosfet Power Amp Module. project and you can the It distort waveform. produces a Here's a high power, general purpose Power Amplifier sound which is buzzy (like politicians at election time). EA Module for guitar and PA applications employing rugged, February 81 reliable Mosfets in the output. ETI 499 March 82 Sound like Darth Vader SLIDE CROSS FADER $85.00 TV CRO ADAPTOR $38.50 VOICE CANCELLER EA November 81 Includes Plug Pack. EA August 80 VOCAL 10.000l,. uwu...s411,41..K..... I Pua. {... ..40. . 160.4 .-..,.,... 4.+ $22.50 1 }- R ' e r`\ { 1t a -.` -W A X J {a, IV coP ADAPTOR ..--,.i.....:. ,.o.. e...e .r..1a. '«a. Po f^1 :-"tt Ever wondered how your voice substituted for your favourite vocalists would sound, well now its possible! You can r y cancel out the lead vocal on almost any stereo record and Su« LKI r substitute your own voice or musical instrument. EA April 82 Oct 82 ETI ETI'S BRILLIANT NEW LOUD SPEAKER PROTECTOR DIRECT-CONN ECT COMPUTER MODEM ETI 455 March 80 Employs unique 'Corn tutated Filter' design overcoming virtually all the problems involved with c onventional modems. Super flexible unit facilita tes communications between computers over cables, the telephone network a nd radio links. Unit connects to a stand ard RS 232 interface and Is capable of both 1200/75 Baud and 300/300 Baud transmission and reception * Line switching; answer and dialing facilities on board. $32.50 EXCLUSIVES: * Plated through, double sided PCB * Complete set of IC Our Price sockets * Kit requires 8 5 IN914 Diodes for programming these are included * Ceralock resonator and matching balanced load capacitor used for long life and high accuracy * Telec om approved isolating transformer and Reed relays $169.00 included. 414.- Here is an DIGITAL ENG. ANALYSER DIGITAL inexpensive ELECTRONIC O l g i t a l $48.50 CAPACITANCE Capacitance DUMMY LOAD METER $47.50 Meter which w measures from $99.00 1 pF to 99.99uF h A,µLYSEA pOl(at RAW lust three ranges. ith this unit you can test It's simple to use power Supplies at currents -01. 141ft.KU . and features a big up to 15 Amps and . 141 LI r' j . display with can "sink" up to Watts 200 ^t 'SW ! Q automatic on a static test and you can .`. updating and modulate the load to decimal points. perform dynamic tests ETI a EA August 80 i 1 EA March 80 147 October 80 ,.y 4 - ROD IRVING ELECTRONICS YOUR MAIL ORDER SPECIALISTS welcome Here - _-...... General Enquiries:(03)-489 8131e,.,..425 HIGH .ST, NORTHCOTE,VIC1OBIA 3Q7Q___ MaIJ de0H,ot Line(3 1 1436`., ALL KITS LESS 10%. OFFER ENDS JULY 31, 1983 THIS MONTHS KITS FROM EA ET1-1631.3 LAB SUPPLY $47.50 X ú.. 900 s m4 . $42.50 $15ETI Ir r.n3-. ETI-688 Every digital workshop should Who' Fully variable 0-40 V current limited 0-5 A supply with both BIPOLAR have one! Can be used to voltage and current metering (two ranges : 0-0.5 A/0.5 A' PROM program the popular fusible - ETI-668 This employs a conventional series -pass regulator, not MICROBEE switchmode type with its attendant problems, but dissipat .. link PROMs like the 74S188/ EPROM PROGRAMMER rf OGAAiVIi1AER Simple, low cost programmer for the MicroBee can iS reduced by a unique relay switching system switching ETI June 1983 288, 82S23 and 82S123 etc. program 2716s, 2516s, 2732s and 2764s. between taps on the transformer secondary. P.O.A. ETI Feb 1983 EPROM PROGRAMMER DUAL TRACKING POWER SOUND TRIGGERED $43.00 r SUPPLY $83.50 FLASH $26.50 yemor This easy to build sound or light operated flash trigger has No need for a many feature. Micro with EA's ¿-' Catch those great Eprom ...9 spectacular and Programmer .' r humorous suitable for 1II\, - a a moments like that 2716/2758 rs time your mother- Eproms.+¡j a a a a 1 in-law slipped on With Textool ny. - -^ a va a a the moss covered Sockets r55.00 + ajá4 a patio and broke EA January 82 her neck. ETI 588 ! October 80 ELECTRONIC .<,..f31N ;. e e ~rnty r METRONOME ' "LE GONG" ; Built around positive and negative 3 -Terminal Regulators, :::: this versatile dual tracking Power supply can provide $16.90 .. voltages from ±1.3V to ±22V at currents up to 2A. In $14.95 addition, the Supply features a fixed +5V 0.9A output and is new Metronome r completely protected against short circuits, overloads and Great Circuit The "Le Gong" Doorbell with with low (less than thermal runaway. EA March 82 current drain those unmistakable chimes one milliamp) drives a ItMi*/ generated by the LSI. A must for and a Led LE GONG Loudspeaker the man who has everything! EA Indicator. EA January 82 VOICE OPERATED RELAY February 81 >~ $14.95 LED LEVEL METER 31/2 DIGIT LCD $27.00 CAPACITANCE Build a Led level Meter with METER simultaneous peak and average display plus 60dB unes dynamic range. This kit is Handy pocket size Digital Ideal for any application a Capacitance Meter, runs off EA's great new Voice Operated Relay can be used to requiring a wide dynamic 9V battery and measure 1 pF to control a tape recorder, as a VOX circuit for a transmitter, or range level display. ETI 458 in 19.99uF Just three ranges. to control a slide protector. EA April 82 June 81 EA March 82 $79.00 FUNCTIONGENERATOR $79.50 3 a DIGITAL THERMOMETER: LOTTO/POOL'S 4 31/2 DIGIT LCD MOOT Ors r SELECTOR 4 :,. 1 E, ,., f -I '-f, ,.r. - $22.50 $79.00 .oa+s .{ FVNCTHINGFNF.RAtCIR I You have to be in it to win it Ij of This Function Generator with digital readout produces Sine. .. Take the chance out winning the Pools as well as Triangle and Square waves over a frequency range from Measure temperatures from the great below 20Hz to above 160kHz with low distortion and good Lotto, and build below freezing point to around new Pools/Lotto Number boiling point. EA February 82 envelope stability. It has an inbuilt four -digit frequency for ease and accuracy of frequency setting. EA Selector. EA July 81 counter o April 82 LARGE SCREEN TV STORAGE LOW OHMS SOUNDBENDER CRO ADAPTER $119.00 METER L..1'' _,, ' $29.00 ` ln, e* -, 04,vM $34.50 How many times have you 1 . i S . " Multirneter when Have great fun creating cursed your your own recording effects you had to measure a low -value l. 44; a ,r with music and voice. The , ;I 1.",. s + resistance. Well alas, with the Sound Bender can receive "Low Ohms Meter" you can from Electric Guitar, For a low cost Storage CRO with Synchronised Display. solve those old problems and in Microphones, etc. ETI Flectronic Graticule, One -Shot Triggering and Optional fact measure resistance from February 82 Storage of up to four Screen Displays it can't be beaten. EA 100 Ohms down to 0.005 February 82 Ohms. ETI 158 November 81 ROD IRVIÑG ELECTRÓÑCS, 425 HIGH STREET, NORTHCOTE 3070. PHONE: GENERAL ENQUIRIES(03) 489 8131 MAIL ORDER (03) 481 1436 WE are a No.1 Kit Supplier IsAs designed by ETI $HEo PREAMPLIFIER SPECnk..ATIt7P1S SSA0\y equency response: Hi.. ._ab. npul: l5Hz-130 kHz, +0,-1 db Low-leveilnput - confor m$k. m0 to ilAA equalisation, 20.2 dB ices atortion: 1kHz <0.003% on all Inputs (limit of resolution on measuring equipment due to noise limitation). $239 S/N noise: High-level input, master full, with respect to 300 mV input signal at full output (1.2V): >92 dB flat >100 dB A -weighted. . _. .. -. ,s r MM input, master full, with respect . T T y.. 11 a.w i .,.. to full output (1.2V) at 5 mV Input, 50 I-. T e 7. T, 1 I.,.. - ..r - pt y? Pa ohm source resistance connected: >86 dB flat >92 dB A -weighted. MC input, master full, with respect to full output (12V) and 200 eV input qi . - .._-_-JN.. . .._ o signal: >71 dB flat >75 dB A -weighted. POWER AMPLIFIER Please note that the "Superb Quality" Heatsink for the power amp was designed and developed by Rod Irving Electronics and is being sup- plied to other kit suppliers. This product cost $1,200 to develop so that your amplifier kit would have a professional finish as well as sound. We also have a new range of rack mounting boxes which will be released soon. SPECIFICATIONS Power output: 100W RMS into 8 ohms( 2 55 V supply). Frequency response: 8 Hz to 20 kHz, +0-0.4 dB 2.8 -Hz to 65 kHz, +0-3 dB. NOTE: These figures are determined solely by passive filters. Input sensitivity: 1V RMS for 100W output. Hum: - 100dB below full output (flat). Noise: -116 dB below full output (flat, 20 kHz bandwidth). 2nd harmonic distortion: <0.001% at 1 kHz (0.0007% on prototypes) at 100 W output using a 256 V supply rated at 4 A continuous. <0.003% at 10 kHz and 100 W. 3rd harmonic distortion: <0.0003% for all frequencies less than 10 kHz and all powers below clipping. Total harmonic distortion: Determined by 2nd harmonic distortion (see above). $2943. Intermodulatlon distortion: <0.003% at 100 W.(50 Hz and 7 kHz mixed 4:1). price Slashed $279 Stability: Unconditional THIRD OCTAVE GRAPHIC EQUALIZER SPECIFICATIONS E.T.1 . Dec. 1982 Bands: 28 Bands from 31.5 Hz to 16 kHz , Noise: <0.008 mV, sliders at 0, gain at 01-102 dB), 20 kHz bandwidth is ' Distortion: 0.007% at 300 mV signal, sliders at 0, gain at 0; max. 0.01%, sliders at minimum. Frequency Response: 1 2 Hz -1 05 kHz, +0, -1 dB, all Controls flat ,,..:».7. i-4- Boost & Cut; 14 dB L...... ,. ,. . ,. , ...... 1 unit $189 MX -1200 MICROPHONE/AUDIO MIXER 2 units $359 ri ó 4i ó ó ó ,: ti 0 4] O Q p O O O O O + EXTRA FEATURES OF OUR KITS POWER AMPLIFIER . I I , _. ._ KIT PRICE 5299 P&P 58.00 - I - I r5 I% Metal Finn Res,sprs are used wine poss10k 99ti -I-ii-p-, a Preemie Cols are %cowed Akxnnjn case as per the riceek l artck kW-s AI camporerts are tap oat" U =- -_=_ ga - _- Over 200 Kits row fad We nave Own fns unit and 50 MO. weal needs 10 GO Imp 9 , 1 1 I ,`cLO° I . . 1 : : . eery kit _ ' ;. SUPER F114159 Free pane, supped wen every kit at rp 0 ri entra Cost to you II We are so contrdent a this ke teal we can rip* ale (1=1==,==_ assemble] am tester[ S0 that people wed 00 rot nave _Í=i=== r tie tee can app ecate de toast that 0145 alpkte puts wt the IS des on a paw pee bays Winery apprec r-1 weeps to after pia:~ only Sí25 ==ill_1_11=1i i __ 'MI parts avaelable sepaeately to, both luta This unit Matures: I2 microphone line inputs with penDas , treble, effect and told beck Control, len each Channel LED peak Indicators or each channel PREAMPL)FER 2 turntable inputs with crossrade and Indnldual output Controls master equaliser for bass. mldr tinge end treblle variable headphone output etc. etc. KIT PRICE 5259 P&P 58.00 compete with carrying case. 1% Metal Film Reslsers are suppled 14 metres a toe Capacdaice Swam are scped sPE CIFrC AT10NS: FADER 6 CONTROLLERS la bol sera Use at m3takes( _ INPUTS 12 awn. law. UM. R rem. LOG 2S% L»LsWnn.de ;MC.46001 15 2 Mane radar. sea. eonwn LOG IS?. English -Linn- Swncles are supplied ro sltsnnees as 22 den 12 12 FIB Vduna, 300 UN1 others soppy Prun0.S2 WSWSTEREO a 2 t 2mrt at fie le.le 300, LIN NOW 12 Effect Send. 300. LIN We nave Mt aro tested tun ow aro so kroe *tut r few., Rturn (Ruin 201NSON 1 1 Ellett Return, 300. LOG 15% need, 10 go ario "My kit L OUTPUTS 2 P11we; 300. LOO 15% . Specials Imponed black aroOised akmnlm knpp5 O0 SRO amen 1 Need Plenty 300; LOO I s% ''Pd . ERNCI 544410 0L FA Out 0 00215 Svc 5500 Aga, as wN the Mime amp we are amen% Des kit d mom phone Stow e10 00e00 ¡100.181 FREOUE NCI' RESPONSE 2020 sea A & T ar a pce *tech we oto not there a , Vdd%¡P EQUALISATION TOTAL HARMONIC CASTOR TIOEL La. Peeve Is ol. Man 0.1% comercial 051 evaded' that sounds as 81100 Sane Ba : Sa METERI2 a enamel d Vu Marrs Om delnery as the PA 15d0 07750 Pis M PEA« INOICATOn- 12 LED Pee. irecalon only 5425 ''0o.'y y Oast :.2de VOLTAGE 240 VAL s01le P MrwN /0a POWER CONSUMPTION 72.Ftts I1 DIMENSIONS. 520 wet. See 101.10e p0 mm Ompowd compere who ceryv%cawl ROD IRVING ELECTRONICS 2 BRANCHES; 425 High St. Northcote, Ph.: (03) 489 8131 48-50 A'Beckett St. Melb. Ph.: (03) 347 9251 Mail orders: P.O. Box 235 Northcote, Vic. 3070 .a. ti c . Z m d 2 e 7W The `pfs:Graph' package reviewed Ever tried to tackle the problem of producing a really flexible graph routine? Difficult isn't it? Well, this package should interest you - it runs on the Apple II and produces graphs to order from your own data. What's more, it's compatible with PFS and VisiCalc files! Jonathan Phillips AS ANYONE who has ever tried to produce a into or out of the main menu, the disk flexible all-purpose graph routine will know, was used. graphs wasn't meant to be easy - to para- Now this fact, coupled with the usual phrase a well known aphorism. protection against copying the disk, will give The first problem comes when you try to the whole system rather a limited life - work out what the scale is going to be. That's until the disk wears out, in fact. fairly easy. Then comes the problem of label- Graph Problems apart, the system works well ling the axes - and if you want to do it - it will produce three types of graph: line properly (i.e: with the vertical axis labelled graphs, bar charts and pie charts. using letters on their side), then that means Bar and line graphs can be generated a lot of fiddling. using up to four sets of data on the same axes, Then of course comes the question of how and bars and lines can be mixed on the same to show the line - just as a solid white line, set of axes. or with symbols to show the data points? Labelling of each line, bar and pie segment When your data starts to come in the form is clear and easy to follow - lines are of comparitive graphs - i.e: more than one labelled either by colour, or by a symbol at graph on the same set of axes - then you are each data point (depending on an option). in real trouble. Bars and pie segments are identified by The pfs:Graph package is the third in a shading or colour. series of packages designed for the business All of the graph examples that I fed into user - the sort of user who is not interested i Ii I the system resulted in neat, easy to read in staying up to three in the morning polishing graphs - in fact, it would be very difficult to software routines. What he wants is results produce results that were otherwise, using without headaches. 1 this system. ZIAi ITZiNG The 'mother' package, 'pfs:' itself, is a 'data By making a few simplifying assumptions aquisition' system - that is, it allows you to (e.g: that the first set of data on a graph using design forms on the screen and then fill them Recommended. The pfs:Graph' package is distributed colour will always be in red), the system in. Packages like this are becoming very by Imagineerng, 3/579 Harris St, Ultimo NSW 2007. allows you just enough choices to define what common these days, as people realise that (02)212-1411. you want the reader of the graph to get out of it, without burdening you with unnecessary computers are not only fun - they can work How it performs for their living, too. choices. is use and Now, pfs: allows you to generate 'files' of Starting up the pfs:Graph package is some- All in all, the package easy to we to information, and to add to and change that thing of an experience. The disk drive whirrs produces good results- and now come information at will - more, it allows an for what seems like rather a longtime, with the most important part of the whole deal, operator to do this sort of thing, integrating the head doing what sounds like a polka the manual. the system into an office environment. across the face of the disk. In a system which is designed for use by The second package produced by Software After a while, all that stops and the main 'business people, excellent documentation is Publishing Corporation (the publishers of menu is seen, giving you the option of a must. The pfs:Graph manual is very much the pfs: series) was 'pfs:Report' -a 'report retrieving/saving the graph, altering the up to scratch. generator' package, which allowed that data, altering the format of the graph or It is easy to read, easy to use for reference tour' of the same no -headaches business user to generate printing the results. and includes a short 'guided printouts formatted neatly without worrying Operating the menu is also rather an features of the package, along with 'mon key - how to start about the details of writing a program to experience - for some reason the programmer see, monkey -do' instructions of do so. has decided to break with convention, and the thing up. Cunningly, pfs:Report took its data from use CTRL -C (which, on most systems is used The package also comes with a disk full of the 'files' produced by the mother pfs: system to mean 'interrupt') at the end of each input. example graphs, so that the naive user can few ideas of what is possible. All in - pfs:Graph does the same thing, only So if (as I did on a number of occasions, get a instead of reports, it produces graphs. by mistake through long habit) you enter all, the publishers have done a very good job Note that pfs:Graph can also be used with- the menu selection followed by RETURN, of making sure that the documentation is out the mother system, entering data directly nothing happens! Worse still, going back to a up to standard. to produce a graph. 'normal. system after playing with pfs:Graph In summary - yes, a good product; The pfs:Graph package runs on an Apple II for some time results in several unnecessary especially for those with either the base p/s: (with disk drive, of course), and produces the reboots! system, or VisiCalc (the 'spreadsheet. which pfs:Graph is also graphs in colour on the screen. The package Another problem I noticed was that, in package with for those who are is also capable of interfacing with a variety of going from the main menu to the various compatible). Recommended profit, as well as for fun. printers and plotters for hard copy. other parts of the system, each time I went into computing for ETI July 1983 - 49 EPS 30M EPS 20M .----....._ ` - sii m.Ó1 _ i- ALINCO ELECTRONICS _ . - -. - Commercial DC - r. --1 Power SuppIesEPS 200 _- IDEAL FOR - Ham Shacks, Technical Schools, Universities, - S_: I. . Research Laboratories, Repair Workshops, Assembly Lines, etc. EPS 300 EPS-20M EPS-30M Specifications EPS-200 EPS-300 (With Meter) (With Meter) Input Voltage 240V 50Hz 240V 50Hz 240V 50Hz 240V 50Hz Output Voltage 13.8 Volts DC ± 0.3V 10- 16 Volts DC 13.8 Volts DC ± 0.3V 10- 16 Volts DC Output Current 20 AMPS DC (MAX) 20 AMPS DC (MAX) 30 AMPS DC (MAX) 30 MPS DC (MAX) Ripple Voltage 30mV P -P (Rated) 30m V P -P (Rated) 30mV P -P (Rated) 30mV P-P (Rated) Automatic Protection 20 AI't PS 20 AMPS 30 AMPS 30 AMPS Circuit @ PTY LTD, 167 RODEN ST, WEST MELBOURNE 3003 IM ARK PHONE (03) 329 5433 TELEX AA 37753 HITACHI Hitachi Promise You Quality and Reliability Hitachi Portable Oscilloscopes V-1050F DC-100MHz Quad-Trace Delayed Sweep V -650F DC -60MHz Dual -Trace Delayed Sweep V -353F DC-35MHz Dual -Trace Delayed Sweep V -203F 0C-20MHz Dual -Trace Delayed Sweep V-422 DC^40MHz Dual -Trace ,, V-222 DC^-20MHz Dual -Trace L 4 V-212 DC-20MHz Dual -Trace V -1050F V-422 V-21 1 DC-20MHz Single Hitachi Mini Portable Oscilloscopes El 1® V-509 DC-50MHz Dual -Trace Delayed Sweep ,:at : V-209 DC-20MHz Dual -Trace Hitachi Storage Oscilloscope 1' k4. 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HIGHEST QUALITY 220v AC,.82.75 J 0-240 20-0-20V 4 POLE CHANGEOVER, COMPLETE WITH PRICES SLASHED PRICE $15.00 2 Amps 32 x 6.3mm SOCKETS, 2 AMP CONTACTS 0-240 0-24V PRICE $7.50 1.25 Amps 115v AC COIL ONLY $ 3 EA FUSE L 0-240 Rl-24V 4 POLE CHANGEOVER, HEAVY DUTY. . 3 AG MICROS WITCH PRICE fí12.50 4.2 Amps 240v AC COIL. 10 AMP CONTACTS. VALUE AT... $ 4 .5 O INVBONANZA! FROM 25OVAC 1OA ELECTROLYTIC ONLY $1.50 SOLID Switches_ ALL 250v AC RATING 1-9 10+ CAPACITORS - 2 AMP SOLE C/O CONY. $1.50 $1.25 SAVE 10 AMP N.O./N.C. $2.00 $1.70 STATE FROM TWO CENTS! 15 AMP DBLE C/O CONT.$2.50 $2.10 rDPDT 4.7uF 100V PT...54 100uF 160v PT..20c Y l0 for 904 VARIOUS ACTUATING LEVERS AVAIL. 70% 10 uF 16v PC...24 220uF 16v PT -10i 'O a, Voltage 22 uF 63v PT...7r 220uF 63v PT..204 Input 3-320 Input Current 2mA 47 uF lOv PC...34. 330uF 35v PT..204 $ Voltage 7. Ó ELECTRO -MAGNETIC 47 uF 25v PT..104 470uF 10v PC..104 Isolation 2S00V 0 AC ADAPTORS MOUNTING 50 uF 100v PT..104 470uF 50v PT..404 CHASSIS model $6.50 EA. 100uF lOv PT. ..34 640uF 16V PT..15C ERI 5505-SJ 410 10+ COUNTERS 100uF 16v PC...44 1000uF 10v PT..301 BEST QUALITY FAMOUS MAKERS 25% REED SWITCH, WAY BELOW NORMAL COST! 24v DC RESETTABLE. COILS PANEL MOUNTING...87.95 $6.95 1-9 10+ 24v DC NON-RESETTABLE. OUTPUT V CURRENT WAS NOW 12v SUPER -MINI COIL.$1.20 81.00 PANEL MOUNTING...$4.95 $4.40 3, 4.5, 6 300n0 $9.50 $7.10 REED SWITCH 0.60 0.50 110v AC CHASSIS MTG..82.50 $2.20 6, 7.5, 9 300mA 88.90 86.65 6v MINI COIL $2.00 $1.75 220v AC CHASSIS MTG..84.95 $4.40 Offer 6, 9, 12 300mA $8.90 $6.65 12v MINI COIL $2.00 11.75 6, 9, 12 SOOmA $13.50 $10.05 15-30v DC OPEN TYPE..83.00 $2.55 REED SWITCH 81.10 0.95 All above either 5 or 6 digit readout. DC -DC CONVERTER: Input 120 24v MINI COIL $2.90 $2.45 . 9, 12 800n0 88.90 56.00 STACKABLE VALU PLUS 6, STD. REED SWITCH$1.15 $1.00 MODULES SAMPLE 3 INCH 24V 24v Dc. 2 SIZES. NEW ONLY AC or DC Connectors PANEL MOUNTING. BAG s12.50 SERIES Internal position ind- An interesting collection of samples, -runs and excess, ,DSUB -MINIATURE icator switch for remote manufacturer's over BILLS 1" ,% sensing, highest quality. which includes IC's, diodes, switches, 1-9 10+ resistors and capacitors, electros etc. $ 10+ 84.50EA, PRICED NORMAL COST! rj 9 PIN FEMALE SOCKET $1.95 $1.75 WAY BELOW Also plugs, sockets, coils, terminals, High quality English Chloride -Gent 24V 15 PIN FEMALE SOCKET $2.25 $1.95 SLIM -LINE MODEL WITH PCB PCB's, pots, relays, etc. WORTH 866.00. AC or DC at approx. 150mA Current, at $5.oø 25 PIN FEMALE SOCKET $3.50 $3.00 EDGE CONNECTOR OVER 100 INDIVIDUAL ITEMS- AND a RIDICULOUS PRICE! Ideal for alarms. warning indicators, doorbells etc. 37 PIN FEMALE SOCKET $4.55 $4.00 STANDARD SIZE, PCB EDGE WE GUARANTEE VALUE OR WE REFUND LOUD RING DESPITE THE SMALL SIZE! 50 PIN MALE PLUG.... $6.00 $5.25 CONNECTOR ($1.50) $(3.90 THE PURCHASE PRICE! PRE-PAK la WEST ST, Phone or mail order 569-9797 BANKCARD accepted electronics p/I LEWISHAM, NSW 24 If PHONE ORDER SERVICE TV MESSAGE MAKER/INVENTORY W.F. Kreykes, St Albans Vic. I initially designed this program in black and white but Seven lines will be displayed with an average of 14 A8 clear screen, leave cursor in present now I've learnt more about colour and programming letters, subject to a maximum of 119 letters/codes per position " techniques such as Machine Code Sub -Routines page/display, counting each code in tables A and B as A9 change back/foreground colour " (MCSRs). one. AA show? The program writes messages on a TV or monitor The code recorded in memory for cursor forward AB white screen and has four separate memories in which you can (key F) is recorded as one code for each time this key AC black record a full screen of writing and call it up at any time is held down, even though the cursor moves forward AD green with a two -key code. With the options I have listed It is more than one space. The cursor can move to a AE red possible to print a page over a page that is already on maximum of 16 spaces before the key will have to be AF blue display, for special effects. released but will stop short at the start of the next line. D move cursor down one line As well as writing four pages, there is also a stack in Four separate pages can be called up at any time. F move cursor forward until key is released, which you can record messages. The messages can The screen will be cleared first before a page is subject to a maximum of 16 advances and/or be put in the stack one after another and, after reset- displayed. the start of the next line. ting the stack to the start again, they can be displayed There can be an average of 60 lines in the Inventory. by pressing key B. The first message will be displayed More lines are possible if only parts of a line are used; AO and A7 colour the whole line that the cursor is and, if key B Is pressed again, the first message will be i.e: the message currently on message in will be AC and AF cleared and the second the stack BY set background colour And Not activated when displayed. so on. W.F. KREYKES clearing stack or screen. If you want to display a message for the second 1983 time, or a message further up in the stack, type in 'CD' Table 'C' - Commands/instructions not recorded. followed by its address, which you have to note when on three lines will only take up 24 codes + BB = 25 B show next message in stack (inventory), recording. codes; that's 17 less than the average of 14 per line, clear previous one The vowels, being most commonly used, have been but didn't include any colouring. C1-4 display selected page, clear whole screen assigned 11, 22, 33, 44, 55, i.e: A, E, I, O, U. There are Options: Less than a page or one extra full page. first several MCSRs starting at 0862 and all of them end in D4. Before calling some of these I have used the Chip 8 Axxx instruction to set register A of the 1802 to the Data at No page 1 page 2 pages 3 pages 5 pages 2x1 and 1 full required address. This method is slower but saves memory and so may not be suitable for those who 0662 and 0686 6100 6f 01 6102 6f03 6f05 6103 at 0930 have expanded the memory as the most significant 078A 6009 600a 600a 600b 600c 600a aa24 high four bits of register A could be any value (which is 078C 61e8 6160 61d8 6150 6140 61d8 at0932 not important in the previous case). Start of Other MCSRs manipulate the monitors Chip 8 vari- Inventory 09E8 0A60 OADB OB50 0C40 OADB aa60 able stack (0470-047F) so they communicate be- tween each other. The use of machine code was necessary to make For 2xrh pages, with a full 58 codes per yx page CC clear screen immediately, reset cursor to the program as short as possible and colour the whole (182), there is no provision to prevent recording over start of display screen or line in a shorter time than the Chip 8 equiva- page three, so be careful. CD go to address specified by next three key lent would do. To display a page over a page, change 0690 to 00tt. presses, and display message The MCSR shown in ETI April 1982 had to be If you want to clear the screen before displaying COO enforce safety lock which prevents modified so that the memory data pointed to by the another page use code A8 at the start of the page that recording SEXed register was replaced, after the OUT3 was requires the screen to be cleared first. This feature C01-4 record display into selected page performed, to its original value. creates special effects when used carefully. CF reset stack/inventory to start immediately, To prevent writing over page boundaries (not a If you only want to recolour the bottom three lines clear previous page as 00-FF) I had to place a maximum of letters/ using A9, change 175c at 0758 to 1760; this leaves the E erase last entry codes per page/display. I settled on a figure of 119, top four lines in their original colour. EE erase last line which will still leave room for the BB if you want to After recording into the stack, the address showing record what is on display. This should be sufficient and where the next message will be recorded will have to Note: any attempt to go over this limit will prove fruitless; no be removed by pressing any key. This will then return 1. Record all your messages into the stack at once. To harm can be done to the recorded pages. the cursor to the start of the display. record into the stack after the first few messages have You'll know when this limit has been reached as a Attempting to display a message in memory that been recorded and the stack has been reset, simply strange shape will be displayed after only the first key has not been recorded will bring up rubbish; you may bring up each message and when the message press, and a letter requires two. If this limit is reached have to restart the program. comes up that is previous to the one you want to you either have to record what's on the display, erase To change the screen colour to something other record over, clear the screen (CC) and then you can the last entry/line or clear the screen before you dis- than white, change the value of VO at 075A to 60aX; X record your message. Remember that recording into a play any more messages. is the colours' code 0-7. To have different colour com- page resets the stack to the start again, so be careful. The display can still be recorded even though this binations when using A9, experiment with the value 2. Don't forget to colour the lines and backgrouna as sign has come up. The strange shape will not be added or deducted from VO at 0757, or replace it with these will not change colour until instructed. recorded as a BB is placed over it automatically. 00ff. 3. Code A8 should be used with care. Any invalid command will be greeted with a long 4. Don't record into the stack if the address shown beep. Table 'B' - These codes are ecorded as for Table after a recording is over FFF, e.g: 014. In this case you Once you've got the program up and running, re- will have to see if the whole of the previous message cord from 0600 to 0970. If you are planning to de- 94 used to signal inventory to reset to the start recorded has been able to fit in. monstrate it, record all your messages and check (endless loop) 5. You can display a page and then record it into the them to see that they are what you wanted. Before AO black stack but you cannot display the stack to record into a recording press C00, then after reloading into the Al red page. computer it will not be possible to accidentally record a A2 blue 6. The first message recorded into the stack will be message. Don't forget the colouring. Then record on A3 violet recorded at BC8. After each recording an address will another tape from 0600 to OFFF. When you want to A4 green be shown at the top of the screen; this is the address demonstrate your program you reload the computer, A5 yellow that the next message will be recorded at. If you note all your messages are set, and you can recall them as A6 p. blue these as with a tape recorder you'll be able to recall required. A7 white them with the CD command later. 52 - July 1983 ETI 660 SOFTWARE TV MESSAGE MAKER/INVENTORY TABLE 'A' MEMORY DISPLAY UTILITY 0600 086e 6caf 275a 278a 26a0 6200 6b00 83b0 1t L. Chubb, Kingsford NSW 0610 6100 a8fa d121 í40a d121 440b 179e 440c 77 0620 1670 440e 1816 4377 18c4 8444 8444 8444 I wrote this program because I was tired of debugging 0630 8444 8040 44d0 1640 4410 18c0 ff0a 8014 38 programs that didn't work, looking for errors byte by 0640 2644 1612 4100 8b30 a404 f355 a96e 131e byte. It also makes finding typing mistakes a lot easier. 0650 1055 26ce 00ee í60a 6d It's useful for those people who like to develop their 3410 3377 7301 4600 own programs as it sits high in memory, out of the way 0660 1766 6104 8f65 4101 16a6 6040 1018 1612 22 of other programs (location OF00) until it is needed. 0670 f60a 460c 1608 460d 183a 460b 16a6 4 600 To use this utility replace the first instruction of your' 26 0680 165c 460f 2786 6104 8165 3101 16sí 277c program with IFOO, then run it. 0690 2675 aXXX 131e 1065 17a6 2644 It will display eight Instructions at a time with the 40bb 1692 73 address next to each one, up to 512 bytes above the 06A0 00e0 6d16 00ee 60bb a96e 131e 1055' 360b memory 14 base address. The program initially displays 06B0 182c a96e 087d 0862 26a0 1029 ddf5 7d06 locations from 0600 to 07FF. 06C0 f 129 ddf5 7d06 1229 ddf5 f00a 1608 659f 33 Key F will display eight Instructions from the base 06D0 8505 3100 1716 6510 8502 3510 16e8 2730 address (at first the base address is 0600). Key D will 85 display the next eight instructions on from the ones 06E0 4010 00ee 7011 16de 40a9 1744 40ab 175a currently displayed. Key 5 will display the previous 06F0 40d0 1856 40aa 185c 40a8 1744 65aí 8052 7c eight Instructions. Key C will allow the base address to be changed. To do this press key C, the screen will go 0700 65ac 8502 35ac 17d4 90c0 00ee 08 bd 7c01 29 blank, then press a key between 0 and F. That will then 0710 4cb0 6cac 1708 a8d0 f01e d125 6710 8702 be the new base address. 96 0720 6559 8575 3100 172e 7101 4790 7101 7102 If you press any other key the screen will go blank; 0730 7102 6f3d 8115 3100 00ee 7207 4231 6200 80 press any correct key to bring back the display. 0740 6100 00ee 4dee 00ee 30a9 16a0 7c01 4cb0 44 MEMORY DISPLAY UTILITY 0750 6cac 08bd 80c0 70fd 175c 60a7 ac88 089f 0760 ad68 0891 00ee 606a a67d 1055 a681 1055 50 OF00 6E10 1F0A F50A OOEO 0770 166a a92c 8664 161e 1165 00ee 2772 a692 OF08 450F 2F1A 450D 2F26 68 OF10 4505 2F20 450C 2F7A 0780 6300 f155 173e 3d16 2792 600b 61c8 a400 OF18 1F04 6700 2F26 00EE 0790 1782 a402 1165 a400 6dee 27b0 16a2 3d16 8a OF20 87E5 2F26 00EE 6B00 07A0 2792 6daa 27ac 613f 622f 1612 a400 1165 OF28 6A00 4B30 00EE 2F34 48 07BO 2782 a470 088f 4094 178a 40bb 00ee 26ce OF30 7B06 1F28 6F00 8070 4F01 7901 17b2 83b0 OF38 8074 6906 0700 6100 9830 160e a96e 131e 1065 32 OF40 F929 DABS 7A06 2F5C 07D0 2654 17c6 ac88 4207 acb8 420e acf8 4215 F71E 55 OF48 7A08 A600 F71E 07E0 ad28 421c ad68 4223 ad98 422a add8 08a3 OF50 F165 7701 2F5C 8010 07F0 00ee 4100 180e 7001 d121 2730 a8fa d121 90 OF58 2F5C 00EE 8200 63F0 OF60 8232 6300 82E5 7301 0800 7101 3f3f 1800 4011 180e efal 17f2 73ff 99 OF68 3200 1F64 F329 DABS 0810 264c a8fa 1616 9b30 1612 8830 a404 f365 OF70 7A06 F029 DABS 7A06 0820 92 OF78 00EE FOOA AF3B F055 9830 17c2 26ce a404 1365 1612 2772 a400 OF80 0830 1155 a96e 087d 278a 1606 f90a fe0a 8ee4 18 0840 8ee4 8ee4 8ee4 f00a 8e04 2786 8090 81e0 59 0850 a400 1155 17a2 340e 173a 00ee a8ca d126 0860 172c 1872 a78e 5727 f6f6 f6f6 3099 1839 aa 0870 a7e7 f82c 2718 2057 62e2 d4f8 00a7 5762 00. 0880 47be 07ae ee4a 5ef8 bbf7 le3a 8530 9818 0890 00a7 47be 07ae 4e5a 8e57 279e 57e2 d4f8 03 08A0 c030 f870 a707 fa07 bfea foae a5f8 20af Ob 08B0 9f5a 632a 8e5a 602f 8f3a aee2 d4e9 61d4 08C0 2644 17fa 6094 1018 1640 1090 3020 0020 . 07 0080 08D0 4040 0000 00e0 0000 4000 4000 0000 2 4c 08E0 00e0 a0e0 a0a0 e0a0 a0a0 e040 4000 e020 08F0 e020 e080 e080 e080 c080 8080 a0e0 2020 0 44 0900 2020 e040 4040 4040 e080 8080 e080 e0a0 1 33 2 20 0910 e0a0 e020 e0a0 a0a0 e080 e020 e0a0 e000 le 0920 e0a0 e080 80a0 a0a0 2040 80e0 3 a0e0 a9e8 2a 0930 aa60 aad8 ab50 abc8 f090 90b0 10e0 9090 4 0940 90e0 e010 80b0 9010 5070 5010 90a0 c0a0 5 48 0950 90d0 b090 9070 2020 a0e0 1090 f0a0 9000 6 3c 0960 8888 8850 2050 88d8 a888 88a8 a850 7 2d 8 3e Axxx 0692 set by routine at 077C 40 Data underlined altered by instruction C.O.O. 9 ETI July 1983 - 53 te- S100 PRODUCTS Australian Designed and Manufactured:----. S100 Floppy Disc Controller S100 CPU Card . LINr.1N.A1M11º1. .11Jt ...:. . ii 1H 1EHNL0cr p1tODw5 AND E1tyEfosel cB . ; G-. . i B 71. i_ 1 lliparesew -J9 lnfttlla tituuI,lDJuu11n11L - - GENERAL DESCRIPTION: GENERAL DESCRIPTION: a large due to the presence of the The extensive capabilities of the rasefdc are to part * Z80A CPU running at a full 4 MHz Western Digital WD1795 double density controller chip. This device will perform the * Battery backed real time clock and Calendar majority of the timing and control functions as required by floppy disk drives when * 2K of CMOS ram as standard carrying out the following operations: * 2716/2732 Eprom from 2K to 16K 1. Head loading and unloading. * Z80A CTC with all 4 Channels available to user 2. Track seeking. * 2 -RS232 serial ports available 3. Address reading and writing. * Software controlled baud rates one each channel 4. Data conversion during read and write. * 16 -baud rates from 50-192200 baud available 5. IBM3740 soft sector compatibility. * 3.8 bit parallel ports via an 8255A 6. CRC error code inspection/generation. * Centronics compatible printer port via 8255A 7. Double density write precompensatlon. * DMA operations supported The board uses the phase locked loop technique when recovering data from disk, the * Power on lump to any 4K boundary In memory vco of the phase locked loop is under the control of the W D1691 circuit to ensure very * On board memory enable/disable for lull 64K operation reliable data recovery during double density operations. To ensure syncronism * Vectored interrupt chain via 280 CTC between the CPU and the controller Card dunng disk read and write operations the * Daisy chain Interrupts through system full supported raseldc will insert wait states until the WD1795 is ready to pass or receive the next * Comprehensive 2K monitor available byte of data. * Complemented by Disk, Memory and Input/output cards When used with rase80 CPU card the rasefdc card is available with full software * Local software and hardware support available support in the form of an eprom that is designed to interface with the rase80 monitor * A QUALITY AUSTRALIAN PRODUCT for console message passing. As well as the double density raw bios on the eprom there is a full disk diagnostic routine that permits the following operations to be Bare Board $180 & tax carried out: 1. Head seek testing. Kit Price 5350 & tax 2. Sequential sector write/read testing with random data. Assembled & Tested 5395 & tax 3. Read testing for CRC and seek errors. 4. Random sector write/read testing with random data. Manual Available Separately for S15 inc. Postage. 5. Multi drive random write/read testing. 6. Disk formatting (any type of disk). implementation the above tests, any errors that may occur are fully reported What's Coming During of _ back to the console for operator action. When using either CP/M or MP/M the rasefdc and rase80 CPU card are fully * 256K Dynamic Ram Card (S100) supported with boot. bios and xbios routines that will ensure a very smooth transition into the use of the above systems. Under normal circumstances the board operates * Intelligent Video Card (S100) within a polled environment, however when using interrupt based disk operating systems there are provisions for jumpering the necessary interrupt onto the S100 * Versatile I/O Card (S100) bus. * Hard Disc Controller Bare Board $150 & tax "Magnetic Kit Price $295 & tax Media Experts" Assembled & Tested $350 & tax We stock a very comprehensive range of diskettes Manual Available Separately for $12 inc. Postage Verbatim Discs 51/a"SOFT SECTORED -S- side double density $30.00/10 The Mitsubishi range of disc drives -D- side double density $47.50/10 M2896-63 8" SOFT SECTORED Slimline 8' Disk Drive, Double Sided, Double Density. No AC power required. 3ms track to track, 1.8 mbytes unformatted. 77 track/side, 10' bit soft error rate. -S- side single density $32.00/10 5495 + tax. Box 8 Power supply to suit 595 + tax -D- side double density 549.00/10 M2894 Standard size 8' drive, Double sides, double density, 3ms track to track access, 77 Please write or call for full floppy disc price list. track/side. 109 bit soft error rate. 5495 + tax. Box 8 power supply 595 + tax Well Known Brand M4854 Slimline 51/4" disk drive, Double sides, double density. 96 track/inch. 962t bitsfinch. 1.6 mbytes unformatted. 3ms track to track access, 77 track/side. 12 month data guarantee 5395 + tax. Box 8 power supply 565 + tax M4853 51/4 SS.DD. Slimline 514" disk drive. Double sides, double density. 1 mybyte unformatted. 3ms for 10 track to track, 80 track/side. 5922 bits/inch. steel band drive system. for only $29.00 5375 + tax. Box 8 power supply 565 + tax plus tax Available from: Ritronics Wholesale Pty. Ltd. 48-50 A'Beckett St. Melbourne 3000 (03) 347 9251 425 High St. Northcote Vic. (03) 489 7099 I Mail orders to P.O. Box 235 Northcote 3070 Vic. I at the 5-100 AND STD BUS CARDS- PARTS leading COMPUTERS AUSTRALIA'S IEEE -696 S100 SPECIALISTS COMPLETE SYSTEMS OR ALL THE PARTS YOU NEED TO BUILD OR ed:e EXTEND YOUR OWN! We supply products from:- CMOS SINGLE CHIP 1200 BAUD MODEM AEDGODBOUT MORROW SSM (U.K.) The FX409 from C.M.L. is hailed as the first such device QT JADE PULSAR to conform to the European mobile radio data link standard. WARNER This 22 pin part operates in full duplex and its low power S100 & STD consumption makes it suitable for hand held radio PRODUCTS:- communicators. CPU MEMORY ECONOMY I/O 5V EEROM VIDEO BUS CARDS (U.S.A.) General Instrument has dubbed its 128 x 8 EEROM "a DISK challenge to the dip switch". At around $5.60 in OEM quantities, CONTROLLERS they could be right. G.I. predicts we will see them in diallers, CUSTOM DESIGNS terminals, locks, traffic lights, keyboards ... the list goes on. ETC ETC ETC ETC ALSO: CABINETS POWER SUPPLIES SHARP 5KV OPIOS GET NOD FROM TELECOM CABLES CONNECTORS (MELBOURNE) Approval No RA83/107 is good news for opto users and even better news for former Fairchild fans. Sharp has Complete Systems:- published a handy cross reference to cover the gaps left when PULSAED COMPUTER the big 'F' quit the coupler game. Based on STD BUS UNIVERSE: The most advanced S100 WINCHESTER CONTROLLER SPORTS SASI BUS System in the world. Send an A4 stamped (U.S.A.) Western Digital Corporation are also building their addressed envelope for brilliant WD1002 Winchester/Floppy controller with ®Multibus free catalogue or indicate and STD interfaces. At around $388 for SASI and $950 for particular interest for Multibus, engineers will save heaps on development dollars. further details. daneva australia pty ltd 66 Bay Rd, Sandringham, Vic., 3191. A[OUSnt eUCleOeiC OerttOorprlS ri1 ttn P.O. Box 114, Sandringham, Vic., 3191. Telephone: 598-5622. Telex: ÁA34439. daneva MICROCOMPUTER Sydney: (02) E & M Electronics 51-5880 Adelaide: (08) DC Electronics 223-6946 PRODUCTS Perth: (09) Micro Controls 445-2544 130 Military Road. Guildford, NSW 2161 Brisbane: (07) Baltec 369-5900 ®Multibus Is a registered trademark of Intel Corporation. Tel: (02) 681 4966 Tlx: AA70664 Open 9-6 Mon to Sat. ETI July 1983 - 55 USING YOUR MICROBEE AS AN AUDIO FREQUENCY ADDR CODE LINE LABEL MNEM OPERAND COUNTER 00180 IMICROBEE AUDIO FREQUENCY COUNTER Tan M0446í 00110 1 .- 00120 Drive, Fern Tree 0400 00130 DEFR 16 Tom Moffat, 39 Pillinger 0400 00148 ORO 0400 Tasmania 7101 0400 002780 08150 CALL 8027 1LORES INT 00160 00170 :Get ereauency count Into HL. 00180 0403 118569 00190 STARTI LD DE,6985 ;TIME FOR COUNT e4e6 210000 00200 LD HL,O 'NUMBER OF CYCLES 0409 0802 00210 START IN 0,(2) 'BEGIN COL.NT How many times have you said, "Oh, how I wish I had 0408 88 0(1220 CP 8 ISE- CARRY IF NEW CYCLE a frequency counterf' But most people couldn't justify 040C 010000 00230 LD BC.8 the cost of several hundred dollars just for the occa- 040F C811 00240 RL :SHIFT IN CARRY, WANE BC-I OR 0 0411 09 '00250 ADD HL, 8C sional use. 0412 47 00260 LD 8.0 ;SAVE PREVIOUS STATE But if you load this program into your Microbee you'll 0413 lB 00270 DEC DE %COUNT DOWN TIME DELAY 8.0 to 12 kHz or so, 0414 7A 00280 LD be able to measure audio tones up 0415 83 0029e OR E with the frequency displayed in nice big characters on 0416 20F1 00300 JR NZ.STARTIEND COUNT IF ZERO 00310 your television screen. 00320 'Display the result. What can you use it for? Are you building the ETI- 00330 905 polyphonic organ? You'll need a frequency 0418 CD3E04 00340 CALL CLS ICLEAR SCREEN 0418 1110F3 00350 LD DE,BF3101SCREEN LOCATION counter to set it up. A computer modem? An RTTY 041E 011027 00360 LD 8C.2710 1100000 modulator? Testing your stereo? A frequency counter 0421 CD4F04 00379 CALL CON@ 0424 01E803 00380 LD BC.03E8 110000 is almost essential for all of these projects. 0427 CD4F04 00390 CALL CONv Now for some details of how it works ...The fre- 042A 016400 00400 LO BC.64 ;1000 Microbee's 042D CD4F04 00410 CALL CONY quency to be measured is fed into the 0430 010A00 00420 LD BC.BAN 110D cassette pon via the interface shown in Figure 3. You 0433 CD4F04 00430 CALL CONv the plug that normally goes to the 'earphone' 0436 010100 00440 LD BC.1 IIO insert 0439 CD4F04 00450 CALL CON) socket into the interface socket instead. The tone is 043C 18C5 00460 JR START! applied at the other end. Perhaps some enterprising 0047e 00480 ;Clear the screen rout,ne. manufacturer will offer the interface as a kit. 00490 Within the Microbee is an IC amplifier/protection 043E 010004 00500 CLS LD 8C.40e 0441 E5 00510 PUSH HL circuit that squares up the signal and presents it to bit 0 0442 2100F0 00520 LD NL.0F000 of data port 2. The program inputs the contents of the 8445 3620 00530 FILL LD (HL).20 with the result of the previous 0447 23 08540 INC HL port and compares it 0448 08 00550 DEC BC input. If bit 0 went low the carry flag is set. The carry 0449 78 00560 LD A,8 flag, regardless of its state, is rotated into the 1' posi- 044m 81 60570 OR C 0448 20F8 00580 JR NZ,FILL tion of the BC register, which is then added to HL, the 044D El 00590 POP HL frequency count. So HL increments for each cycle. 044E C9 00600 PET 00610 Meanwhile register DE has been loaded with a number that takes precisely one second to count down to zero. Each time the port is tested, DE is binary number that is the number of audio cycles that 'successive subtract' division routine. Then the whole decremented as well. When DE runs out of steam and occurred in one second. The binary number is con- procedure repeats. the program exits the loop, the HL register contains a verted to decimal and displayed on the screen by a The characters that appear on the screen are spe- cially constructed from graphics characters available in the Microbee, although not widely known about. They're produced after you call the 'LOPES' initialise ONE WIRE subroutine. You then write characters to the screen with bit 7 set high. There are six pixels in each graphics character, and 1' 12 graphics characters are used for each numeral, giving 72 pixels for each character. Figure 1 shows how an '8' is formed from the 12 graphics characters. Figure 2 shows how the data is developed for each graphics character. The resulting numerals stand 35 mm high on a 300 mm (12 inch) TV monitor; they're bigger than any LEDs you'll find on a'proper' frequency counter. For what it's worth, this 'graphics character' busi- 15 = DON'T CARE ANOTHER WIRE ness will work on a TRS-80 as well. 7 = 1 The accuracy of the Microbee as a frequency D[ counter is excellent, with the timebase being derived Figure 1. A complete numeral. Figure 2. Graphics character format. Figure 3. The interface. from the Microbee's t2 MHz crystal. The quantity for register DE in line 190 has been calibrated against a you -beauty' super accurate Systron Donner counter, and should hold for all Microbees if the 4 MHz crystals are any good. TO TAPE Sensitivity is also quite good, about 100 mV peak - EARPHONE to -peak at 1 kHz. At 10 kHz, it's 200 mV and at 5 Hz, 800 mV (that 100n capacitor is obviously getting in the 10k 100n way at such a low frequency). The program has been wnnen, by the way. so you can use the 'clear screen' and 'big number' proce- dures in your own programs. They've been presented as separate subroutines. All in all, it s not a bad little frequency counter, even though it's limited to audio frequencies. 2 If you don't feel like wrestling with all that nasty machine code. the usual offer applies: twelve dollars to the author brings the program on a cassette which Figure 4. The Microbee s cassette input circuit. can be loaded under BASIC, and an instruction sheet. all post paid. 56 - July 1983 ETI MICROBEE COLUMN AODF CODE LINE LABEL m4EN OPERAND MOOR CODE LINE LABEL rNEN OPERAND 00620 IConnert dlo;t to decimal and .how ;t. 00630 0490 8E83 044F 3EFF 00640 CONY LD A.BFFH A FOP COUNT 01140 THREE DEFW 838EH 'CLEAR 049F 834F 0451 3C 00650 CONV1 .INC A 01158 DEFW 08F83 0452 A7 00660 AND A 0441 8088 01160 DEFW 8880 0453 ED42. 00670 SBC HL.BC 0443 8C137 01170 DEFW 0878CH 0455 30FÁ 00680 JP NC,CONV1 0445 AC80 01180 DEFw BBOACH 0457 09 00690 ADD HL.BC 0447 B09E 01190 DEFW 9Eb0 0449 0458 87 00700 ADD A.A :X2 8040 01200 FOUR DEFW 04080 0448 9586 0459 87 00710 ADD A.A ;X4 8695 01210 DEFW 0454 4F 00720 LD C.A 04AD 8881 01220 DEFw 08188 044F 0458 87 00730 ADD A.A iX8 8085 01230 DEFW 08580 0481 045C 91 00740 ADD A.0 ;X12 8080 01240 DEFW 8080 0450 0600 00750 LD 8.0 0483 8095 01250 DEFW 9580 045F 4F 08760 LD C.A 0485 9783 01260 FIVE DEFW 8397 0460 ES 00770 PUSH HL 0487 8381 01270 DEFW 8183 0461 217904 00780 LD HL,ZERO 04139 8083 01280 DEFW 8380H 0.64 09 00790 ADD HL.BC ;HL POINTS TO NLMBER 0488 83AC 01290 DEFW 04C83 0465 0603 00800 l0 8,3 13 LINES OF CWVRACTERS 0480 4480 01300 DEFW 08044 0467 CS 00810 SHOW PUSH BC 048F 8086 01310 DEFW 8680 0468 010400 00820 LD BC.4 ;4 ROWS OF CHARACTERS 04C1 409E 01320 51X DEFw 9E4e 0468 ED80 00830 LOIR 04C3 8380 01330 DEFW 8083 0460 78 00840 LD A.E 04C5 878C 01340 DEFW BCB: 046E Co3C 00850 ADD A.3CH 04C7 8C80 01350 DEFW 0808CH 0470 SF 08860 LD E.A 04C9 AD80 01360 DEFW 080..00 0471 CI 00870 POP BC 04CB B08E 01370 DEFW 8E80 0472 10F3 00880 0302 SHOW 04CD 8783 01380 SEVEN DEFw 8387 0474 C647 00890 ADD 4,47 *POINT TO NEXT SCREEN LOC'N 04CF 839B 01390 DEFIa º883 8476 5F 00900 LD E.A 0401 8040 01400 DEFW 0«080 0477 El 00910 POP HL 0403 8e80 01410 DEFW 8086 0478 CO 00920 RET 0405 8044 01420 DEFW 04480 00930 04D7 8080 01430 DEFw 8080 00940 ;Data for big numerals. as Graphics charactºrr. 0409 8883 01446 EIGHT DEFw 830.8 00950 0408 8394 01450 t.EFW 9483 0479 9683 00960 ZERO DEFW 9396 0400 9..8C 014e0 DEFW 8C94H 0478 8381 00970 DEFW 04183 04DF OCAS 01470 DEFW 0458CH 0470 9580 00980 DEFW 8095 04E1 4580 01480 DEFw 08045 047F 8044 08990 DEFW 04480 04E3 8094 01490 DEFW 9.480 0481 4180 01000 DEFW 08881 04E5 9E83 01500 NINE DEFw 836EH 0483 8094 01010, DEFW 9488 04E7 834D 01510 DEFW 00.083 0485 8088 01020 ONE DEFW 8880 04E9 838C 01520 DEFW 8C83 0487 9580 01030 DEFW 8095 14E8 SCAB 01530 DEFW 04118CH 0489 8080 01040 DEFW 8080 04E0 8040 01540 DEFW 0..080 0488 9586 01050 DEFW 8095 04EF 8887 01550 DEFW 8788 048D 8080 01060 DEFW 04080 0000 01560 END 048F 8580 01870 DEFW 8085 00000 Total errors 0491 8E83 01080 TWO DEFW 838E0 0493 83AF 01090 DEFW 88F83 NINE 04E5 EIGHT 0409 SE" EN 04C0 91 á4CI 0495 8088 01100 DEFW 08840 Flr'E 0485 FOUP 0449 THREE 0490 9140 0491 0497 8E81 01110 DEFW 818EH ,ONE 0485 SHOW 0467 ZERO 04-9 COW' 0451 0499 8780 01120 DEFW 08087 FILL 0445 CON! 044F CLS 043E START 0409 0498 8088 01130 DEFW 08880 STAPTI 0403 BILL EDGE'S ELECTRONIC AGENCIES NSW & Y V W.SA.OL DTAS. W .NT 115.117 Parramatta Rd., Concord 2137 a0SI - S SI - 5 9.99 5250 TRADING HOURS 'Corner Parra maca Rd & Lloyd George Avel bonHcordMPOgxó BOTH STORES Telephone: 1021745 3077 liwo lines) y..5 t 525 - 549.99 53505500525 - 549.99 5.00 Mon Fri .9am5.30 pm 117 York St.. Sydney Phone 267 1614 CO` 550 - 599.99 54.50 550 - 599,99 56.00Cx11 York St.Thurwiay .8 pin . 5100 or more 55.50 5100 or more 57.50 welcome here Saturday ...... 9am I2 pm All heavy or bulky items lover 20 kgl sent Comet Road Freight S 12.00 anywhere in Australia. KITS * KITS * KITS * KITS KITS * KITS KITS * KITS * '1 5 WATT BASIC AMP_ KIT EA 5 AMP POWER TEMPERATURE PROBE SUPPLY KIT FOR DIGITAL ERS KE70I 5. eo--- KE701 I. KE7010. See ETI July 83. See EA May, June 83.1' See ETI June 83. $7.50 oldi 4`' -C4 $149.00 $19.50 _a BREATH TEST LIGHT PEN FOR MICROBES ADD ON 12 VOLT FOR E s WER SUPPLY KE7012. KE7014. KE7013. See EA May 83. SEE ETI cSee EA July 83. $28.50 AUGUST $14.95 KE7002 Nicad Charger S7.9c KE 1800 DC.DC Inverter $35.00 OTHER QUALITY KITS KE4076 Digital Readout 541.00 KE 1725 Car Alarm - Delux 529.50 KE7009 House Alarm Kit S59.95 KE1100 Microwave Oven Leak Detector 51495 KE 1635 Electric Fence 515.00 KE7008 Stereo Simulalor 519.95 KE3025 Musicohiur Mk 4 595.00 KE 1630 Windspeed Indicator 549.75 KE7006 Motor Speed Controller 519.95 KE1460 Gold Metal Detector 5219.'RI KE 1631 Wind Direction 529.50 KE7007 Touch Light Dimmer 519.95 KE1940 Power Up 539.50 KE 1600 Negative Ion Generater 539.00 KE4085 300W Inverter Kit 5195.00 KE1825 Transistor Assisted Ignition 535.00 KE 1155 Voice Cancalko $22.95 KE7005 Auto Tester 514.75 KE1850 Breakerless Ignition 519.50 KE 1150 FM Mic 57.50 KE7003 Eprom Burner.Microbee $46.50 K F 1815 Frequency Meter 5119.00 KE 1130 Voice Operated Relay 515.00 ~Ow ~pow s~111110. ~a. s>11184 ~Rell11014 atsa iiiiitr sett attty ate a> ~ -BEWARE- fa-f.-.4 All kits are- not the same.- Lets look at front panels. We- know of two major kit suppliers who supply those cheap and nasty scotchcal front panels. We know of another two who supply aluminium panels. But only from Electronic Agencies can you expect in your kit a SILK SCREENED. DRILLED. ALUMINIUM panel. Ever tried to drill a 5mm hole for a LED for instance and then get rid of the burrs without scratching the panel, its not easy. Our panels sell for up to $14.50 each separately, so add that on to the cost of a kit from another supplier, and you'll see you pay no more for Electronic Agencies' quality kits. We also include FREE in kits 520 and over our very own KIT CONSTRUCTORS REFERENCE MANUAL. which is crammed full of invaluable information. (The 57 exception to the aluminium panel is our new Breath Test Kit, it has a stick on panel. not aluminium). The Edge family have been in the component retail business for 50 years. We'd call it experience! f~ - - ~I. etas and ~Jo-- - ~Ow ~Po. ~Bp- - ~O. - THE VIC-20 COLUMN * ENCOURAGEMENT'* There are obviously a lot of people who own Ozi-Soft, in conjunction with Computer Technics, VIC-20 computers. We're getting some really good is offering to donate a VIC-20 expansion board for programs coming in. No doubt the possibility of the best software item submitted to this column winning something is an added stimulation to every month. The Item making a contribution. best software The board is Australian designed and manufactured month will win a submitted to this column each and simply plugs into the VIC-20's expansion slot. VIC-20 board, donated by Ozi-Soft, in expansion It features three sockets that can be independently conjunction with Computer Technics. switch -selected, plus an on -board reset switch. Wrth it We do have an apology to make to Computer you can plug in up to three separate expansion units to Technics, who distribute the board, as we printed their your VIC-20 and avoid the hassle of plugging things in address incorrectly. It should have been Computer and out and turning the computer on and off each time. Technics, P.O. Box 25, Kogarah NSW 2217. It is distributed by Computer Technics, P.O. Box 25 Your submissions should be original and every arti- Kogarah NSW 2217 and costs $59.95. cle published will be paid for, so send them off to the All submissions must be accompanied by a signed Editor now. letter from you stating that it's your original work. The The first winner of a VIC-20 expansion board is winning submission will be judged by the Editor and (gasp, gasp! the invaders are coming) Peter Bagust, no correspondence will be entered into. All published Send entires to: The Editor, VIC-20 Column, ETI who wrote GASP. submissions will be paid for. Magazine, P.O. Box 21, Waterloo NSW 2017. -I 4.44 J;L .1 4 4 41 tGASP BY P.BAGUST":POKE36879,110 l0 PRINT",1 1 I sse GASP *5* 1! 20 PR INTLUICII9 DESTROY THE INVADERS 1WEFORE MORE THAN 95% UJF YOUR AIR IS EATEN" GASP 30 PRINT" *.EY B LAUNCHES MISSILEKEYS Z AND C STEERS ITKEY M WILL Peter Bagust, Sans Souci NSW DETONATE ITA 00 40 PRINT'lb TO BEGIN HIT ANY KEYIFORT1T010001NEXT This is 1.5k game a program. NEXT :IFPEEK(197) Hostile invaders are destroying the earth's 50 PRINT"I TO BEGIN HIT ANY KEY "iFORT-1T01000: atmosphere and our only hope is the photon -guided =64THENGOTO40 missile hidden deep in the mountainside. Unfortu- 60 F=0:A=415:PRINT"J" nately the missile eats up air as it passes so use it 70 FOR Z=1T019:PRINT"Ga. .NEXTZ is carefully. 80 PRINT"D ti.7 1/ - !S - ' a ' a7 !-1 There are seven invaders, each getting faster and 90 M=813011=7680,F=F+1IPOKE36879,14IK=0:T.INT(75/F) trickier. The game ends when all the invaders are 100 IFF-8THENPRINT",J151rl~M CONGRATULATIONSI !Q ALL ENEMYS destroyed or you have less than five per cent of air DESTROYED'IPOKE3687 9,204 remaining. 110 IFF=BTHENPRINT111 3'AN YOU DO IT AGAIN7:FORL.IT0100001NEXTIRUN Lines 10-50 are introduction. 120 IFA<21THENPRINT";1Q1A4n9M IS. GASP ass 9 UNDER 5% OF AIR Line 60 is initialisation, line 70 creates the at- LEFT tPOKE36 879,204 mosphere and line 80 makes the mountain range. 130 1FA<21THENPRINT" m GIVE UP YET LOSER?":FORL=1T010000:NEXTLIRUN Line 90 reinitialises before each frame. Lines 100- 140 PRINT"317 9141 :RAMEF"IIIPIR LEFT"(INT(A/4.18))Ií " 130 are game finishes. Line 140 prints frame number 150 R=INT(RND<1)s6)tPOKE1,32:I=1+1 and air remaining. 160 IFF=3ANDR<2THENI=I-R Lines 150-250 create and move the invader. 260- 170 IFF=4ANOR<3THENI=I-R 370 create and move the missile and 380-400 are 180 IFF=SANDR=4ANOI<8142THEN1=1+22 sound effects. 190 IFF=SANDR=SANDI>7702THENI=I-22 Variables are 'F' = frame, 'A' = air left. 'M' = mis- IFF)SANDM=I+22THENI=1-22 sile, i' = invader, 'K' = invader hit flag and 'T = lime 200 interval. 210.1FF)SANDM=I+2THENI.I-2 220 IFF>SANOM=1-1THENI=1+1 230 IFPEEK READY. 58 - July 1983 ETI MUSIC GENERATOR 1 PRINT"MDO YOU REQUIRE OLD DRTR?":00SUB98:IFR$"N"THEN10 2 PRINT"WHAT IS THE FILE NRME":INPUTBS:PRINT"PREPARE THE FILE":00SU2310 3 0010125 011 10 PRINT":}IoW MANY NOTES WILL YOU REQUIRE":INPUTR 11 °Si DIMN(R),P(A):01 14 FORB1TOR 2OO 15 PRINT"NOTE 4";B;:INPUTH READY. ETI July 1983 - 59 THE ZX SPECIALISTS ZX COLUMN The Professionals who care! TYPOGRAFIX Ralph E. Morgan, Killarney Heights NSW before printing commences; use a space fol- COMPUTERS This program can be used on an unmodified ZX81 or entered lowed by 'NEWLINE' to quickly 'fill in' any excess lines. ZX80 8K ROM, plus 16K RAM and a ZX printer, print- SNCLARI ZX 81 5149.95 (add $7. for p&p) are machine code for the hi -res printing ing up to 32 lines of text containing both upper and Lines 1-12 SPECTRUM 16K Version. $329.95 (add $7. for p&p) ZX printer manual). Lines 13-19 accumu- lower case characters. facility (see string CS. Each letter is stored as five When the lines have been entered type 'RUN' to late the data three -digit decimal numbers which are initialise. A string prompt (" ") will appear and a max- consecutive follows: imum length of 42 characters may be entered each interpreted as time. character decimal binary A Z . ,1 ... 9 iiiifilI The allowed input characters are: ... 062 00111110 IFrll\riliril`. 1 097 01100001 are: a ... z, iiiiirfili The corresponding output characters . 089 01011001~ 069 01000101 NI::iiiiJ A, inverse 0= ! (Note: represents a space. QA = 062 00111110 inverse 1. etc.) Hence, the normal output is lower case letters and Hence the user can substitute his/her own symbols if numbers 0-9 and the inverse symbols are used to HARDWARE desired. obtain capital letters and other symbols. PACK, (cased) 569.50 (incl p&p) Lines 20-35 calculate x and y coordinates of the 16K SPECIAL RAM After each string is entered approximately 15 sec- symbol to be printed. Lines 49 and 50 enter data into Suitable for ZX 80/81. onds are needed to place the appropriate data from AS. Lines 80-120 find the appropriate data in CS. CS into the array Al A total of 32 strings must be Lines 9988-9999 print out AS (see ZX printer manual). TYPOGRAFIX 2504107000507307300733050001001127 1 REM umar.rdnrirlaw~ 'STAN 00100106306406408406301504306404 2 IF PEEK 16366+e5e.PEEK 1636 8015170320240321270990200060200 3=31744 THEN COTO 5 99003012113012003097081073069067 POKE 16389,124 00012705506500000006506512700000 4 GOTO 1 8020034065000000065034020006" 5 FOR 2.0 TO 112 20 FOR L.1 TO 32 6 POKE 31744+1,PEEK (2161+I) 21 LET X=33 -L 7 NEXT I 22 INPUT TS 8 POKE 31600,63 23 IF LEN Ts>42 THEN COTO 22 9 POKE 31557, X01 24 LET N=LEN TS 10 POKE 1EE417,95 25 IFORF 65 32K D RAM PACK (cased) $125.00 (incl p&p) 11 POKE 16524,79 30 N I=1TTONNGOTO 12 DIM As(32,256) 35 LET -1) Suitable for ZX 81. No extra PSU required. Plugs into 13 LET 0S="0620970890690620000 02127000000098981073073070067065 45 FOR UY=(0I+6J=1 Td 5 expansion port behind printer. 07307705101600000812700807106906 49 LET Z=154(PO5-1)+3+(J-I) 90690570500740730730460970170090 50 LET RS(X,Y+J)=CMRf (((CODE 05003054073073073654006073073041 CS(Z+1)-28)º100+(CODE CS(Z+2)-28 X ROM CARD $69.95 (incl p&p) 030- 1+10+(CODE CS(Z+3)-26))) Fits inside our 16K Ram Pack. Has built-in printer 14 LET CS=C$+"1120640841200640 55 NEXT J 64127060060060000056058055072056 60 NEXT I interface to use a printer other than ZX Printer and 06 806812706400005608400407200000 65 NEXT L 01240100020001401461461260001270 70 005ÚB 9906 contains EPROM Burner for Basic and Machine code 04004120000000125000000000064123 75 STOP programs. FOR ZX81 ONLY 125000- 8O LET M=0 15 LET 05=0s+"0001270160400660 85 LET C=CODE TS(I) 000001270640001240041400412000,, 90 IF C>=128 THEN LET H=128 PROGRAMMABLE CHARACTER GENERATOR 12400400412000005606006805600025 91 IF C=0 THEN COTO 60 (incl p&p) 20360360240240360362521210001240 95 IF M=123 AND C(153 THEN LET S95.00 08004004000072084004056000004127 POD=C-M+57 (Fury assembled) Suitable for ZX 81/80 fitted with OF 900© 100 IF M=0 AND 0<28 THEN LET PO 16 LET C3=C5+"0600640641240640 S=C+16 8K ROM. Create own character sets, high resolution 12040064040012060064040064060068 105 IF H=128 AND C>=153 THEN LE graphics etc. FREE supporting software of Demmo, 04000804006.00015616009606006410 T POS=C-M+13 0084076004000e0e0e200eeeee080080 '110 IF N=0 AND C>=28 THEN LET P 2 Games and instructions. 06000000042025000026042032016003 OS=C-27 004002" ail115 P0511 OR PO5>50 THEN LET for 80 $38.50 (incl p&p) 17 LET C4=Cs+"0000000960960000 =IF VIDEO UPGRADE UNIT ZX 00000100100000000000176112000000 120 RETURN (Fully assembled) Upgrade to fully animated graphics 00018211000000200106100900603604 9908 REM PRINT AS 21270420100200200200200200540730 '3929 FOR I=0 TO 246 STEP e of ZX 81. Will now run in SLOW MODE. Requires 8K 05034030000030054065065000065065. 9990 FOR J=1 TO 32 ROM-- not included. 054000" 9991 FOR K=1 TO 8 18 LET CS=Cs+"1260090090091261 9992 POKE 32255+K+6+(J-1),CODE R 27073073073054062065065065034127 S(J K+I) ZON X-81 SOUND UNIT $69.50 (add $4. p&p) 06506506506212707307306506512700 999/5 NEXT K in, no extra power required, 00000010010520650730411221270050 9994 J Sell contained unit, plugs 00003127000065127065000032064064 9995 FORT H=0 TO 31 wales with 16K RAM and printer. Uses 3 channel 064063" 9996 POKE 16444+H,M games 19 LET C4=Cs+"1270060200340851 9997 NEXT M sound chips. Huge range of sounds for 27064064064064127002012002127127 9998 LET HPRINT=USA 31744 and music. 00200400012706206506306506212700 9999 NEXT I 1A 1111 Ili ENCODER Ralph E. Morgan, Killarney Heights NSW This program accepts a text or numerical data string can be saved with the encoded data. When the prog- and then encodes it using a coding key entered by the ram is later reloaded the data can be retrieved by entry SNCLAl1 PRINTER $175.00 (add $7. for p&p) user. of PHILIPS HI FI SPEAKERS AD 12250/W8 12" 100W RMS 885.00 AD 02160/SQ8 2" Dome Squaker 639.00 AD 01610/78 I " Dome Tweeter $15.30 ADF 600/4000/8 40 Watt RMS Crossover 629.30 i, ) TAX PAID MAGRATHS ELECTRONICS 55 A'BECKETT STREET, MELBOURNE, 3000 r Tele (03) 347 1122, Telex AA31001 ` bb Prices subject to change without notice. WORLD welcome here - Mail or phone orders add 52.00 up to I kg pack post Special rates for heavy items on request DIGITAL -ANALOGUE IN THE ONE PANEL [DETER! TOTALLY SIFAM NEW! EIMEMIIIMUMMEMMEMENEEMENIIIMI Standard LCD display is Front or rear of panel neutral (dark grey) but blue. mounting with a completely red or green available at extra K to present a transparent front or. if Can be programmed. C & is proud cost Illumination also available front -mounted. with this calibrated and scaled to Digital read-out m four omits as optional extra. totally new concept in optional manbiack bezel indicate any engineering units up to 9999 panel meters by Sifam (U.K.) p First panel meter of this type in / the World. Dual display shows both ohms ... ILLUSTRATION digital and analogue readout. Programmable! ... is micro 3,4 FULL SIZE processor based. la Universal mode offers selection of any one of 64 pre- programmed ranges built into these precision instruments. be and Up to 5 flags to indicate either Trend -bar of 31 segments Choice of three positrons for Can also programmed non-linear quantities scale multiplier or function grows or falls alongside decimal point or none at all scaled for selected printed scale and can be programmed to left-hand. centre or set-up zero C & K Electronics (Aust.) Pty Limited 15 Cowper Street, Parramatta, NSW 2150 A Phone now for tree, PO Box 229 Parramatta. NSW 2150 comprehensive Telephone (02) 835 0799 Telex AA23404 technical literature! Agents Melb. 598 2333/Adel. 277 32881Bns. 369 1277 COMPONENTS Perth 275 55221Hobart 34 2233/Launceston 31 6533 Personal Computing with the powerful NOW Micro Professor MPF-II AVAILABLE I AT HOME E IN EDUCATION E IN THE OFFICE FOR ENTERTAINMENT CASSETTE SOCKET (STANDARD) 1 Plus 20% Sales Tax if applicable i COLOUR TV SOCKET III VIDEO MONITOR SOCKET (STANDARD) (STANDARD) r - * Switching power supply POWER SUPPLY l_ hi- 12 * Full 49 key, keyboard SOCKET IFLOPPY DISK ()RIVE * Mixed text and graphics AND INTERFACE POWER INDICATOR * Micro-Nurse diagnostic program SPEAKER & HEAT (tests, CPU ins, RAM, ROM, etc) SINK HOLES CARTRIDGE/ MPF-II OPTIONS: SOCKET OPTION PRT - MPF-II: Text & Graphic Printer CENTRONICS .+r ¡ 49 TROUBLE FREE FSK-MPF: Typewriter type keyboard PRINTER SOCKET KEYS FDI-MPF-II: Floppy disk interface (STANDARD) FDD-MPF-II: Floppy disk drive MVM-MPF: 12" P31 green, non -glare REMOTE CONTROL/ EXTERNAL KEY BOARD 0 monitor SOCKET PIK-MPF: Printer interface for Epson * Monitor for 6502 machine code MX -80 & C. ITOH C8510 FEATURES: STANDARD programming * JSK-MPF: Joystick BASIC programming and reference manuals * Centronics interface SSG-MPF: Speech synthesis & sound * 64KRAM Cassette interface generation box * 16K ROM. Basic interpreter, monitor and * Software cartridge interface * ASI-MPF: RS232 I/O Card subroutines * External keyboard interface CCC-MPF: Chinese character * BASIC programming language (Applesoft® PAL colour card (6 colours) controller (22,000 characters) BASIC compatible) RF modulator Languages: Assembly, Pascal, Forth, Single key -in BASIC commands Video monitor output Logo & Pilot ALSO AVAILABLE FROM: EMONA COMPUTERS NSW: JAYCAR 264 6688; David Reid Electronics 29 6601. VIC: Radio A Division of Ernona Enterprises Pty Ltd Parts 329 7888. SA: Int. Communication Systems P/L 47 3688. SALES & SHOWROOM: WA: Hinco Engineering P/L 381 4477. ACT: Electronic Components P/L CBC Bank Bldg, 661 George Street, 80 4654. TAS: D 8 A Agencies 23 2842. OLD: Baltec Systems Haymarket, Sydney. (02) 212 4815 (07) 36 5183; Solex Electronics (07) 72 2015. Equipment NEWS 1: Open -frame switching power supplies :R1 f .,i!w,¡ 3. Q 1s . ely 1P`N tv. Power -One has gone into full production with its International Series open -frame switching power supplies, distributed in Australia and New Zealand by Warburton Franki. This new line incorporates well as most other world-wide re- the latest state-of-the-art gulatory safety agencies. They switching technology, in also meet the emissions limits of eleven off-the -shelf models. FCC Docket 20780 Class A and VDE 0871/6.78 Class A. Tektronix logic analysers Five package sizes are avail- Another feature is the ability The new able, ranging from 40 W to to operate from the wide variety Tektronix 1240 logic analyser is now available in 250 W. Depending on the model of ac input voltages found configurations which range in price from $10 500 to $28 000. selected, the International Series throughout the world. The Inter- offers up to five outputs, selected national Series ac input ranges A card -modular mainframe provides 16 channels of data lets to accommodate applications include, as standard, both 90 V the user select the data acquisition at up to 50 MHz. The such as small computers, termi- and 132 V for domestic and acquisition channels and speeds, 338, priced at $8960, delivers data and nals, peripherals, word proces- Asian applications, and 180 V to analysis communications 32 channels at up to 20 MHz. sors, disk drives, Winchesters, 264 V for European applications. interface support. The main- They both provide glitch capture printers and other devices using For further details contact frame accepts up to four data and three levels of triggering. microcomputer technology. Warburton Franki, 372 acquisition modules; the 1240D1 In the serial mode both syn- East- has The new switches are designed ern Valley Way, Chatswood nine channels and acquisition chronous and asynchronous data to meet VDE, UL, IEC, CSA as NSW 2067. (02)407-3261. speeds up to 100 MHz and the acquisitions can be executed 1240D2 has 18 channels and at baud rates from 50 bps to speeds up to 50 MHz. 19.2 kbps. Captured data can be i s t The 1240 has a dual w - - timebase displayed in hex, binary, octal, . and sophisticated triggering and ASCII or EBCDIC which make software analysis tools which are these analysers ideal for such Wéller Des+oldeñ> Weller's wall - all Weller tips available for the r1 WTCPN, EC2000D and . poster WMCP-EC temperature -con- Cooper Tools, the trolled soldering stations and the manufacturer of Weller W6OD line -voltage temperature - soldering equipment, has controlled soldering iron. Acces- sories are published a colour posterof also featured. its Weller For a complimentary copy of soldering and the poster desoldering tips. contact the Cooper Tool Group, P.O. Box 366, The poster depicts - by Albury NSW 2460. (060) number, temperature and range 21-5511. ETI July 1983 - 63 Component NEWS H -P expands 10 -element bargraph array Hewlett-Packard has added a new high- performance green 10 -element array to the standard -red, high -efficiency red and yellow 10 - element LED array family. In addition, prices have package interlock, which en- been reduced by up to 20% for sures correct alignment for the the HDSP-4800 bar -graph ar- longer arrays. A low package ray family, which achieves profile saves space between the both analogue and digital in- display board and filter. , dication. Yellow and green bar -graph 1 H -P bar -graph arrays are very arrays are categorised for domin- bright, typically 1.2 mcd/seg- ant wavelength and all colours ment at 10 mA for high-perform- are categorised for luminous in- Tabtek's circuit-desrign course ance green, and also feature high tensity. This assures a consistent Tabtek Electronics is to hold a two-week full-time seminar, segment -to -segment and on/off front -panel appearance. covering all aspects of both NMOS and CMOS small scale to contrast. The segments are large For more information contact very large scale digital integrated circuit design. (5.08 mm x 1.52 mm), which Hewlett-Packard Australia To be held from August 15-26 The principal lecturers will be gives a wide viewing angle. Ltd, 31-41 Joseph St, Black- University ofAdelaide,the Dr K. Eshraghian and Dr D. A. An exclusive feature is the burn Vic. 3130.(03)890-6351. at the program of lectures, tutorials Pucknell; both are well-known as and project work will aim to the authors of a series of lectures teach participants how to rapidly in VLSI system design. They will implement digital systems in be supported by Tabtek engin- silicon. eers. The course outline is given The $850 course fee covers under the headings: NMOS design notes and use of the VLSI Design; CMOS Logic De- computing facilities, as well as sign; CMOS Processing; Design luncheon and morning and after - Rules and Scaling; VLSI Design noon tea. Methods; Subsystems and Chip For further information con - Floor plans; Interfacing; Design tact the VLSI Systems Man - Automation and Chip As- ager, Tabtek Electronics, P.O. semblers; Simulation; VLSI Box 49, Rundle Street, Adel- Six -bit video flash A/D converter Testing Methods and Re- aide SA 5000. (O8) 223-7267. liability. The ADC -833 available from are controlled by two enable with a typical output Datel-Intersil is a low power, signals Manager Texas Instruments delay 20 ns. General video flash analogue enable of six -bit More information is available for National Semiconductor to digital converter. from Elmeasco Instruments Semiconductor guide It can digitise an analogue Pty Ltd, 15 Macdonald St, signal at conversion rates up Mortlake NSW 2137. (02) National Semiconductor A new master selection to 15 MHz with a power con- 736-2888. (Australia) Pty Ltd has guide of Texas Instruments' sumption of 200 mW. Two announced the appointment semiconductor products is be in ADC -833s may connected of John Eccleshall as available free of charge parallel to increase the conversion from Texas Instruments MHz to 30 MHz. Telcon takes over General Manager. speed from 15 VSI Electronics The ADC -833 is available for Amtex Electronics Mr. Eccleshall will report to distributors, operation over the industrial, Curtis Reid, Managing Director. and Rifa. Electrical Wholesaler, -25°C to +85°C temperature National In this newly created position, has range and is packaged in an Telcon Australia Pty Ltd, Mr. Eccleshall has responsibility The 128 page guide covers all 18 -pin ceramic DIP. announced the acquisition of for the component marketing product areas including memory, The analogue input voltage Amtex Electronics. operations ín Australia, ín digital logic, linear, telecom- range is +2.5 V to +10 V with The range of products includes addition to the company's research munications and microcomputers. minimal linearity error. photovoltaic systems and com- and development activities. More information about the The digital outputs are buffered ponents, switching power supplies National Semiconductor guide can be obtained from Texas three-state and include an over- and high voltage power supplies. (Australiai customises micro- Instruments Australia Ltd, flow output which allows the user Telcon is located at 36 Lisbon processors to the specifications of Semiconductor Marketing, to cascade two units to achieve St, Fairfield NSW 2165. (02) the growing number of Australian P.O. Box 106, North Ryde seven -bit resolution. The buffers 727-5444. manufacturers. NSW 2113. (02)887-1122. 64 - July 1983 ETI Audio remote control products 800-5000 Hz. The centre fre- J A Wells quency may Electronic Distributors has introduced a rangeof tolerance be speci- fied from 50 ppm electromechanical audiofrequency notch filters and to 500 ppm tuning fork oscillators. with a temperature tolerance ±1 ppm/°K to ±5 Both products, ppm/°K. manufactured frequencies from 960-6400 Hz on We had the by the Swiss company opportunity to Institut request. Ancillary modules for briefly review the F-304 filter Straumann AG, are based on a frequency division are also avail- and a 1488 Hz tuning fork made OSC-204 oscil- from the able. lator here at ETI and can report temperature independent steel The tuning fork is tempera- that both alloy performed very well Nivarox (as used in Swiss ture compensated from -55°C indeed. watches). to 85°C. Supply voltage is select- The F-304 had a The tuning -3 dB band- fork oscillator, ed between 5 and 15 V. width of 2 Hz (at 20"C) and an OSC-204, is a ILP's low distortion The F-304 electromechanical insertion loss of only 9.5 dB latest oscillator meeting MIL specifi- filter employs two gas coupled (quoted spec. 12 dB, +2, transformer cations for shock vibration and metallic precision tuning forks - -3 dB). The centre frequency ILPElectronics,of England, environment. It is available at with electromechanical trans- was better 100 ppm than ilimitof has addeda 15 select frequencies within the ducers and is available at any our measurement). VA range 1000-6000 Hz, with special frequency within the range transformerto its range.lt is The OSC-204, measured at fully 20°C was within 100 ppm (spec. encased in an ABS - ±100 ppm) and the frequency shell, with easy fixing by an variation for a supply voltage M4 bush at the base. E variation from 5 V to 10 V was Test runs have confirmed the FILTRE F only ±0.1 Hz. demand for both the lower VA The 'standard' F-304 sells for rating and the encased toroid, . $170 (+S.T.) in quantities of 10- and the is company now planning 19, 'while kttttlhr>t : the OSC-204 quality to extend the facility to cover CH t code C (pre -aging, greater than transformers up to 120 VA. 100 hrs) sells for $62 (+S.T. ). For further information, con- _s Enquiries to J A Wells Elec- tact the Australian agent, Elec- tronic Distributors,8 Rainsford tromark, 40 Barry Avenue, } Court, Dingley, Vic. 3172. (03) Mortdale NSW 2223. (02)533- 551-5979. 4896. TO THE ELECTR ICALLY MINDED. (Professionals, Hobbyists, Students & Enthusiasts.) We a wide carry range of Multimeters, Calculators, Soldering tools, Transformers, Cables, Instrument boxes, Computer Connectors, TV Aerials, Components and just about anything you may require. °2.345I MULTI - CALCULATORS SOLDERING -, I METERS TOOLS 1 CASIO RADIO UNIVERSITY 101~11111 HEWLETT FLUKE PACKARD WELLER HILLS . ._ ROYEL TEXAS DESPATCH TV i i,p Y:..y INST. AERIAL SERVICE "QUALITY COMES FIRST" has been our trading 869 George principle for many years. This enables us to give you the St., Sydney NSW 2000 (Near Harris best in service and the best in products...ensuring durability St.) in what you buy and your own guaranteed satisfaction. Tel. 2110816 2110191 MAIL ORDERS TO RADIO DESPATCH SERVICE Open: Mon -Fri 8.15am to 5.30pm Thursday night 869 George St., Sydney 2000 Tel. (02) 211 0191 211 late shopping 0816 till 8.30pm Sat 8am to 11.45am ETI July 1983 - 65 VIDEO STABILISER VIDEO SENSATION As many of you know, many video tapes - especially from the USA AT LAST have the sync pulses suppressed to prevent unauthorised copying of I the original dub. This process is fine because it hinders unauthorised A Video Enhancer/ I re-recording (dubbing) of material. It is annoying though when you Distribution Amplifier hire thé original and find that the "Copyguard" is causing problems with your TV. The AV6502 re-inserts the sync pulses automatically designed I and restores stability. EXCLUSIVELY I WARNING! The AV6502 is intended soley for the use above. for AUSTRALIA Whilst the AV6502 will virtually remove copyguard on a tape copy gryHe.NGE I (and hence restore the picture) it is against the law to unlawfully I copy copyright material. Cat. AV6502 only $79 Jaycar has had designed a high quality, high performance Video Enhancer which is specifically for the Australian 625 line 50 frame PAL -D system. i cQ[I ITt[' Australian -built unit ÓGo%ras As far as we know it is the ONLY Australian -designed, ' I ^1F,Ul availablell II But, guess what? The Jaycar AV6501 Enhancer is CHEAPER than its inferior imported Asian counterparts!! SE IS, 1 I `DF I, PROFESSOR II This unit is professionally designed and University tested) It works and it OUTSTANDING! works well. Low cost colour Cómputer SPECIFICATIONS 1 MUMnum eneencmen. not At teen .8 3d8 2MHa with APPLE compatibility 2 Enheno. a ,.NM IBror,l »capon» DC to SMM., -0.6.1.040. VALUE frequency. to 4,43 MM,, 3 Colour Su burner 046 notch tunable -/ Mlt che RAM SUPPLIED STb 0.606. all »Ringo SPED1rICAPONS 0AR0 aI w r poop then 0.075uS Ceu 4 Amplifier aley, I.,, 04. »l O 6 Sngnel handling c.ptllny not lass the, 1.35 role p -p. (Sync. In Tea. V usa M motu su, Iw^. lipped Kan M p.mw=orn.tmr. P.w STANDARD first. ..,w Power 12V AC 100mA t . ra D TV IR,/ R STANDARD /OFF, ENHANCE. /BYPASS S W I TCH, 7 Controls. ON ENHANCE Moda loa t N:.:.:I.i..,ñ stssam .nrase a, 1495° Aa cg madl e, r naa CORE/GAMMA CONTROL . ca weerN...Y 660 IN INN cdraiono.1 e n . u.rl 8 Input connector, RCA socket Cat AV6501 co,,..., to, Umrrws 9 Output connector. RCA socket S 3 .lan- I$16. 1,1110cl,wc» enw.wOwa 19.1.3.1.110. NININK,I r w 4e Canea.. arme. »rn» DESIGN FEATURES acetre ».duct» STANDARD colour lubcan ar Itou...0y, bebo.. pateo.. 1 A .rely gam notch at tM NOT A KIT wiO.ch 531c cw is to pnr*lt chrominenee to lu,nmanee error at bqh .nbance I6H5. Nmer sr Crr. rKL 1154HC .b.1I leea lag comptn»lion to ash..* iº e . N nnw.,. co a IINNI . .w m 2 A Clo»d loon con/uradon /th ceRRIR Yo. n»» BUILT, TESTED w wen -.mor 1 w table, well 41 meo gen Caoe,. nr ». . yi r 3 DC c aroma. eliminating irga .apec.tpn t, , wnh M wa.o cesa Corma... ur DC lo. appkcationt mcnorIng n. AND GUARANTEED Signal and echiwing responsa `:á,r.. VROar...aéánm. Cat YC1300 4 Low output impedance pnot to is .Store, en4bl,ng up to .. nrnww»m. outp uta te b. and Of blr re nt atoe KIT VERSION three Uhund ú a`..'. án`.n.o, to 6 A Iwel depnaant cloud loop upon o, Gamma control t'eme') :C 6 Clip on negah,e gong signan at -67 volts Into 75 ohms to prevent ONLY $39.50 »in. wnm sync erras owne to °yerno.. Cat No. DESCRIPTION OF KIT Ref, PRICE » - KA1300 FUZZ BOX COMPLETE EA 1/81 S 19.50 KA1320 LE GONG EA 3/81 S 13.95 14.95 K1141346 PC BIRDIES SHORT FORM EA 5/81 S KÁ1370 PHOTON TORPEDO EA 9/81 5 29.50 KA1400 METRONOME EA 1/82 S 16.95 KA1402 EPROM PROGRAMMER EA 1/82 S 59.00 KA1406 CUDLIPP CRICKET SHORT FORM EA 2/82 S 12.50 041408 DIGITAL STORAGE CRO ADAPTOR EA 2/82 0110.00 KÁ1430 VOCAL CANCELLER EA 4/82 S 19.50 KÁ1432 VOX RELAY SHORT FORM EA 4/82 5 14.50 osO. EA 6/82 S 14.50 r . ^ 041450 GUITAR BOOSTER 041452 SUBWOOFER MOSFET AMP EA 7/82 S 79.00 EA 8/82 S 79.00 gn e «.S KA1454 SUBWOOFER ENCLOSURE == KÁ1476 STEREO SYNTHESISER SHORT FORM EA 9/82 S 39.50 KA1478 STEREO SYNTHESISER COMPLETE EA 9/82 S 49.50 11 KA1482 POWER UP KIT COMPLETE EA 11/82 S 39.50 - r/- KA1484 SUPER SIREN SHORT FORM EA 11/82 S 5.00 KA1490 BOGGLE GOGGLES EA 12/82 S 9.50 K41492 PH METER LCD EA 12/82 , 5 69.00 KA1494 PROBE FOR PH METER WITH BUFFER S 69.00 KÁ1498 AM WIDEBAND TUNER EA 12/82 S249.00 "Most Apple Soft II BASIC programs will run on the MPF II. KA1500 LED HEAD SHORT FORM EA 1/83 S 9.95 KÁ1510 STEREO SYNTHESISER SHORT FORM EA 4/83 S 11.95 KÁ1515 ALIGNMENT KIT AM TUNER EA 3/83 S 7.95 KE4050 50 WATT AMP MODULE ETI 480 S 23.00 KE4052 100 WATT AMP MODULE ETI 480 S 27.00 241))1W KE4064 PREAMPLIFIER MODULE ETI 480 S 30.00 PURPOSE PREAMPLIFIER ETI 445 5 7.99 monitor GENERAL vídeo KE4090 ETI 446 S 12.00 Sc,een - 12" KE4092 AUDIO LIMITER COOLING ano 80 char. MICROPHONE PREAMPLIFIER ETI 449 S 5.50 ~hoy - KE4094 BALANCED ac ter 24 line, 330 S 29.50 by KE4105 CAR ALARM ETI Input RCA ETI 458 S 59.00 FANS - KE4205 LED LEVEL METER BOnowidet 10117. S 26.50 - KE4206 MC MOVING COIL PREAMPLIFIER ETI 478 20M Mt S 19.50 KE4207 MM MOVING MAGNET PREAMPLIFIER ETI 478 Input sig. 0.5 to 2.0 S 59.00 KE4210 MOSFET AMPLIFIER ETI 477 pp composite, cinc reap. KE4220 150 WATT MOSFET AMPLIFIER ETI 499 S 79.50 240V AC & 12V DC KE4222 150 WATT MOSFET PREAMPLIFIER ETI 498 5 39.50 Weight 8.6 kg KE4225 BRIDGING ADAPTOR ETI 479 S 9.95 KE4405 /- 15 VOLT POWER SUPPLY ETI 581 S 17.50 KE4410 POWER SUPPLY 13.8 VOLT/10AMP ETI 160 S 79.50 S YM2uuv KE4505 SOUNDBENDER SHORT FORM ETI 492 24.50 Cat $199 0E4552 UHF CONVERTOR ETI 735 S 32.50 KE4554 VIDEO MODULATOR ETI 760 S 12.99 KE4560 LOW OHMS METER ETI 158 S 29.50 49.50 KE4570 POWER SUPPLY 0 - 30 VOLTS 1 AMP ETI 162 S green screen 644 0169.00 ,r.. KE4600 MODEM SHORT FORM ETI le KE4602 MODEM COMPLETE ETI 644 .11441411> uwA seúeá::nm 5 36.50 KJ6502 SYNTOM DRUM SYNTHESISER KIT 524.95 MICON DATA CASSETTE KIT S 69.95 K J6508 CHORUS GENERATOR t44wATTe-1t9.t19.21ai KJ6510 SHORT FORM IONISER KIT S 14.50 Cat. YD1950 ONLY $49.50 S 29.50 k2.514 KJ6511 FULL IONISER KIT , 027.50 G. IR 20 Passive Infra -Red Detector 28 PIN A truly extraordiná y device. The passive IC SOCKETS IR detector is the classic adaption of mil- Z//l itary hardware for commercial use. This YOU MUST BUY THESE FROM USII device is basically a box measuring 96(W) WE DARE YOU TO FIND THEM FOR LESSII Buy in x 102(H) K 66(D)mm. On the front face is 102mm bulk and savell NORMALLY 60c & 55c 10+ a "window" with a deep red IR filter across NOW 30cents each 10 up it Directly behind the window is a high gain 20cents each 100 quantities, I IR "antenna" or "lens" (choose which word 15cents each 1000 up you prefer). At the focal point of the antenna Quality US-made Robinson -Nugent Cat P16507 is a super-duper IR photodlode. All prices Include sales taxi! The heat radiated from 'a human body can be 94, n 6Sem FROM detected up to 20 metres away! The unit will SAVÉ operate A reliably over a very wide temperature Specification ONLY - range and Is not nearly as subject to the FORTUNE annoying "false Range: 20 metres 90° heel of tee using 9 15 CENTS!! triggering" found so often in snort range microwavé or ultrasonic and 9 long range :ores surveillance systems. r IO2mm a The microchip electronics Size: 96mn 66rrrn In the unit ensures Sensor: Dual element pyro-electnc detector further reliable operation with a "memory latch" system. A LED on the panel indicates Temperature Range: - 10'C to 40'C EXPERIMENTER that the unit has been triggered. Alarm Memory: LEO Warm stored in armed state Cat LA5010 displayed in dserm state BREADBOARDS Track Test: operates m disarm slate LED Cat P88810 WBDN 100 holes $3.45 Relay Output' SPCO 30V 14 Cat PB8812 WBTN 640 holes $10.95 s14.? Current Consumption: 25 me typical at 12V DC Cat PB8814 WB2N 840 holes $16.95 Supply Voltage: 12V DC (10.16V DC) Cat PB8816 WB4N 1680 holes $29.50 Will directly interface with 90% of Weight: zoos. Cat PB8818 WB6N 2420 holes $45.00 existing alarm systems... VALUE! 1N914 DIODES - INCREDIBLE SAVINGS The 1N914 (or 1N4148 if you like, is probably the most popular diode in the HEAVY DUTY MAINS FILTER history of electronics. We probably use over 1,000,000 a year ourselves!! We have made a bulk scoop purchase and for JUNE ONLY we can pass them on at great savings! Because they are so low in price anyway, we must sell in minimum lots 'of 500. .r. Cat No. Description* 500 1,000 10,000 ZR1100 1N914/1N4148 0.035 0.028 0.02 Prices INCLUDE sales tax!! F * The glass envelope is really too small to have markings, however some are branded. We reserve the right to supply units that are the same size as the 1N914/ 1°k $74SO 1N4148 but are electrically superior. J PCB MOUNT There are an enormous number of Desk- top micros now having problems with mains SCREW FROM $ 1 25 borne interference. TEFiMIÑALS Our MS4002 filter has been invaluable where mains interference Is only marginal We now stock two (2) types of 4 way and 8 way. Great for the sn. problem. This unit (illustrated) costs only rugged connection of 240V or other heavy duty wiring to PCB's ` $14.50 and is supplied with full data. when solderless disconnection may be required at a later date. For much more serious problems, or when I t t, a free standing unit (not illustrated) is re- 4 way Cat. HM3207 PRICE quired the MS4004 is ideal. It will pass 2 $1.25 ¡ amps (conservative) at 240V AC. This 8 way HM3208 unit Cat PRICE $1.95 + a w/. is grey painted metal case that plugs into s a standard mains socket On one end of the EXPERIMENTER'S MAGNÉT KIT case is an unswitched 240V outlet Virtually the only thing that comes out of this Magnets never cease tó amaze - yet most of us know very little socket Is mains. All frequencies above 50 about them. Hz are very heavily attenuated. Ideal for With this in mind Jaycar has had a special "Magnet Kit" produced. problem areas. The kit contains: 2 very powerful Ceramic magnets, flux concentra- Cat MS4002 $14.50 Cat MS4004 $99.00 tor, pole pieces and a short manual written by experts in magnetism. Magnet experiments are also shown as well as a technique to actually make your magnets stronger!! 9 VOLT BATTERY HOLDER/ Cat. KJ6512 CONNECTOR ------ONLY $495 BRILLIANT!!! ONLY $295 NEW New range of Super -Bright LEDs, Due to the Incredible demand for our 200mCd super -bright LED, we have increased the range available. Now you can get super -bright in green & yellow as well as a new massively powerful 500mCd red! This new red . LED will give you 500mCd @ 20mA or -wait for it - ONE CAN- DELA of light at 40mAl Remember, a typical 15 cent 5mm red LED gives only 1.8mCd at 20mA, the difference is staggering! Cat No. Description 1-9 10+ ZD1790 200mCd SB Red LED S .69 $ .62 ZD1792 500mCd SB Red LED $2.95 $2.50 ZD1794 80mCd SB Green LED S .95 S .85 ZD1795 16OmCd Yellow S $ SB LED .95 .85 MAGAZIN E Keep your precious (and expensive) BINDER The 216 cell 9V battery is a common source magazines in order for easy references. of power for many projects. The problem is, LOW IMPORT PRICE Smart blue colour with gold however that they are difficult mount. lettering. ONLY $4.95 to Heavy gauge and richly chromed metal You usually end up letting thé battery bounce 4 up $4.50 each fittings. Cat- 887000 around the box tethered to its battery snap. This great unit (pictured) enables you to secure SEE THE OTHER JAYCAR ADS the 9V cell as well as connect to it. Great for IN THIS MAGAZINE FOR OUR any portable equipment! JAYCAR STORE ADDRESSES AND Cat PH9232 ONLY $2.95 PHONE NUMBERS.. . A laboratory standard function and pulse generator Pay, Here is another of our laboratory standard test equipment projects. This function and pulse generator covers the range from 1 Hz to 1 MHz, generates sine, square, triangle ramp and pulse waveforms. It features digital readout and six output voltage ranges, from 10 V down to 30 mV peak -to -peak. It has positive - and negative -going pulse outputs and the pulse width can be set from one second to 100 ns in seven ranges. In addition, it can be swept by an external sweep generator (to come ... ). David Tilbrook APART FROM a good multimeter and a var- The pulse output can be triggered, double - The next question I posed was, what func- iable, protected power supply or two, every triggered, gated or swept. The pulse period is tions and features of the Wavetek could be electronics workshop worthy of the title, and variable between 20 ns and 10 000 seconds done without or would not be required by the every electronics enthusiast of serious in- while the pulse width is variable between serious enthusiast or general electronics tent, needs a function generator of some sort 10 ns and 100 ms in seven ranges. The trans- workshop? with performance adequate for the various ition time is variable, too, from 7 ns to 50 ms For a start, the frequency range is prob- tasks the operator is likely to engage in. in seven ranges. The amplitude, dc offset and ably far too wide. I settled on 1 Hz as being a Now, that's a pretty vague specification frequency stability in linear mode (to practical lower limit after considerable dis- These days, the 'various tasks' one can tack le 500 kHz) is ±0.059k. over 10 minutes, cussion among staff and associates. This is might range from amplifier system perform- ±0.25ek over 24 hours. low enough for a great many slow digital ance checks to the design and construction of They are the main performance paramet- operations and in linear applications is good a microprocessor system. At some stage of ers of the Wavetek 166. It has a circular for checking loudspeaker drivers for 'poling', the task being tackled, a signal source of frequency -setting dial with calibration etc. The upper limit, I knew, would be some- some description will be a necessity, like as markings around the skirt. The dial fre- what dictated by the sort of technology I not. I had to set some sort of performance quency also indicates the start frequency of a would be restricted to using, given the re- specification when setting out the initial re- sweep range. It has served us extremely well straints of component availability and cost. quirements of this project and cast around to date. However, quite a few of the perform- Without looking at the latter too closely, I for a good starting point. ance functions and features have not been thought an upper frequency range of 1 MHz The best starting point I could find was needed. was a desirable goal. right under my nose: the Wavetek function and pulse generator we've had in the lab here at ETI for some years. Now, Wavetek SPECIFICATIONS ETI-166 FUNCTION/PULSE GENERATOR is to function generators what Tektronix GENERAL - is to oscilloscopes, so I figured our generator was a fair place to start the Function outputs 'sine process. triangle Our model 166 Wavetek covers 0.0001 Hz square to 50 MHz. It has sine, triangle, ramp, sawtooth square and pulse outputs (TTL level, posi- tive- and negative -going). The function out- Frequency range 1 Hz to 1 MHz in seven ranges put can be varied from 0 to 30 V peak -to - (square to 100 kHz only) peak (open -circuit, 15 Vp-p into 50 ohms). Pulse outputs positive going } The dc offset can be varied over i TTL level with pullup to 5 V output negative going ± 10 V open circuit, ±5 V into 50 ohms. The (repetition rate set by frequency frequency can be swept over a 1000:1 range, control, 1 Hz to 1 MHz) log. or linear. The output can be amplitude Pulse width range 1 sec. to 100 ns in seven ranges modulated and the waveforms can be trig- Frequency display 31/2 -digit, 1 Hz gate time, 1.000 Hz to 1.000 MHz gered. On sinewave output, the distortion is Sinewave distortion typically less than 2% THD; diode shaped less than 0.5sí between 10 Hz and 100 kHz, External sweep input sweeps generator over one -decade range; 1 V peak rising outside those limits. The triangle Output voltage ranges 10 V, 3 V, 1 V, 300 mV, 100 mV, 30 my (peak -to -peak) linearity is greater than 99g between 0.005 Hz and 100 kHz. 68 - July 1983 ETI VanoIóordpubs gsnsTattoT DC OUTPUT RANGE OFFSET FUNCTION OUTPUT FUNCTION r SELECT ATTENUATOR OUTPUT OUTPUT AMPLIFIER POSITIVE 1E7615201 CURRENT SOURCE M OUTPUT SET .1 SINE CONVERTER BUFFER FUNCTION SELECT SCHMITT TRIGGER PULSE TTL-LEVEL J L OUTPUT LEVEL SHIFTER PULSE GENERATOR "L.r PULSE OUTPUT F REOUENCV SET FREOUENC RANGE PULSE WIDTN SET PULSE WIDTH F R EO UENCI RANGE COUNTER NEGATIVE L CURRENT SOURCE e HF i I ] I_I I.1= J I DISPLAY 12V MAINS 12 V INPUT 5V Figure 2. Block diagram of the ETI-166. Two constant-current sources, +1 and -I, are at the heart of the main oscillator. This is achieved by the function select control. A diode' steering' network, diodes A -B -C -D, allows +1to charge the Integrating The capacitor voltage signal is buffered and the triangle/sawtooth wave capacitor and -Ito discharge it. The frequency range switch selects the integrat- passed to the function select module. To produce a sinewave, the buffered ing capacitor required. The oscillator works like this: let's assume the Schmitt triangle wave is passed to a sine converter, whose output passes to the trigger output is high (+ve) to start with. Diode D will be reverse -biased and function select module. diode C will be forward -biased, reverse -biasing diode B. Diode A is forward - The Schmitt trigger output is passed to a level shifter so that the square wave biased and thus the integrating capacitor will be charged by +I. signal swings between 0 V and the +ve supply rail. The frequency counter The voltage on the capacitor will rise linearly until it reaches the upper takes its input from this point, as does the TTL-level pulse generator module. threshold of the Schmitt trigger. The Schmitt's output will then swing negative, The latter produces complementary pulse outputs with very fast rise and fall reverse -biasing diode C and forward -biasing diode D. This reverse -biases diode times. This employs a TTL monostable multivibrator, a switch .selecting A, and diode B will thus be forward -biased, allowing -I (a current sink) to appropriate capacitors for the pulse width range and a pot. providing pulse discharge the capacitor. width set. The voltage on the capacitor will fall linearly until it reaches the lower threshold The output of the function select module passes to the output amplifier via an of the Schmitt trigger, whose output will then revert to the high state, commenc- attenuator. The output amp, includes a dc offset adjustment that can be varied ing the process once again. with a pot. As the diagram shows, the capacitor voltage is a triangular wave, while the Sweep -generation circuitry has not been included in the ETI-166, simply Schmitt trigger output is a square wave. because we couldn't fit it in a reasonably -sized off -the -shelf case! Apart from By varying the actual current sourced and sunk from +1 and -I, the oscillator that, we realised that a stand-alone sweep generator could be used with many of frequency can be varied. Thus, voltage or current control of the frequency can be the commercially available signal generators so would be suitable as a project in incorporated and the frequency set control is a potentiometer. To produce a its own right. sawtooth wave, the charge and discharge currents have to be different. Constructionally, the ETI-166 has been divided Into logical modules - the For a ramp -up wave, the integrating capacitor is discharged quickly by main generator, the frequency counter and display and the output amplifier. The increasing the current sunk by -I. For a ramp -down wave, the capacitor charge latter has been dubbed Project 1520 and appears elsewhere in this issue. The current supplied by +I is increased. other modules will appear in following issues. What about the function outputs? They of volts peak -to -peak, or was some other The ability to vary the output range were obvious: sine, triangle, square, and arrangement tolerable and easier to between zero and a defined maximum is de- ramp-up/ramp-down. The pulse outputs achieve? A search through the data books sirable. The Wavetek has an 'output atten- were a little trickier. The general consensus and a little quick experimentation soon set- uator' variable in 20 dB steps, but from ex- was that it would be desirable to set the pulse tled the question. The former was certainly perience we had found the intervals too great width over a wide range and that variable possible and considered generally desirable. on many occasions so I settled on having transmission time was rarely required. As The goal was to get a maximum output 10 dB steps for the output attenuator on this TTL level outputs with resistive pull-up suit level of 10 Vp-p into 50 ohms (20 Vp-p open generator. As the de offset facility had come both CMOS and TTL circuitry, TTL level circuit) right across the frequency range -a in handy - particularly when working with outputs only were settled on. Complement- tall order, because the output stage is re- digital circuitry - provision had to be made ary outputs (negative- and positive -going quired to deliver around a quarter of a watt. for that, too. Much digital work is done with pulses) were considered to be desirable. In addition, it would need to have a band- high-level signals, while much audio work is The function output level, and the desira- width of at least five times or more than the done with low- and high-level signals, rang- bility of do offset adjustment, came in for frequency range of the generator to accom- ing from millivolts to volts. The output at- much discussion. Should the generator be modate the harmonics that go to make up the tenuator has to cope with those require- capable of driving a 50 ohm load at some tens non -sinusoidal functions. ments. Ell July 1983 - 69 pcmDscR lee 1 A real smoothie. Output of the triangle wave generator at 1 MHz; expanded trace on the right. that is hardly reasonable to achieve. Keep- lab. Wavetek was rarely used. That sort of ing that in mind, I set about putting numbers thing's essential on an RF signal generator to the various performance figures required (... all right, all right - we'll get round to of the generator project. it), but of rare application in a function An obvious first one is sinewave dis- generator such as this. Hence, no modulator. tortion. Wavetek's lower cost, lower perform- I decided that providing gating facilities ance function generators quote a sinewave on the function output was a specialised ap- distortion figure of 1% to 500 kHz for a plication. If you need it, then the ETI-124 generator going to 5 MHz. Other brands Tone Burst Gate (Nov, '75) should suit most quote 2% to 5% distortion figures. If you applications. Then came sweep. The ability to sweep a generator over a given frequency range, The technology particularly where you can preset the 'start' SCHMITT and 'stop' frequencies, can be extremely INTEGRATOR TRIGGER The fundamental circuit of a function handy. It might be something rarely used, generator is shown in Figure 1. This consists but when you need it, there's no satisfactory 1lUL of an op -amp integrator followed by a substitute. Some applications, particularly 1: Schmitt trigger with a feedback path be- in the audio field, require sweep facilities tween the Schmitt trigger's output and the often. There was no getting away from it - integrator's input. Such a circuit is arranged the sweep facility was necessary. such that, at power -on, the Schmitt trigger Triggered and gated signals are used less output goes hig and charges the integrator's often, except in certain specific fields such capacitor. The integrator's output rises - Figure 1. Fundamental arrangement of a function lin- as loudspeaker evaluation. It was decided generator oscillator. early until the Schmitt trigger's upper that this generator could do without the threshold is reached, where the output goes nicety of triggering and gating facilities. low. The integrator's capacitor then dis- An important consideration on any gen- want to measure the total harmonic distor- charges linearly until the Schmitt trigger's erator is frequency readout. There are two tion of an audio amplifier, then you really lower threshold is reached, where the output fundamental ways one can approach this - need a special low -distortion oscillator. Thus, reverts to the high state once again. the mechanical way or the digital way. The it seems to me that a sinewave output distor- The variable resistor in the diagram is mechanical way has the advantage of being tion of 19 to 2% would be tolerable, if not there to indicate that the integrator's charge cheap and pretty direct. The Wavetek 166 more than adequate. and discharge rate can be varied (the rates has a calibrated skirt on the frequency knob. Triangle and sawtooth linearity should be will be the same), thus varying the oscilla- That's fine, except in those (increasingly at least 95%, preferably close to 99%, right tion frequency as the time taken to reach the numerous) applications where you need to across the frequency range. Schmitt trigger's upper and lower threshold know the frequency to, say, 1 Hz in 1 kHz. Frequency readout is important. When is varied. Out with the digital counter! That's all right, messing around with audio filters, modems To obtain a sinewave, the triangular wave except where you need to use the counter for and the like, the ability to measure at least output is rounded, or 'shaped', with a special other things while you're using the 1 Hz in 1 kHz is highly desirable. A simple circuit. Sawtooth waveforms are generated by generator. 31/2 -digit counter will allow you to read 1 Hz having different charge and discharge times I opted for digital frequency display. This in 2 kHz (for argument's sake ...), which is for the integrator. A 'ramp-up' waveform is gave me an additional option - the ability to quite sufficient in a huge variety of applica- generated by charging the integrator's use a 10 -turn potentiometer in place of a tions. If you want more accuracy than that, capacitor slowly and discharging it quickly. conventional pot. for the frequency setting then it's time to dig out your six- or eight - A 'ramp -down' waveform is obtained by control. You don't have to, but the possibility digit counter! charging the capacitor quickly and discharg- is there. The output attenuator, as stated earlier, ing it slowly. The basic functions and features settled on needs to be able to provide signals down in There are a number of special ICs avail- turned out to be: the millivolt region on one hand, yet the able that provide the fundamental circuit maximum output level desirable was set at blocks to make a function generator. The 1 Hz to 1 MHz frequency range 10 Vp-p. Then there's the 10 dB steps. Well, XR2206 and the 8038 are probably sine, triangle, square, sawtooth the most all that's pretty simple. A six -range atten- well-known ones. Unfortunately, (ramp -up and ramp -down) and pulse neither uator will give steps of 10 V, 3 V, 1 V, meets most of the performance outputs requirements 300 mV, 100 mV and 30 mV. A pot. simply set down earlier in this TTL level positive- and article. At best, the allows infinite variation over whatever max- XR2206 will get negative pulse outputs with only to 150 kHz and the -going imum level range is set attenuator. variable width on the waveform' 'trueness' begins to fall off once it The pulse width range was not so difficult gets past about 20 kHz. It's a fine sweep facility IC for non- to define. From experience, pulses greater critical applications, output voltage range from millivolts such as a low-cost than one second wide are not often en- 'knockabout' function generator. The 8038 is to at least 10 V countered or required, so that fixed a reason- better it will comfortably get to 500 kHz, do offset provision - able upper limit. Pulses around 100 nano- but, waveform digital frequency display. again, trueness is nothing seconds wide are encountered more wonderful well below that limit. a As the project was to be part of the 'lab - often, as well as whole host in between. A To meet the requirements set down standard' series, I next had to define vernier control would permit variation up to earlier, I had to tackle the project in discrete lab -standard' with regard to function a set maximum pulse width. Thus, I made the 'blocks'. The block diagram in Figure 2 is the generators. pulse width ranges 100 ms -1 s, 10 ms - result. That is the overall block diagram of 100 ms, 1 ms -10 ms, 100 us -1 ms, 10 us - the ETI-166 Function/Pulse Generator. The definition 100 us, 1 us -10 us and 100 ns-1 us. Constructionally, the ETI-166 has been di- For the sweep function, being able to vided into logical modules - the main This proved a difficult task as there are con- sweep over a three -decade range (1000:1) is generator, the frequency counter and display flicts between desirable performance and desirable, but problematical to achieve. I set- and the output amplifier. The latter has been reasonably achievable performance. It's like tled for being able to sweep the generator dubbed Project 1520 and appears elsewhere saying a desirable goal for a jogger would be over any one -decade range. in this issue. The other modules will appear to jog up Mount Everest and back, but it's one We found the modulation facility of the in following issues. 70 - July 1983 ETI puoDaca '520 Wideband amplifier module Here is a wideband amplifier capable of driving a 50 ohm load with an output capability of 10 volts peak -to -peak. It has many applications, e.g: improving the sensitivity of a CRO or a counter, as a video amplifier or boosting the output of a signal generator. David Tilbrook THIS PROJECT is, in effect, the first part of the ETI-166 Function Generator, the re- mainder of which will be described over the next few issues. We decided to publish this section of the function generator separ- ately so that a separate pc board could be . I, designed and made available for any appli- , I cation needing a low distortion, wideband amplifier, such as a transmission line driver or video amplifier. 110 C711 r In the Function Generator this project is used as the output amplifier since its wide inntrbl frequency response and 50 ohm output im- pedance enable it to provide large signal level sine and triangle waves (up to around 8 V peak on a 12 V supply) to a broad range of load impedances. In order to keep both the design and the construction relatively simple it was de- T,s, cided to use an integrated circuit, if possi- ble, to form the basis of the project. The -ST main problem was to find a device capable of the necessary speed. In order to produce a 10 V peak -to -peak triangle wave at a frequency of around 1 MHz, a slew rate of approximately 30 volts/microsecond would be a neces- sary minimum. Although this is not beyond the capability of a number of high speed operational amplifiers, some of these de- vices achieve a high slew rite by means of a relatively complicated 'feed forward' tech- SPECIFICATIONS ETI-1520 WIDEBAND AMP MODULE nique which can make the device prone to instability on some types of load. Further- x (approx. more, some of these devices have poor Gain 9.2 20 dB) depends on R4 gain at high frequencies even though their Maximum output slew rate figures are good. voltage swing 10 V peak -to -peak into 50 ohm load After a look at the devices available, the with +/-15 V supply (20 Vp-p no load) CA3100 wideband op -amp was chosen. Frequency response This device is manufactured by RCA and is before slew rate limiting dc - 1.3 MHz (20 Vp-p output) almost ideally suited to this application. It (power bandwidth) do - 2.2 MHz (10 Vp-p output) dc 4.5 MHz (5 Vp-p combines both high slew rate and good - output) (below 5 Vp-p output, feedback gain at high frequencies. It is also conve- limits top end frequency response) nient to use since it has a standard op -amp Frequency response do -5 MHz +0, -3 dB pinout. do - 13 MHz +0, -10 dB The output drive capability is, of course, do - 30 MHz +0, -20 dB not sufficient but this is easily solved by Distortion @ 20 Hz @ 1 kHz @ 20 kHz following the op -amp with a unity gain emit- (at 1 V RMS output) 0.03% 0.03% 0.03% ter follower stage. This results in a general Noise (20 kHz bandwidth) purpose wideband amplifier capable of Input terminated by 1k 10 nV/ Hz Input short circuited 8 nV/ Hz a driving 50 ohm load and having a slew Current consumption 25 mA (no load) rate around 40 V/us. The bandwidth of the +/-15 V supply rails) circuit is approximately 15 MHz for a 1 V RMS output signal level. ETI July 1983 - 71 Around ALTRONICS KITS 51 COST MORE more REASONS * PREMIUM COMPONENTS USED eg. MOTOROLA, FAIRCHILD etc. * QUALITY INSTRUMENT CASES SUPPLIED WHERE INDICATED * EVERY LAST NUT AND BOLT SUPPLIED, EVEN SOLDER * IC SOCKETS SUPPLIED WHERE INDICATED. Your finished product will look so good your friends won't believe you built it. OUR BEST SELLING POWER SUPPLY KIT EVER DIGITAL FUNCTION ANALOG / DIGITAL 3-32 volt output at 1 amp UNDER $40 THE ALTRONICS POWER SUPPLY FREQUENCY METER GENERATOR STORAGE CRO Based on EA CM 317K Project ) ADAPTER workshop, and hobbyist should 7 Digit Resolution, measures period and (with digital display Every school frequencies to 500 MHz get one now 111 Nor Sine, triangle and squarewaves EA 1980 and March 19811. Professional unit - cost a fraction of J similar built-up units. 15Hz- 250KHz. rC(See fe+ ES) pIOn4 ~WAY atT%R 1111 41) [Z.:1950651 ° I .. .a. . .y, rw:x.,raat,a-.a. v Fully projected from thermal runaway Unit enables indefinite Storage Of non - and short circuits. repetitive waveforms at a fraction of the voltage and current metering. This Is easy Cost Of Conventional storage CRO's. National project "so to construct", virtually The esséntial TO -3 regulator plus powerfin heatsink. all components mount on one single PCB, most piece Of lest gear (second semiconductors A-D/D-A Conversion tech- a on Fully documented, every last part included. ensuring success even for the "not so exper- only to good multimeter) any hobbyist's niques allow analog Signals UP tO 100KHZ tO bench Is some kind Of audio Signal generator. K3200 ienced" Constructor. be stored two channels while in digital S42.50 This design utilizes the latest circuit techniques mode positive and negative edge triggering Use Of the latest LSI circuitry ensures to produce stable, low distortion waveforms. impeccable performance from the completed AC/DC/HF and LF rejection tlmebau A versatile a bargain price. tracer for unit. This is further ensured by our use of truly unir at accurate frequency measurement ETI 162 BENCH SUPPLY accurate down to 1.9Hz Analog top grads components. 4 digit frequency readout (eliminates mode - 1.3 30V 1 Amp lus Digital Mode delayed tr.gger - NOTE: use the tiresome dial calibration) accuracy lOusIs (Altronics only specified -typical sensitivity 160MV P . With voltage and current limiting intersll LSI beware of inferior kits that 2%. - -P 1 MEG - ranges (Analog) standard TTL and CMOS levels ell 162 POWIR SWIM do not conform to the original design, 3 overlapping al, x10,11100. , r Nominal 3.15 volt supply (Digital). Frequency measurement to 500mHZ (with 600 OHM Output -continuously variable 3MV-2,5V P -P. The feature% of cols 4, optional Prescaler) in 3 ranges - 0 10MHz, unit are to numerous Distortion sinewave : less than 0.7% to list, yet is O 50MHz, 10-500MHz 4 gating times - simple to Operate. - W 1KHz. 0.01, 0.1. 1, 10 seconds. Be assured of qualify with an Linearity triangle wave : better than I% Period - 2. measurement for accurate low W IKHZ. Altronics Kit. frequency Counts, 4 ranges - 1, 10, 100, 1000 Squarewave rise time - 6V/u: maximum input cycles resolution 0.1us. 1. Genuine National A -D Conversion Chips Output. not High Input Sensltivlty IOMV to 30MHz. Amplitude Slabitlly better than 0.1dB second sourced dropouts. - - 2. All IC sockets Overload and short Circuit 100MV at 50MHz W 1MOHM Input on all ranges. provided 127 total - you protected. imped nO Voltage and metering. ance, 200MV w 500MHz w 75 OHMS input Day more) Current With the exception of the display all 3. Low Capacitance Coax and a full metre Regulation - better than 0.2% zero to Impedance. COrnponents mount on a single PCB making full load Accuracy typically better than of rainbow cable. - 0.005% this kit suitable for all eenstruelors. 4, Full rnstruttlons Hum and noise on output - less than uncallbra led. and every last nut, bolt 1MV at full load. and wasner. 5. Deluxe mini rack LED Indication of currant limit. Exclusive AltroniC Kit Features K2505 585,00 cabinet. Exclusive - fully S.E.C. Certified Mains IC sockets provided throughout K2600 S189.00 Transformer supplied. low aging 10.000 MHZ XTAL. If you're considering buying this kit from Genuine Fairchild High Brightness FND your local Supplier of One of our competit- 507 display's. ors - first ring and ask them if the mains Quality ABS plastic case - deluxe front transformer is S.E.C. certified to ASC126 - panel. chances are that it won't be. Complete kit as specified by EA includes DIGITAL LED NEW DELUXE FINISH Instructions, all Cables and every last nut, K3205 $49.50 We are pleased to announce the release of bolt and washer. CAPACITANCE the Digital Capacitance Klt housed in our K2500 Deluxe H 0410 ABS Insrument Case. 5119.50 METER This superb Test Instrument Kit now Compli DUAL TRACKING ents our lop Selling Digital Frequency POWER SUPPLY Counter and Function Generator Project Kit. DECIMAL POINT FOR K2500 Electronics Australia Project. Measures Capacl- 1.3 tot 22V @ 2 AMPS :+5V 90.9 AMPS K . tance Of Doth polarized and non-poiarlZed READ FREQUENCY DIRECTLY IN MHz 2521 ONLY $55.00 capacitors from 1 picofarad to 99.99 micro - and PERIOD IN US. farads In 3 ranges. Check values Of unmarked Capacitors, K2502 57.50 especially those little trimmers that are never Coded. 0.11141. CAPACIT ANC. YE lee Select precise values for filters and timing networks PRESCALER FOR K2500 within ease. EXCLUSIVE TO ALTRONICS ALLOWS FREQUENCY MEASUREMENT Each kit Includes precision measured TO capacitors for aCcurate calioratiOn Of each 500MHz range. The ideal for power supply the audiophile STANDARD VERSION K experimenting with linear OP amp K2501... (essential option) ...526.00 2520 designs with Deluxe Instrument Case (in metal case) Same Specifkations . $41.50 In which split supply operation ensures improved distortion and noise figures. Fully protected against short circuits, overloads and thermal runaway. LED indicator for regulator dropout. Floating ground. Uses 0.25% linearity 10 turn pot - tracks within 1MV. Voltage adjustable to within 10MV. K3220.. (EA MARCH 19821..586.00 TRANSISTOR EXPANDED SCALE MICROWAVE OVEN TESTER LED VOLTMETER LEAK DETECTOR 13.8V HIGH HAS MANY APPLICATIONS CURRENT SUPPLY us et. 724 i -"'""""- t \ 1EST POWER SUPPLY ._ .. MICROWAVE OVEN a. van. ovewsOaD . LEAKAGE DETECTOR 7 a Arno. co...,e,e I ' 944111:11 rO plc. .crmitt... k - 1 urr r1 ff *, li,il41 tl 11 11.4 E !ALE SCALE BEWARE FULL SCALE ETI PROJECT Completely passive proieCt receives micro- waves via an antenna which a (See ETI JULY 1982) ETI design suitable develops voltage for leadacld wet cells, across a detector diode meter. Output voltage - 13.8 Vdc. lead driving the Output acid gel electrolyte, vented nickel current - 7.5A Continuous Cadmium Monitor your mkrowave oven with this easy IOA Intermittent types and so on and so on. Electronics Australia Project, Tests Bipolar to build kit. All Components mount on Regulation- 0 to 7.5A : SOMV Unit Covers range single PCB, Transistors, Diodes. Fets. SCR's and PUT's. of 10.5v to 15v. including the meter. Save the expense of a mains powered rig. Determine battery Kit complete in every way. Excellent service aid for the hobbyist and condition instantly Genuine Hewlett Packard Hot Carrier Diode serviceman. Complete kit and instructions. Easy to Build! supplied. K3250 584.00 K 2525 $19.75 K 4326 $9.50 K1724 (still only) 514,50 FOR DESPATCH PEtP CHARGES AND ADDRESS DETAILS PLEASE REFER TO OUR AD. ON PAGE 93 ALTRONICS ALTRONICS ALTRONICS EA's BRILLIANT LABORATORY POWER SUPPLY e . l ra rfY t -t -r.. 505 SA LAB POWER SUPPLY TOUCH LAMP DIMMER HALF THE COST OF COMMERCIAL UNITS i Great new kit from EA. (April '83). Based on new Seimens IC S576A Light Dimmer IC. Instantly turn lamps on and off with just a light touch on a wall panel, or provide mood lighting z by touching the panel for a few seconds. i The Altronics Kit is complete in every way, including satin silver touch plates for that o See Ea May and June 1983 Specifications Input 240V 50Hz prestigous look. ce last we have had literally Over the 2 or 3 years Output Variable 2 - 50 V at up to 5 amps dozens of requests for a universal 5 amp Bench K6320 $19.50 Power Supply Kit. Naturally we passed this on to K3300 $139.50 Q the design team at Electronics Australia and at REMOTE CONTROL FOR K6320 last it is now a reality. Just look at the design 10 TURN VOLTAGE CONTROL OPTION concept) A fully mains transformer isolated This kit enables extra dimmer/switches to be : installed in conjunction with the Dimmer Kit. supply with a very clever "Switch Mode" low K3301 (ONLY). .$10.00 Includes satin silver touch plate. voltage circuit. HANDY + / - 12 V OPTION (SEE EA JULY 1982) Most Importantly it's dead easy to build (ours K6321 ONLY $9.00 worked first time)). K3302 $12.50 WHY PAY OVER $250 FOR AN INFERIOR COMMERCIAL UNIT? Q GO ANYWHERE 240V PWR. KITS c RADIOTELETYPE- See EA May and June 82. These great new Inverter kits enable you to power 240V appliances for your DECODER car, caravan or boat. (From Standard 12V COMPUTER car battery.) DESIGNED FOR J 40 WATT W THE MICROBEE Suits small appliances, i.e. turntable, tape deck, frequency APRIL '831 shaver etc. Vartabie adjustment z (SEE ETI enables accurate speed Control of turntable Display RTTY encoded messages on your VIDEO motors. Monitor. oc Simple circuit uses PLL TECHNIQUES, most W components mount on a single PLB simplifying Complete Kit includes D1 5 Plug for #5% Construction. IC connection to Microbee IN/OUT PORT. Sockets 1 aai K9733 $19.50 Provided W K6700 555.00 `MICROBEE'EPROM PROGRAMMER 300 WATT W VERSATILE. LOW COST 8 EASY TO BUILD Fully regulated and overload protected o Li I Great new project from ETI (Jan. 1983) All XTAL locked frequency. components mount on a single printed circuit E-. board. Unit simply plugs into the Microbee 1.0 port. Suitable for 2716. 2732, 2532. cc 2732A and 2764's Burn your games pro- NOW USING HIGH EFFICIENCY grammes and eliminate cassette loading times TRANSFORMER * Zero insertion force IC socket for eproms * Sockets for all other IC * 1 x 2716 sup- I- plied - get started straight away. * Kit sup- W plied in deluxe jiffy box, all mounting hardware Use to power hi-fi, TV sets and for 41i included lighting. K9668 $48.50 ct If you cannot afford a Video Monitor for your VIDEO RF MODULATOR computer this is the kit for you Super stable low modulation Q (SEE ETI OCT. 1981) oscillator design and very C.) distortion * Works with both B 8 W and Col- Y our TV Sets * Suitable for computers. TV 1 () what have ta-a.K SI` 1 games. TV pattern generators or e you Deluxe kit featuring heavy duty diecast _,o. z r7i i box for RF shielding * Input and output Q f sockets 7 " K9760 $17.50 LABORATORY POWER SUPPLY A Laboratory Supply requires specifi- cations second to none! 0-40 VOLT/5 AMP Output voltage 0-40 V, variable (SEE ETI MAY i JUNE 19831 Output current 0-0.5 A. variable limiting Gold plating on both PCB edge and edge variable limiting connector. 0-5-A, Low age rate parallel resonant XTAL used. Output regulation <50 mV at up to 2.5 A Sockets for all IC's. /H <100mVupto5A v Maximum output power .200 watts K6750 $199.50 Metering Voltage 0-40 V in 1 V divisions 510 DELIVERY ANYWHERE Current 0-0.5 A in 20 mA divisions IN AUSTRALIA! 0-5 A in 200 mA divisions ce Serles regulator design enables design and deve- All AltronIcs prices Include Sales Tax. lopment Of sensitive high gain audio and RP cir- cuitry free from hum and noise sometimes associ- Don't be conned by other advertisers ated with other techniques. whose seemingly low prices are "plus Tax In fine print". Q You could well pay up to 321/2% more. FEATURING: VARIABLE CURRENT LIMIT -DUAL METERING K3325 $175.00 FOR DESPATCH P&P CHARGES AND ADDRESS DETAILS PLEASE REFER TO OUR AD. ON PAGE 93 PpDOea 11E20 NOTCH OR SPOT AT THIS END 1 Since the amplifier is do coupled, a dc offset control has been included to enable the output dc level to be set to any voltage tpt ¢ ó required. b0 N N ts Y Y Y r O O In the ETI-166 Function Generator the N ;: .:;:°`Ñ`+ '--p output dc level is adjustable by means of a Io front panel potentiometer and this is ac- eit t-1 !' , do .~-` commodated using the optional offset EXT DC (c) "III input provided on the amplifier. OFFSET s r" If this is not required in a specific applica- INPUT (d) .4---- -N ` tion the on -board dc offset preset can be selected by fitting the appropriate link on 10 the pc board. Construction INPUT Construction is fairly simple using the ETI- EARTH (b) 1520 pc board layout. Since relatively high INPUT (a) frequencies are encountered, the layout POWER (i) and construction will affect performance. SUPPLY For this reason, an IC socket should not be GROUND !OUTPUT used. The pc board layout should not be altered unless you have access to the test equipment required to ensure that perform- ance has not been degraded. electrolytic Commence construction in the usual way by soldering the resistors and capacitors in place first. Be careful to orient C4 and C5 correctly since these are electrolytic band ( capacitors. Keep all lead lengths as short as possible. Solder the diodes, transistors and the IC in place, again ensuring that these devices are inserted with the correct orientation. Diodes Pin 1 of the IC is shown on the diagram accompanying the main circuit diagram. PARTS LIST-ETI-1520 A diagram showiñg the pinout of the included. transistors has also been The Resistors emitter of these devices is the pin closest to all 1/. W, 5% unless noted C7 1p ceramic R1 100k 08 10p ceramic the metal tag on the case of the device. R2 3k3 If the internal dc offset preset is to be R4 1k8 Semiconductors used solder this in place after bending the R5,R6 2k2 D1,D2 1N914 leads so that the preset will lie flush against R7,R8 2R7 ICI CA3100E the pc board. Fit a link as shown on the R9,R10 100R, 1/2 W 01 2N3866 component overaly to select the preset. RV 1 10k vert. mount trimpot 02 2N2905A Once all the components are soldered Capacitors correctly make a final check of the orienta- Miscellaneous CI 100n greencap ETI-1520 pc tion of all polarised components. If all is board; transistor heatsinks C2,C3 10n ceramic Thermalloy 2228B or similar (H needed). well connect a ±15 V supply and power up. C4,C5 47u/25 V single -ended Usually the dc offset will be required to be electro. Price estimate S12-515 zero to ensure maximum output signal level C6 3p3 ceramic and symmetrical clipping. Connect a volt- meter between the output and and earth to have low source impedances. rent. This value adjust the offset pot so that the do voltage may be insufficient if the The noise generators are therefore cap- supplies are extremely poor. In most cases on the output is zero. able of charging and discharging the filter The amplifier will work correctly on lower these resistors will be entirely unnecessary capacitors at the frequency of the noise. In- and should supply voltages than the ±15 V recom- only be used if a definite prob- creasing the value of the capacitors is usu- lem mended, except that slew rate and fre- exists. ally ineffective since a very large increase is In some applications it may quency response are decreased. The RCA be necessary usually required. to fit the output transistors with small data sheet includes a curve showing the rela- The only effective sólution is increase tionship to heatsinks. If, for example, the amplifier is between open -loop bandwidth and the source impedance of the noise gen- used supply voltage (see to drive a 50 ohm load at low fre- opposite page). The sup- erators, and this is best done by fitting quencies the instantaneous ply voltage should not be allowed to increase power dissipa- small value resistors in series with the sup- tion in the output will above ±15 V since this is the maximum vol- transistors be around ply lines. These resistors have not been 1 W and a small tage recommended for the op -amp. heatsink should be used. included on the pc board since the value The best way to determine if a If the is to be heatsink is amplifier operated from the required (if they are required at all) is de- required is to power up the unit same supply as other and check circuitry, ensure that termined entirely by the particular the temperature of the output transistors. the supply is reasonably free of noise. Al- application. The transistor cases should be kept at a though the amplifier has supply decoupling A good choice for most applications temperature that is comfortable to touch, capacitors on the pc board most devices would be around 3R3, producing only a 1 V and this will correspond to around 40 or 50 responsible for noise on supply lines tend drop at the maximum possible output cur- degrees Celsius. 74 - July 1983 ETI wildshand Pa songuII i:: «C ; p;. , .o ;:: ,mMIml'. .,rvnu c...C, ar 1 +u NIHgiñ,k, N HOW IT WORKS ETI-1520 n1` ' 11 -, I4--, 1 get 1 The project employs a wideband, high-speed of RV1 to R2. Thus, adjusting RV1 will adjust op -amp (IC1) operated from split supply rails, the output dc offset voltage. Capacitor Cl is a ' `i a followed by a unit gain emitter follower stage bypass for this input. NI f I .N1 (01, 02) that provides some output current Supply rail bypassing is provided by a 10n l :a gain so that the amplifier can drive low im- line, near on each I ceramic capacitor supply .III III I II I\\IN pedance loads. the op -amp, and a 47u electrolytic capacitor on The op -amp chosen is a CA3100. Input sig- each supply rail. nals are applied to its non -inverting input via terminal (a). R1 determines the overall input Performance. Open -loop gain versus fre- impedance. The output of the op -amp, pin 6, quency for the CA3100. drives the emitter follower output stage. As split supplies are used, a complementary pair of transistors is employed, 01 and 02. Diodes D1 and D2 maintain a potential of about 1.2 V between the bases of 01 and 02. As 6 IC1 pin of swings positive 01 turns INPUT lot further on and 02 turns further off and the output voltage goes toward' positive. As pin 6 INPUT lb) of IC1 swings negative, 02 turns further on, 01 EARTH turns further off, and the output voltage goes toward negative. DC OFFSET RV1 Resistors R5 and R6 provide a small amount ADJUST 10k of bias for the emitter follower stage, while resistors R7 and R8 ensure current sharing between 01 and 02. Resistors R9 and R10 establish the output impedance at 50 ohms. Overall feedback is provided by R4 and R3 the is EXT.DC and gain equal to: OFFSET INPUT tit POWER SUPPLY (R4 + R3)/R3 GROUND If you need to increase the gain, Increase R4. Capacitor C8 provides frequency compensa- tion in the main feedback loop. Capacitor C7 provides phase compensation for the op -amp for overall stability, while C6 provides a little AUSTRALIAN negative feedback at high frequencies to en- ECTOR CE) BROADCASTING COMMISSION sure high frequency stability. BASF D To provide Oc offset adjustment, a small o EMITTER bias voltage is, applied to the op -amp's invert- The ABC is an equal . ing input via R2. This can be obtaiñed on- ROT IOM vIERI opportunity employer board or off -board. 01 02 On -board dc offset Is provided by linking terminals (c) and (d). This connects the wiper BROADCASTING ENGINEERING OFFICER GRADE 1 The ABC has a vacancy in its Design and Development Laboratory for a Broadcast Engineering Officer to undertake investi- gations and projects involving minor design of equipment for Radio and TV broadcast- ing systems and facilities. Applicants must have the Electronics En- gineering Certificate (NSW) or equivalent and the Television Operators Certificate of Proficiency or equivalent, with at least six years' relevant experience in the mainten- ance of electronic equipment and a know- ledge of radio/television operational sys- tems. SALARY: $19,110-$21,260 p.a. Applications to Employment Officer (BH), ABC, GPO Box 487, Sydney, 2001. Mark envelope "Application - Confidential" and include details of qualifications and experi- ence, telephone number and copies of two recent testimonials or the names of two referees. Applications close Monday, 1st August, 1983. 52479 ETI July 1983 - -75 Digital Delay Line low cost hi fi 400ms VERSION That's right a 3 - WAY HI Fl speaker kit from only 519.9811 Each kit contains a massive 10" (250mm) woofer, cone midrange and DOME tweeter)) You also get, at no extra charge, the special cross- KIT over capacitors) The system is rated at approximately 20 watts RMS so it Is ideal as an economical but reasonably powerful main Hi Fi unit or as a second system for another room or outdoors. Each 3 -way kit comes with a recommended enclosure design which you can build yourself easily) You would normally pay well over 560 for the equivalent from major kit speaker suppliers so this is an Outstanding bargain. Sensitivity of EL.^. 3 system 93dB/lm/1 watt, Cat AK3700 ONLY . UNE HURRY LIMITED STOCKS and they are made in JAPAN)) 2 SETS (6 SPKR) 449 COMPLETE FOR STEREO The Digital Delay Line is designed to produce a huge variety of elect- IÍ ronic effects. It works very well but the amazing thing is the low, low ONLY $39.95 price) The effects depend on the time delay selected and some of those included are: Phasing, Flanging, Chorous, ADT (Automatic Double Tracking), Echo, and Vibrato. The delay time can be varied from 0.32ms to 1.6 seconds) Because the signal is stored In digital form there is, unlike analog systems, no degeneration of the signal with Woofer not to time and unlimited same scale repetition is provided by use of Freeze as the control. Other All the controls mount directly upon PCB's to eliminate wiring and to components further simplify construction the main board is 'plated -through' i.e. there are no wire links or link -through pins. The whole of the memory whether for the basic 400ms machine or the fully expanded 1.6 second PER model all fits on the main board. The cabinet, which is free standing but also suitable for 19" rack mounting, is fully finished to a very high standard. The panel is deep blue whilst the cover is sprayed with a durable black enamel. The kit is available right now from Jaycar at only 3-WAY SYSTEM $449 - compare that with inferior units that can cost over $2,00011 Cat KJ6621 $24.95 a set ONLY9998FROM SFF_ _1 $449 _ _ _ _ 8 - CHANNEL .P. ÉRsR 5()00 SERIES ONLY MIXER KIT OÑFR GRAPHIC 5299 110UALISI:II.S P Mp yI[o . n Po EQ. Black Monolith $319 ; ~AR 800?N` Oco S o 0 L11T l a o- - '` RES Ell SPECIFICATIONS IAIEMARCM 1911, S.nY IDS. F,.;arrÁ.e CAL at AMC ReyrKUl%IwB IMnR AI D.,lul.m IA.. 0 py,>\ MOO( SWITCM.STEREO "BLUEPRINT"' BALANCE CONTROL LINE FUNCTIONS OUT MONITOR OUT wIDCI BUY 2 AND SAVE $10 MONITOR VOLUME Ref: EA March/April 1983 AOP.a. 1"m... MOVING COIL INPUT CONTROL Ac c risv - ONLY 5389 MOVING MAGNET IOYNAMIC This great 8 channel 'live' mixer is perfect vaal. for 0..., CARTI I EATUR ES bands, churches, theatre groups, home AUSTRALIAN INOT MONG KONGI ALLME INPUTS17OFFI *EXTREMELY CLOSE TRACKING MADE - SPECIAL BUILT RACK K TS TONER INPUT TO RIAA PMONO EO recording, disco etc. CARNET OUALITYnE eawmso Each input channel accepts AUx INPUTS I? OFFI GOLD PLATED CONNECTORS either micro- CAL REAP. TAPE INPUTS 12 OM ON ALL INPUTS phone (balanced) or line (1V) levels. Power- INPUT LEVEL CONTROL ENGLISH 'LORLIN' LOW NOISE ful equalisation foldback effects facilities are TAPE OUTPUTS I2OFFl SELECTOR SWITCHES 540011, CALIBRATION provided. The LOW NOISE 1 SW,ip. METAL left and right master channels OSCILLATOR FILM RESISTORS USED can drive balanced or unbalanced lines with LED AVERAGE IVUI 8 PEAK TINNED FIBREGLASS PCB's 5 band "graphic" equalisation. "Blueprint" *LEVEL METERS 4808 TO 418 LOWCAPACITANCE SCREENED Separate CABLE USED THROUGHOUT foldback and "effects" are provided. OUALITY IC SOCKETS The can be SPECIAL REAR PANEL unit rack mounted or housed in a CAL RE 4.203 console chassis (which accommodates the 5000 preamp MULTICOLOURED RECTANGU EAR LED/USED power supply). Attractive wooden end - pieces finish the console to form a profes- si onal looking unit ONLY Complete 8 channel mixer t,,,,,KF..rIP y,. ' n s..--.,...... (19" rack mount) Cat. KJ6504 $495.00 : 5299 Console mount chassis, power supply and wooden tind pieces Cat. KJ6505 $98.00 L ' MULTICOLOURED You end up with a $1500+ unit for under $600 LED DISPLAY MULTI PURPOSE BOXES Amazing Value the We are proud to announce a great new range of DIRECT IMPORT all - ABS plastic cases for discerning CONSOLE BOXES with their electronics enthusiast. Quite frankly we are sick and tired of those black flimsy styrene boxes EACH UNIT HAS AN ALUMINIUM FRONT PANEL Aluminium lids. They split, they shatter and they look plain ORDINARY. SIZE -1611W) 0 96(D) 8 39(HF) n 571HRImm your small protects. Each boo h.n precision BLACK Shown below is a range of boxes that is going to revolutionise Cat. HB6200 - ORANGE Cat HB6201 - GREY Cat. 1106202 - BLUE Cat 1106203 - in bushes to take metal.thread fitting MOULDED lid (in the same colour as the boo) with moulded PRICE 1 UNITS ONLY 56.95 EACH: 10 OR MORE 56,45 EACH Most -9 countersunk screws. True quality. Naturally each box has slots formed ín the sides to take PCB's etc. SIZE 2151W) a 13010) x 471HF) x 731HRImm are available in 4 Beautiful colours - Black is one of rhemll - Cat HB6210 - ORANGE Cat. H86211 - GREY Cat. HB6212 - BLUE Cat-11E16213 - BLACK Shown also are 2 new sixes of die cast box. Note the sins. S11.95 EACH PRICE 1 -9 UNITS ONLY 512.95 EACH: 10 OR MORE SIZE - 105(W) x 143(D) x 321HF) x 561HR)mm Cat 1106220 - GREY Cat HB6221 - BLUE Cat -11136222 - BLACK MORE EACH PRICE 1 -9 UNITS ONLY 57.95 EACH; 10 OR 57.45 SIZE - 1701W) a 14310) x 321HF) a 58111R)mm Cat. H66230 - GREY Cat. 1106231 - BLUE Cat. HB6232 - BLACK PRICE 1 -9 UNITS ONLY S9.95 EACH: 10 OR MORE 59.45 EACH SIZE - 170(W) a 214)01 8 321HF) a 821HR)mm Cat. H66240 - GREY Cat H86241 - BLUE Cat. 1186242 - BLACK EACH PRICE 1 -9 UNITS ONLY 512.95 EACH; 10 OR MORE 511.95 RECTANGULAR BOXES SIZE - 1001 LI a 50(W) x 251D1mm Cat. 1186120 - ORANGE Cat. HB6121 - GREY Cat. H86122 - BLUE Cat. HB6123 - BLACK PRICE 1 -9 UNITS ONLY 53.95 EACH; 10 OR MORE 53.45 EACH SIZE - 112(L) x 62(W) x 3110)mm Cat HB6130 - ORANGE Cat HB6131 - GREY Cat. H86132 - BLUE Cat. HB6133 - BLACK MORE EACH PRICE 1 -9 UNITS ONLY 54.75 EACH: 10 OR 5425 SIZE 120)L) x 651W) x 401DImm - BLACK Cat. HB6140 - ORANGE Cat H86141 - GREY Cat. 1196142 - BLUE Cat. 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SYIINI Y 7000 Patented clip to cod Imng fie` Robust the cast case POST AND PACKING CHARGES F u0y waterproof 155 59.99 151.501 510 574.99153.201 ScC- Protected Iro m the hobble environment of $25 149.99 154.501 $50 699.99156.501 the engine compartment 5100 ex more 158.001 elGr- Mail Order By SAVE $10 SHOP HOURS CARL INGF ORD Mon Fri 9an 530pii: Sat 9an lbain: lhurs night 8301.1 BANKCARD SHOP HOURS SYDNEY ONLY $89 night 8-30pm Mori F re 8.30rn 5.34mr: Sat 8.30.en 17pm: Thum Via Your Phon prolsoR 1E1 4. A general purpose IC audio amplifier module This is an ideal project for the beginner. In fact, most constructors will find it handy to have at least one around. A general purpose small audio amplifier finds many useful applications. Just two described here are an intercom and a 'baby minder'. Geoff Nicholls A VERY USEFUL object for any electronics Where the full power output capability of room as shown later in enthusiast to have around is a - this article, or you simple audio the '380 may be used, copper shim or tinplate can make a simple intercom which amplifier. It can be used to test the operation heatsink - is also 'flags' are soldered to these pins to illustrated later. Another article in this is- of many circuits or employed in some practi- get rid of more heat and keep the tempera- sue shows how to use the module in a cal item of equipment-such as an intercom. ture of the IC down. This loudhailer. simple, yet versatile, module is easy The '380 has a gain of 50 times. is, to That it Right, let's get down to the business of construct and can be powered from a vari- will amplify the input signal level by 50, ety of building it. supply voltages, depending on your which is a gain of 34 decibels (34 dB). That is: application. It will drive loudspeakers of 4, 8 or 16 ohms impedance and can deliver a Gain in dB = 20 log10 (50) Construction maximum output of five watts. =20x1.7 The project has As you can see from the overlay and wiring been designed around an = 34 dB. diagrams, integrated circuit audio power amplifier, the there's very little to it. Start with LM380 (from National the pc board. Whether you've made your own Semiconductor) or The gain of the '380 is fixed by the man- or the uA380 (from purchased one, just give it a quick check - Fairchild). This is quite a ufacturer. But what if you want a volume over to versatile little IC and, using make sure all the holes are drilled it, an audio control, as is so often necessary on an audio correctly, that amplifier is very simple indeed to make. there are no small copper amplifier? That can be simply arranged by 'bridges' between closely spaced The '380 is generally available in a 14 -pin connecting a tracks potentiometer as a voltage di- (particularly between the IC pins) dual -in -line package, and this is what I have vider to and no the input of the IC. You can see how tiny cracks in any tracks. It's unlikely employed here. An 8 -pin version is available, that's done from the you'll circuit and construction have trouble, but it's always a good idea but cannot be used in the pc board I have diagrams. to designed for this check, before you run into trouble! project. Pins 3, 4 and 5 plus You can use this project to amplify the Note 10, 11 and 12 of the 14 -pin package that mounting holes are located at are all output of a crystal set or one -transistor re- either end of the connected together by a copper bar inside the board. These should be ceiver to loudspeaker level simply by con- drilled to a 4 '380 package, on which the chip is suit BA bolt, or whatever size mounted. necting the output directly to the input of the you are using. These pins can be soldered to a large area of module. You can commence assembling the board copper on the pc board to act as a heatsink in You can make a 'baby minder'- for keep- by soldering resistor R1 in place, followed by relatively low power applications. ing an ear on the baby in its cot, from another capacitors C2, C3 and C4. All components 78 - July 1983 ETI OC amp modula C3 HOW IT WORKS - ETI-464 C2 100n 100n Cl There's not much you can say about thisi The C5 whole lob Is done by the '380 IC audio power SW1 14 100u amplifier. The input is coupled to the '380 via a 16 u INPUT 1/ + 16V 16Vor25V capacitor (C3) and the volume control, RV1. IOU The latter is Just a voltage divider, applying 1 R1 LOUDSPEAKER less or more voltage to the IC's input as the BATTERY (SEE TEXT) 2R7 8 OHM potentiometer is varied, thus varying the volume. The output of IC1, pin 8, Is biased at half the 3,4.5,7 C4 Z supply rail (e.g: it will be at 4.5 V if the supply is 10,11,12 =100n 9 V). For this reason, the output is capacitively coupled to the loudspeaker via a large value electrolytic capacitor, C5. This presents a low mount on the non -copper side of the board. volume control and an on/off switch are also impedance in series with the loudspeaker, and negative leads provided with the overlay diagram. Note which Is a relatively low impedance device. Next identify the positive Any tendency to instability of the amplifier is of the two electrolytic capacitors. These are that the input lead should be run in shielded needs suppressed by the network of R1 -C4 con- 'polarised' devices and can only go in one cable, in general, especially íf thís lead nected from the output to common. way. Solder them in place, putting the posi- to be more than 300 mm or so long. This The supply rail is bypassed by an electro- tive lead of each in the hole marked with a'+' prevents hum pickup from house mains wir- lytic capacitor, Cl, at the low frequencies, and on the overlay diagram. ing. For short runs, a pair of tightly twisted a greencap or ceramic capacitor, C2, at the The '380 IC can be soldered in place next. hookup wires will suffice. higher audio frequencies. Make sure you place it in the board the right This module will drive any size loud- Note that provision has been made on the pc board for powering an electret type micro- way round before soldering the pins. Do not speaker, from the tiny 50 mm 'transistor radio' types to 400 mm diameter 'monsters'. phone, simply by adding a resistor adjacent to use an IC socket as the board is designed to C3. act parially as a heatsink and pins 3, 4, 5, 10, In fact, the larger a loudspeaker, the more 11 and 12 must be soldered to the copper area sensitive it's likely to be and the louder it for this purpose. will sound! You don't need more power to The heatsink flags can be constructed next drive a larger loudspeaker, despite what you if you need to use them. Use heavy gauge might at first think. copper 'shim' or tinplate sheet (obtainable at The bigger loudspeakers generally have a hardware and motor spares stores). Two are more powerful magnet than the smaller required and the dimensions and cutting de- types. This makes them more sensitive to the tails are shown in the accompanying currents flowing in the voice coil. This and diagram. the larger cone combine to produce a louder COMPONENT PINOUTS General details for wiring up the speaker sound. Capacitors tantaluma electrolytic VOLUME RV I0k y C2 SW1 TO + POWER SUPPLY 1000u S HIELDED CABLE TO INPUT PARTS LIST- ETI-464 Overlay and wiring diagram. Showing component placement and general wiring details. Resistors all Y or 1 W/5% R1 2R7 RV1 10k log. pot. Capacitors vOLUME Cl 1000u/16 VW or 25 VW RV I FIB electro. C2,C4 100n ceramic bypass C3 100n greencap SWI C HEATSINK C5 100u/16 VW RB electro. FLAGS CS Semiconductors TO POWER 1 IC1 LM380 SUPPLY TO C2 ICI C3 SPEAKER Miscellaneous r Q ETI-464 pc board; SPST switch; shielded cable; wire, etc. Price estimate S7 -S8 Side view. Showing assembly of the heatsink flags. ETI July 1983 - 79 pTcAsell (AZ Testing it LM380 audio power amplifier features The easiest way to test it is simply to connect Wide a 9 V battery to the module and turn up the general description supply voltage range volume control. Then, touch your finger to Voltage gain fixed at 50 The LM380 is a power audio amplifier the 'top' end of the volume control the for con- High peak current capability - sumer application. In order to hold system cost to right hand lug when looking at Input referenced to GND the rear of a minimum, gain is internally fixed the pot. You should hear hum at 34 dB. A and noise, or unique input stage allows inputs to be High input impedance perhaps a loud ground 'blurting' sound. If not, check referenced. The output is automatically self ent- Low distortion that the battery is connected the right way ering to one half the supply voltage. Quiescent output voltage is at one-half of the round and that the speaker and volume con- supply voltage trol wires are all intact The output is short circuit proof with internal and correct. Check Standard dual -in -line package that you have the IC correctly orientated. thermal limiting. The package outline is standard dual -in -line. A copper lead frame is used with the Connecting a 9 V battery in reverse to the Device Dissipation vs Ambient Temperature center three pins on either side comprising a heat module is unlikely to destroy the IC, 12.0 but any sink. This makes the device easy to use in standard higher I supply voltage connected in reverse p -c layout. INrINITl NE1AT SINK 17C10 sure will, so watch this point. 10.0 Uses include If the amplifier tends to be unstable, simple phonograph amplifiers, inter - corns, line drivers, teaching machine outputs, 'squealing' or otherwise 'acting up', try con- 8.0 alarms, ultrasonic drivers, TV sound systems, AM - necting a 4u7/16 V tantalum capacitor be- SPIV NV1COMta EatLN 10'C41 FM radio, small servo drivers, power converters,etc. SO IN COMO POP PC SOARO 3S'GIS tween pin 1 of the IC and the adjacent 6.0 4s01N CoWtn COIL PC So CO L'UW grounded area afthe pc board, 2 SO IN COPnR run PC 104110 45'C N directly on the 0S IN COP FR FOIL PC oAllo. 11 23't a underside of the board. The positive lead erran 14 V, 4.0 goes to pin 1. Keep the lead lengths short. NON INVERTING INPUT I 11 NC This should cure it. Always t1 2.0 IIIIIC keep the amplifier's input leads IPIIaIR pot* away from the speaker leads, to avoid UNO 4 n feedback which may result in 'howl round'- la 0 10 20 30 40 50 60 70 80 an uncomfortable INVINIING INPUT S whistling or howling TA -AMBIENT sound that is TEMPERATURE (°C) affected by moving the leads. GNO 1 Power supplies 'NanN P.n. Total Harmonic Distortion This module can be powered form batteries, a vs Output Power 10 suitable plugpack or rec- transformer and absolute maximum ratings ó 1.0 1 1111t INI tifier to suit yourself. The power output de- Vcc 22V IIIII Supply Voltage 22V Fe 10 R, Ea pends on the supply voltage 5 and the speaker Peak Current 1.3A TO CNN.II F impedance. As stated earlier, the '380 can HEATSINA 1150 Package Dissipation 14 -Pin DIP (Notes 6 and 7) 10W 50 COPPER WINGS drive 4, 8 or 16 ohm speakers. By far the Input Voltage í0.5V I so better speaker to use is an 8 ohm impedance Storage Temperature _ 40 III -65°C to +150°C : type. Fortunately, they're also the most com- Operating Temperature 0°C to +70°C MI1IIIII 1ul 11111§11II mon MIIIIH111111111111NIH type. Junction Temperature +150°C Powered from a nine volt will Lead Temperature 10 10 1111 Ha 111111 battery, you (Soldering, sec) +300°C 0 -fiU1111fi!!ulll) get about half a watt (500 mW) output, which is more than adequate for 'personal' 1.t 12 OS ID 20 SO 10 listening stations; e.g: providing loud- electrical characteristics Po - OUTPUT POWER (WATTS) Note 1: VS 18V and TA 25"C unless otherwise specified. speaker output from a crystal set or one - PARAMETER SYMBOL transistor radio, etc. The power dissipated by CONDITIONS MIN TYP MAX UNITS the IC under these circumstances is about Power Output ROL/TIMMS' three quarters of a watt maximum, so no RL 852, THD 3% 2.5 W heatsink flags Gain Ay would be necessary. The mod- 40 50 60 V,V ule draws only about 5 mA with no signal Output Voltage Swing VouT RL ' 812 (called the 'quiescent current'). 14 V°O Input Resistance Z1,, The absolute maximum supply voltage the 150k 00 Total Harmonic Distortion THD IC will tolerate is 22 V. With an 8 ohm 0.2 % speaker, the project will deliver five watts Power Supply Resection Ratio PSRR dB output, which is remarkably 38 loud! Under Supply Voltage Vs these circumstances, the power dissipated by 8 22 V Bandwidth BW the '380 will be a little over three watts max- Poo, 2w, RL - 80 100k Hz imum Quiescent Supply Current 10 and heatsink flags will definitely be 2 25 mA necessary. The quiescent current is about Quiescent Output Voltage VOUTo 8 mA on a 22 V supply. 8 9.0 10 V Bias Current ¡BIAS A plugpack or transformer and rectifier Inputs Floating 100 nA supply Short Circuit Current lac suitable for powering this module 1.3 A should provide 12 Vdc at 200 mA or so. Us- Device ing such a supply, the project will deliver Dissipation vs Output Device D'ssipat,on vs Output Device Dissipation vs Output Power 403 about one to 1142 watts - Load Power - 802 Load Power - 160 Load to an eight ohm 3.s 3.5 I 3% DIST 35 speaker, which is I I quite suitable for an in- i1 LEVEL 3,0 1_ 1 tercom, for example. The heatsink flags are 30 LS C i 3* DIST. not entirely 1.5 . necessary with this sort of appli- 15 wmpm. LEVEL / cation, especially in an intercom where the `s 20 LO ó 2-0 '1'-r- amplifier is 14 +aV' 1- only used intermittently. 1.5 1 . 1.5 12V / / 18 Two nine volt r -10Y-CY-+ I 1.5 _ -, batteries connected in series 14 -'10V DIST. y # I 4 3ti DIST. ó 1.0 will supply 18 Vdc or so to the module, which 1,0 -9V - 1,0 - ; t1 - 10% Cit.11111"a....LEVEL JIr.-` 1 LEVEL o 12 will deliver about three watts to an 8 ohm 0s f 0-5 as speaker. Heatsink flags are necessary in t 54-_ c fi Dtsr. T - this 1 0 1I I 10`LEVEI , - case. Note when 0 r I I 1 that, using a 4 ohm speaker, 05 1.0 - 15 2.0 15 3.0 3.5 4A 051.0 1.0 2.0213.03.54.04.55.0 051.0 I5 20 25 3.0 35 4.0455.0 the supply should not OUTPUT POWER (WATTS) exceed 15 volts. OUTPUT POWER (WATTS) OUTPUT POWER (WATTS) 80 - July 1983 ETI OC A 'baby minder' You can 'keep an ear' on a baby asleep (or supposed to be!) in its cot in another room by 22 some sort microphone pick HEATSINK (TWO REQUIRED) TO BE organising of to ATTACHED TO EITHER SIDE up sounds from the baby's room to be amp- OF IC AS SHOWN IN MAIN PICTURE. lified and heard in another room. ALL DIMENSIONS IN mm The general wiring diagram for a baby minder is shown in Figure 1. Here, a small 8 ohm loudspeaker is employed as a 25 microphone - and they're remarkably effec- tive. A transformer is needed to 'step up' the tiny voltages produced by the speaker - VOLUME microphone. A suitable type is generally de- scribed as a `transistor output transformer, 1k centre -tapped to 8 ohm'. Dick Smith Electronics lists a suitable type - cat. no. OUTPUT M-0216. Altronics have a similar one. Tandy ETI-464 AMPLIFIER lists one also, no. 273-1380. MODULE The '8 ohm' side is connected to the INPUT -microphone is side with GND speaker - this the POWER SUPPLY GND 1k just two leads. The side of the transformer 50 mm 8 OHM is connected to the input of the module. SPEAKER Mount the transformer close to the module. TRANFORMER r - M-0216 OR SIMILAR The module could be mounted in a suitable BOTTOM VIEW cabinet with the speaker, volume controls and on/off switch mounted on the front. I The speaker -microphone could be mount- ed in a small jiffy box placed in a convenient I "TWISTED PAIR OR position in the baby's room, near the cot. This I FIGURE.8 CABLE to amplifier via a length of connects the A 'baby minder'. This is pretty simple to arrange. A 'transistor 'twisted pair' cable or light 'figure -8' flex. Try 50mm 8 OHM output transformer is used as a step-up transformer for the small SPEAKER and avoid running this lead adjacent to 8 ohm speaker used as a microphone (they're cheap and effective). house mains wiring to avoid possible hum BABY PICKUP pickup. I have specified an 8 ohm speaker as a microphone as it is of such a low impedance Intercom. A transistor output here too be- of hum pickup on the transformer is used that the possibility cause the loudspeakers at each cable between the microphone and the amp- Station' of the Intercom double lifier is greatly reduced. as microphones. You can either use a battery supply or a POWER + 12 Vdc plugpack. SUPPLY Intercom TRANSFORMER The general details for wiring a simple in- M-0216 tercom are shown in Figure 2. You'll need OR SIMILAR REMOTE STATION two single -pole, double -throw (SPDT) toggle BOTTOM VIEW r switches with a spring return. Double -pole 50mm 8 OHM types are also suitable, just use one side (e.g: SPEAKER C&K type 7208 or similar). You'll also need an M-0216 transformer, or similar, as for the SPRING Figure 1 circuit. RETURN SWITCH Two small 8 ohm speakers are used as both and microphone at each end of the speaker TALK intercom. SWITCH TALK A volume control is necessary on an in- tercom and a small 'trimpot' can be mounted SPRING on the pc board where the volume control RETURN connections are made. The hole spacings are CABLE suitably placed for soldering a common verti- cal mounting trimpot in place. Use on of the Printed circuit artwork. Full-size reproduction of the pc board layout. same value - i.e: 10k. Test out the intercom and set the volume control to suit yourself. A suitable cable can be made by twisting together three strands of light hookup 'wire eti or buying a suitable length of light multicore 464 cable. Note how the various common, or earth, connections are made to the one ground point on the pc board. Conclusion Well, I've described how to build yourself a 'l. general purpose audio amp module and ho« to use it in a couple of applications- the rest is up to you. Have fun! ETI July 1983 - 81 ALTRONICS ' ALTRONICS ALTRONICS ALTRONICS V 4111111L. z O 1 tr Dear Customer its midwinter again Igroanl - every July our sales have been lousy as It seem all the electronic enthusiasts In Australia would rather sit around a nice warm fire than' tinker with Electronics. This year, to make It even worse we've expanded our overnight mall order service section by around 400%. So we simply can't afford another Slow July - hence you reap the benefit of all the exciting Altronlcs quality direct Import components and products advertised throughout this magazine. 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Great for picking up small screws, pins, nuts, washers, resistors, etc. Also can be $7.95 used for holding items In place. $3.95 prolcI teE Ta ra, ta ra .. . the ETI loudhailer: Build this loudhailer and make yourself heard at rallies, picnics or sporting events. Using the ETI-464 General Purpose Amp. Module mounted in the back of a locally available horn speaker, it's simple to build and quite effective. Geoff Nicholls PROJECTING your voice outdoors is quite horn itself is essentially an impedance a difficult task without some means of 'di- transforming device which increases the recting' your voice and amplifying it. Gener- acoustic loading on the driving diaphragm ally, you'll want to address a group of to allow better 'matching' to the air. The people located some distance away, or a throat area of the horn increases exponen- group of people spread out in front of you tially as you move away from the driver. for some distance. If you can direct your The horn may be straight, as shown in voice over a narrow 'beam', then less of the Figure 1, or folded, as shown in Figure 2. sound you make is wasted. The folded horn is physically smaller and is The old-fashioned megaphone did that the most common type in low cost PA job before 'electronics' entered the picture. systems. Folding the horn reduces the effi- Outdoor public address systems came into ciency slightly but increases the coverage being with the advent of valves. For many or dispersion, which is usually an advan- years PA systems were cumbersome, tage. hardly portable beasts until minaturisation The straight horn has a long 'throw' and is came along post World War II. The first useful for narrow sound coverage at grea- 'loudhailer' PA systems portable by one ter distances, but is more cumbersome, person used miniature valves, a small horn especially for handheld applications! speaker and a set of cumbersome, heavy batteries that didn't last all that long. The project When power transistors came along, loudhailers proliferated. They could be held For our loudhailer, we had to search around in one hand, used a small number of'torch' for a suitable small folded horn. There is a batteries and did the job better than before. variety available and prices vary widely. Probably the most common are 130 mm diameter (5") low power folded (or 'reflex') The horn speaker horns generally sold for boat or CB PA use. The horn loudspeaker is by far the best type Rectangular folded horns are also avail- for outdoor use. Horns can be made weath- able, having an opening of 200 mm wide by erproof and have an efficiency of better 120 mm or so high. than 20% compared to a few per cent for Efficiencies vary widely and are best ordinary speakers. This allows an amplifier judged by the weight! Drivers with larger, Your shout! Not beautiful, but effective. of lower power to be used, with consequent heavier magnets are more efficient than sayings in power consumption, physical those with smaller, lighter magnets. Most The horn we chose for our prototype is size and weight. have a 'dispersion angle' - the angle over imported and marketed by Benelec Pty Ltd, Horns are intrinsically limited in their fre- which the majority of sound is dispersed model no. 8-224. It is a 130 mm diameter quency response, and their efficiency is in- .from the horn - of between 60° and 90°. folded horn, measuring 170 mm long over- versely proportional to their bandwidth. PA The narrower the dispersion angle, the all. There is a cover on the rear of the horn horns are designed to operate over the greater sound level you get at a given dist- with plenty of room inside to mount the voice band at maximum efficiency. The ance from the speaker. power amp. module. It has a mounting DRIVER MOUTH THROAT I-r- r-¡'---_r_ .. Figure 2. A folded horn is physically smaller Figure 1. A straight horn has the width of the throat growing exponentially larger with than the straight horn and has increased increasing distance from the driver. dispersion. ETI July 1983 - 85 prtopc/ teg bracket that allows the horn to be swivelled over a wide range of angles. It is available C2 with driver impedances of 4 ohms or 100n 14 C5 8 ohms, though the latter is best in this ap- P81 1000u 8 + 100u plication. The dispersion angle is quoted as ELECTRET t M1C 60°, which we saw as desirable, and the T output is quoted as being 122 dB (presum- R1 BATTERY 2R7 ably with 1 W drive at one metre). It weighs is yet 1.15 kg, which not too heavy, ensures 3,4,5,7 C4 i HORN the sort of driver efficiency desirable for Circuit. Resistor R2 is added to the ETI-464 10,11,12 100n LOUDSPEAKER maximum effectiveness. I module to provide bias for the electret micro- phone. I Using this horn, and constructing the loudhailer as described here, you can make yourself heard at 100 metres. If you don't P81 need that much throw, then a lower cost, less efficient horn will suffice, but construc- tion details will have to be worked out to suit yourself. See Shoparound in this issue for horn suppliers. CI An electret microphone insert was em- TO TO BATTERY HORN ployed to make a microphone. It proved SPEAKER cheap and effective. To provide a handle and battery case, a short length of 50 mm TO ELECTRET (i.d.) PVC water pipe was used, along with MIC two end caps. This mounts, via one end cap, on the horn's mounting bracket and Overlay and wiring diagram. board batteries are slipped inside. A Showing the assembly and external wiring. RV1 momentary action pushbutton switch, mounted on the 'handle', serves as an on/ off switch. REAR VIEW Originally, I tried mounting the mic insert DIN SOCKET REAR VIEW in the of the horn's rear cover, but DIN PLUG centre MIC INSERT feedback proved a problem and I couldn't utilise the full gain and output of the amp- SHELL mum supply voltage you can use is 14 V SHIELD lifier module. A little experimentation WCONNECTION solved the feedback problem and improved without exceeding the '380's dissipation an operator's visibility at the same time. rating, and you only get three watts' output. I mounted the mic insert in a DIN plug In a loudhailer, every watt counts. which plugs into a socket mounted at the Hence, I opted to use an 18 V supply. PARTS LIST-ETI-465 top of the horn's rear cover. I also mounted There are two ways you can arrange this a gain control pot on the cover. These mea- with batteries. Two no. 2362 9 V batteries This requires construction of the ETI-464 amp. sures overcame feedback problems and al- can be 'snapped' in series. These are 75 mm module with the addition of the following com- ponents: lowed you to see over the top of the horn. long with a male snap clip at the positive The maximum output a '380 will deliver is and a female snap clip at the negative end R2 2k2, Y. W/5% five watts into an 8 ohm load using a 20 V end. Alternatively, you can use 12 AA cells RV1 10k/C panel mount pot. supply. With an 18 V supply, the '380 will mounted in three four -cell battery holders. Electret mic. insert (e.g: D.S.E. no. C-1160); 5 -pin deliver a maximum of four watts (@ 10' There are two advantages to the latter: the DIN plug and socket; knob; horn loudspeaker - distortion - which is tolerable) into an batteries last longer and the whole assem- Benelec no. 8-224 8 ohm (see text); three 4 -cell 8 ohm load. With a 4 ohm load the maxi - bly is considerably cheaper. AA battery holders and clips plus 12 x AA bat- teries or 2 x 2362 9 V batteries and snap clips; DPDT momentary action pushbutton (e.g: D.S.E. no. C-1220); length cr 50 mm PVC pipe and two end caps; wire, etc. Price estimate S45 -S50 Construction Putting the loudhailer together is quite straightforward. The ETI-464 pc board has mounting holes which match the mounting posts on the inside of the 8-224 horn speak- .\ er's rear cover. Self-tapping screws are used to mount the board and the mounting holes should be drilled to size before as- sembling the components to the pc board. Assemble the power amp module accord- ing to the instructions given in the previous article on the ETI-464. Note that R2 has to be added, as shown on the overlay diagram. Don't attach any wires yet until the mechan- ical assembly has been completed. Drill the mounting holes for the volume Insides out. The amplifier board mounts inside the rear cover of the Benelec 8-224 horn. pot and the DIN socket in the speaker's rear 86 - July 1983 ETI _0uzfinslaigir ELECTRONIC .._COTTON HOBBYIST! WOOL WAD TINNED / DO YOU LIVE IN ... COPPER WIRE ELECTRET MIC. INSERT Making the microphone. A DIN plug is modified as shown to house the electret mic insert. Ringwood Lilydale Boronía Battery holder wiring. If you use a dozen AA cells, as I did, this Is how the battery holders are wired up to provide 18 volts. cover. The DIN socket goes at the top, the volume pot at the bottom. Also drill a hole in the bottom lip of the cover so that the leads Wantirna from the battery may be passed through. Now tackle the handle/battery compart- ment. Cut a 200 mm length of 50 mm i.d. CI PVC pipe. File the ends smooth and square .a and slip the end caps on. Holding them in place with masking tape, drill holes on either side, right through the cap and pipe, Bayswater so that self-tapping ('PK') screws can be used to secure the end caps in place. Drill these holes to the root diameter of the PK screws. Remove the end caps and enlarge the to holes to the appropriate clearance diameter Croydon for the PK screws. Drill holes in one end cap to suit the speaker mounting bracket and to pass the battery leads. Bolt it in place. Now take the tube and mark a hole posi- tion at the 'top' end for the on/off pushbut- Mooroolbark ton switch. It should be located such that it clears the upper end cap, yet is not too far down the tube so that access to the switch connections is restricted. Now wire up all the battery connectors, the pushbutton switch, the DIN socket, the etc.... volume pot, the speaker and the pc board. Check it all carefully when finished, then Rear view. The mic plugs Into the DIN socket at the screw it all together. A little wad of sponge op. The volume control is below it. The 'handle' We carry a comprehensive rubber in the upper end of the handle sec- houses the batteries. ures the batteries. range of electronic Now you can make the microphone. The and say a few words. No 'howl round' components at very keen basic assembly is shown in the accom- feedback or 'ringing' should be experi- prices. panying diagram. We found that angling the enced, except perhaps if you're in a small mic insert down (when the unit is plugged room. Best try the unit outdoors. in) helped reduce feedback problems and a Adjust the setting of the volume control tendency to 'breath i Hess'. for maximum output without feedback or The accompanying photographs 'show ringing being evident. Always speak very Iah.J. ,TRUSCOTT the internal and overall assembly, when close to the microphone. completed. If you wish, it may be convenient in some ELECTRONICS applications to have a 'remote' microphone. CE 1R EASTFIELD Using it An electret insert can be readily installed in a CB -type handheld mic case, with the ° & BAYSWATER ROADS, For an initial try -out, set the volume pot push -to -talk switch wired in parallel with SOUTH CROYDON, VIC. about halfway advanced, plug in the the loudhailer's on/off pushbutton via the microphone, position your mouth about DIN plug and socket. TELEPHOJE (03) 723 3860 10 mm or so from the mic, press the button Happy hailing! ETI July 1983 - 87 Quartz IEC Cable á oheapo Li113900ii That's right, a pin -for -pin equivalent to the popular Connectors LM3900 for only 25 cents! We have heaps of LM Crystal 3401 (made by National Semiconductors). 14 pin plastic DIL IC's. The LM3900 normally sells for Clock around a Dollar. NOW you can have 4 for a Dollar! .64(9 (Minimum buy 4 pieces) enient Cat ZL3901 5:;# Quad OP -amp in a 14 pin DIL package - 4I ONLY 25 cents each Most imported equipment these days now uses IEC-320 style AC power inlet connectors. Indeed, 4 the electronics mays will soon be specifying these connectors on many of their mains -powered projects White LEDs' to simplify (and therefore make safer) mains wiring. No not really. Just white diffused. When not lit up Jaycar now stocks a range of ELECTRICITY AUTH- they look milky white. When lit up they look just ORITY APPROVED mains line cords. like an ordinary 5mm red LED. We have them in straight entry, left and right entry We don't get much of a call for them so out they go. with and without standard 240V mains moulded Normally 50.15 each. July only 50.10 each. Mini plug. Each cord is a generous 2 metres long and is mum buy 51.00 worth. This represents a 1/3 saving rated at 7.5 amp continuous. They are only available off normal. in grey. (minimum buy 10 pieces) wai Cat. No Description Price Cat 201708 PS4302 LINE CORD STRAIGHT ENTRY -2M 53.95 10 CENTS EACH PS4304 LINE CORD R/HAND Cat XC6000 ENTRY -2M $3.95 495 PS4305 LINE CORD L/HAND EA freezer alarm - Very compact and reliable ENTRY -2M $3.95 Piezo Audio Indicator has strong - Self-starting one -second stepping motor PS4306 LINE CORD STRAIGHT We have the piezo audio alarm for this project Small WITH PLUG- 2M S4.95 torque ENTRY 240V loud and low cost. Powered 1.5V AA battery that lasts for a year PP2302 IEC 320 CHASSIS PLUG $2.95 - by Cat AB3440 - Supplied with two sets of hands, one short one long -1.15 second/month accuracy - 56mm square, 15mm deep. BT151- 650R Complete with data sheet, instructions and wall This is the 650 volt version (for extra safety) of the hanger bracket. C122E SCR which we use in the popular 'Fluor- escent Lamp Starter' Kit as described in October 1982 EA. Normally $1.50 each. This month only ETI 733 RTTY $0.95 each! (Minimum 5 pieces). Makes the Fluoro starter kit very cheap! converter (PCB's for the kit) Cat. HP8747 ONLY 51.95 mos EORY Cat. ZX7022 One of the most popular recent kits. We have had trouble keeping up with .the demand for this one DATABY FAIRCHILD but now we have adequate stocks. 230 x 175mm gives full data on Use this device with your Communications Receiver This book measuring and Microbeee to watch the teletype newswire popular RA J1 and EPROMs (2102, 2114, 4116, amp 650V SCR) services from around the world! (8 4164, 2708, 2732, 2764 etc) as well as many other This short form kit contains PCB, 15 pin 'D' con- lesser .known types including shift registers etc. nector, all board components, centre zero tuning Due to industry standardisation, the data in this book meter. 6116 RAM will relate to other manufacturers of MOS memory This is an amazingly low price project for what you with the standard part numbers. getl! 6116-3 RAM is scarce at the moment but we scheduled and it has arrived. At a new low Ref: ETI April 1983 our stock orders A price tool! BULK BUY WE HAVE THEM... BARGAIN AT WERE $12.50 NOW $9.95 Cat BF4710 10 up $8.95 Cat. 228430 $ 3 95 Cat. KE4654 H A prolessionally.engineered electronic ("breakerless") contact breaker system. Ves, only Jaycar has a complete Hall -effect triggerhead assembly designed to adapt to an extensive number of can Each kit contains the following: - HALL EFFECT TRIGGER HEAD - MAGNETIC ROTORS FOR BOTH 4 & 6 CYLINDER CARS OVER 6 CAM LOBE ADAPTORS -- -distributor cap OVER A DOZEN ADAPTOR DIFFERENT PLATES FOR YOUR PARTICULAR DISTRIBUTOR OTHER HARDWARE (i.e. SCREWS etc.) YOU CAN REMOVE THIS SYSTEM AND RE -EQUIP YOUR CAR WITH THE ORIGINAL BREAKER POINTS WHEN YOU SELL THE CART AS EASY TO INSTALL AS A SET OF POINTS! - INSTRUCTIONS (SIMPLETO.FOLLOW) INCLUDED! This set is designed to fit most European and Japanese cars. In fact it will also fit many Australian cars fitted with Lucas. Bosch, Motorcraft AC Delco or Autolite electrics. I/ you wish to check first- please send SAE for carldistribu for list Because we have no way of knowing, you get the fitting set for ALL of the distributors available. Basically you end up with a par full of parts that you don't need to use) (Perhaps for your next car7) Quite frankly, we are amazed that we can supply such a comprehensive kit for this price. To produce a kit that will adapt to the dozens of different distributors around is amazing) Remember, once you have installed a breakerless system it will never wear at and that part of your system - rotor arm will remain in tune FOR EVER. We expect this kit to sell well. To ensure that you receive one, check with us early) Cat KJ6655 SHOW YOU 1.1; -trigger head AUSTRALIA" TO spacers IN "ELECTRONICS ASSISTS_adapter 96 WATCH FOR NEWS THIS HOW TO ADAPT plate IMO magnetic rotor ` ø_------C3) -cam adapter distributor cam Magnificent 80 Character/Second Matrix Printer) - WITH GRAPHICS CAPABILITY. INCREDIBLE PRICE BREAKTHROUGH)) We DARE you to compare with Other units selling for well over $90011 WHERE ELSE will you buy an 80 column (142 compressed mode) printer for under 57007 Check the specs below and you must agree!) QUALITY VERO BOARD* FUNCTIONAL SPECIFICATIONS MATRIX BOARD!!! Printing method: Serial impact dot matrix Printing format: Alpha -numeric -7 a 8 in 8 x 9 dot matrix field At last Back in stock the ORIGINAL matrix board. Each board measures a generous Semi.graphic (character graphic) . 7 x 8 dot matrix 93 x 127mm )3%"x5") and has hundreds Of 1.0mm holes on a 0.1" grid. The board Bit image graphic - Vertical 8 dots parallel, horizontal 640 dots serial/line is Phenolic: The price is amazingly for low fully imported English quality. Character size: 2.lmm )0.083"). W x 2.4mm 10.09'1- H/7 x 8 dot matnx Cat HP9550' ONLY $3.49 Character set: 228 ASCII characters, Normal and italic alphanumeric )ono, symbols and semi.graphics JAYCAR is proud to announce that vse now stock !range of quality VERO hardware. Printing speed. 80 CPS, 640 dots/line per second Line feed time. Approximately 200msec at 4.23mm )1/16") line feed PC PIN INSERTION TOOL & SPOT FACE CUTTER Printing direction: Normal - Bidirectional, logic seeking Superscript and bet image graphics - Unidirectional, left to right FOR VERO BOARD Dot graphics density: Normal -640 dots/190.5mm (7.5""1 line horizontal, This handy little inserter will save you hours of rime over Its lifetime) You can use Compressed characters - 1,280 dots/190mm (7.5") line horizontal it to push home PC pins Irons about 1.0 to 1.2mm diameter! It's not really cheap Line spacing: Normal - 4.23mm (1116'") at 57.99 but the quality is there. Programmable in increments o1 0.35mm (1/721 and 0.118mm (1/216"1 Cat. TH1835 57.99 Columns/line: Normal size - 80 columns Spot Ice cutter. Will efficiently remove excess copper strip from Vero type boards. Double width - 40 columns Cat TH1836 $4.95 Compressed print - 142 columns Compressed/double width - 71 columns 9V The above can be mixed In a line (216 TYPE) BATTERY COMPARTMENT Paper feed: Adjustable sprocket feed and frkhon feed This Cleve r little device is basically a tax with a hinged lid. You cut a rectangular Paper type: Fanfold. Single sheet Paper width - 101.6mm (4") to 254mm (10") the hole in side of your equipment and the box snaps into the hole. You can fit a Number of copies: Original plus 3 copies by normal thickness paper 9V 216 cell in the compartment and replace it when necessary without dismantling .. MECHANICAL SPECIFICATIONS your equipment! Each unit Is supplied with a quality 9V battery snap as well! Il Ridwn: Cartridge ribbon (exclusive use), Hack Cat PH9240 ONLY $3.95 MTBF: 5 million lines (excluding print head life) Print head life: Approximately 30 million characters (replaceable) INTERFACE SPECIFICATIONS GOOD-BYE 3002 11 Interlace: Standard Centronics parallel Data rate. 4.000 Many people unfortunately missed out when we last advertised transfer CPS max our 3002 amplifier kit (2 a 300Wr.m.s. I. Such was the disappoint Synchronization: By external supplied STROBE pulses ent and because we had many components left over, we decided Handshaking. By ACKNLG or BUSY signals to do another batch. This batch is now complete and is definitely Logic level. Input data and all interface control signals are TTL level the last of the line. If you want to purchase one of these at 5399 SUPPLIED WITH 48 PAGE MANUAL !normally 54891 is last please hurry cos this your chanter! AND 13 DIFFERENT PRINTING MODES e.g normal. condensed, enlarged, emphasised, underlined, italic, etc. And remember - GRAPHICS as well LIMITED STOCK CALL IN NOW FOR A DEMO! >619_139'9' Cat YM2400 SEE THE OTHER JAYCAR ADS IN THIS MAGAZINE FOR ADDRESS DETAILS proDcc 265 The `power down' mains appliance timer Have you ever turned on your electric radiator to warm a room in the morning and forgotten to turn it off on your way out? What about the patio light - ever turned that on and forgotten to turn it off until the next day? This project will not only solve those problems, but has many applications besides. Geoff Nicholls THIS IS a press -button mains appliance sure times are often handled with a simple ting the divider in preparation for counting. timer. You plug the project into a wall period timer. When making multiple expo- Output B of the flip-flop is low and the relay socket, plug your appliance into the project, sures for comparisons, etc, binary -related ex- is not operated. then press the button to turn the appliance posure times are frequently used, e.g: print When the start button is pressed, the RS on. Some predetermined time later, the pro- exposures of eight minutes, then four min- flip-flop is 'set'. Output B goes high, operat- ject will automatically 'power down' (or turn utes, then two minutes, etc. ing the relay and turning on the appliance off) your appliance. This versatile little timer will handle all connected via the relay. Output A goes low, No doubt you're familiar with those time the above applications and can be configured enabling the divider to count down. switches installed in the stair wells of apart- to suit a huge variety of other applications, At the end of its count, the divider's output ment buildings that control the stairway probably only limited by your imagination. goes low, resetting the flip-flop. Output A lights. You press the big button and the This project can be set up for timing goes high again, stopping the divider, and lights come on just long enough for you to not periods ranging from one minute up to at output B goes low. The relay then drops out, quite make it up the stairs! These devices least 50 hours. Although I haven't tried it, it turning off the appliance connected via its employ a mechanical timer, their major is certainly possible to extend the period to contacts. problem being that, with use, the period de- around 400 hours (16-17 days). Binary 'seg- The oscillator's frequency will determine creases. In addition, you can't preset them to ments' of the basic period can be selected by the basic period. Because the division ratio is a convenient time over a wide range. the simple addition of a suitable switch. The so high, minor drifts or variations in the os- Many 'deluxe' electric heaters these days project is low in cost and can be built into an cillator frequency will not materially affect incorporate a timer of some sort so that the appliance if you so wish. the timing period, hence a simple oscillator heater can be turned on for a preset period, can be used. then turn itself off. 'Super deluxe' models go As the required timing period is deter- so far as having a timer with digital display Design mined by Rl, RV1 and C3, the values you and pii-ogramming facilities to turn it on and need for these components should be de- off whenever you like each day for a fort- The unit is quite straightforward. Figure 1 termined from Table 1 before commencing night! That's probably going a bit far for shows a block diagram. It consists of an oscil- construction. It would be reasonable to ex- many applications, though. lator, a divider, a flip-flop, a relay driver and pect a kit supplier not to include these in a Getting 'closer to home', so to speak, take relay. The relay contacts are used to connect kit, or to perhaps only include, say, a lu the case of an EPROM eraser. This basically and disconnect the mains power from an at- RBLL or tantalum for C3 and perhaps a 1M comprises an ultraviolet lamp and a period tached appliance. trimpot, as these would cover a wide range of timer. You bung your EPROMs under the The oscillator output is divided down 8192 timing periods, leaving the choice of R1 to lamp and turn on the timer. The timer then times. The divider's output drives the 'reset' you. turns the lamp off the required period later input of the 'reset -set' (RS) flip-flop. The flip- Note that C3 should either be a tantalum (typically, 20 minutes). flop has two outputs -A and B. In the type or single -ended 'low leakage' electro- In photographic work, film and print expo- initial, or reset, state, output A ís high, reset - lytic for repeatable results. Circuit. See Table 1 for the values of R1, RV1 and C3. R2 IC2 100 40938 IC2a D5 IN914 DlD4 3 194001 RL1 o D1 SWITCHED D2 IC3 PB1 R4 IC2tl 1 2k2 OUTPUT OUT 40208 NC 240 Vac IN ICI 13 0 7812 CLOCK _cr/ IC2c R3 Ot GND 11 470k BC548 CO 3 D3 + 014 4O NO 4 RV1 LED1 C2 RESET 10 9 Cl 100n 11 C4 470u R1 2851 25 V C3T 'SEE TABLE I 90 - July 1983 ETI °powsa9 down' IáangT HOW IT WORKS - ETI-265 The overall design of the protect is discussed in the text, so this shall largely be a blow-by- blow description of how it works. Let us start at the 'rear end' first. Two gates from the 4093, IC2a and b, form the reset -set (RS) flip-flop. This is in the SET state when pin 3 of IC2 is high and pin 4 is low. It is in the RESET state when pin 4 is high and pin 3 low. When the flip-flop is SET, 01 is turned on as the high on pin 3 of IC2 biases on its base via R4 and LED1, which lights, indicating the unit is 'active'. A momentary low on pin 1 of IC2 will SET the flip-flop, while a momentary low on pin 6 will RESET it. On power -up, C4 will look like a short circuit and keep pin 6 of IC2 low long enough to RE- SET the flip-flop. Thus, pin 4 of IC2 will be high and reset IC3, a 40201114 -stage binary counter with a division ratio of 8192:1. Pin 3 of IC3 (the stage 14 output) will be low after the IC is reset and IC2 will invert this, pin 10 driving pin 6 high, allowing the flip-flop to be set when PB1 is pushed momentarily. As soon as PB1 is pushed, the counter be- gins to count cycles of the Schmitt gate oscil- lator comprising IC2d, R1, RV1 and C3. The frequency of the oscillator is determined by RV1, R1 and C3 and the threshold voltages of the inputs of IC2d. (See 'Why some CMOS circuits don't work as you expect', Lab Notes, in this issue.) o After 8192 cycles of the oscillator, pin 3 of IC3 goes high, thus resetting the flip-flop vial IC2c. Pin 3 of IC2 will thus go low and the relay !a, will drop out. The oscillator work. as follows: At power - up, pin 12 of IC2d will be low as C3 appears as a short circuit. Pin 13 will be high and thus pin 11 will be driven high. C3 will charge via R1 and RV1. When the voltage on C3 reaches the gate's upper threshold, pin 11 will go low and C3 begin to discharge via RV1 and R1. When the voltage on C3 falls to the gate's lower threshold, pin 11 will again go high and the cycle will be repeated. The oscillator frequency is related to the tim- ing interval (or period) as follows: fo=8192 T where fo is the oscillator frequency in Hertz, and T is the period in seconds. Expressing this in terms of the period: T=8192 to Table 1 allows you to set up the project for a particular timing interval. The range of adjust- A ment provided should compensate for most of On the inside. Showing construction of the project and how the variation in threshold voltages of the dif- ferent I mounted it inside the Unibox case. Note that one of the manufacturers' 4093s. The time interval internal pillars is cut down to provide clearance for the shown in the table refers to the prototype pro- O N/C irantformer. Inset. The completed project. t ject. If you add the rotary switch to give four RELAY COMMON ranges, the longest interval will be as per the O N/O table, the next will be half that, then quarter that, etc. The power supply is quite straightforward. RELAY Figure 1. Block diagram Transformer T1 drops the mains voltage tó DRIVER of the 'power down' unit. 12.6 V RMS. This is rectified by a bridge diode comprising D1 to D4. Capacitor Cl is the START rectifier reservoir. About 18 volts is developed set across Cl and 12 o as this is regulated to V by a 1 FLIP FLOP 7812 three-terminal regulator, IC1. Capacitor OSCILLATOR 8192.CYCLE reset DIVIDER C2 ensures regulator stability. Diode D5, across the relay, shorts the reset reverse -em! generated by the relay coil when 01 switches off, preventing the high voltage generated from destroying 01. ETI July 1983 - 91 SATIONAL SCOO S BRILLIANT NEW FAX 80 ky DOT MATRIX PRINTER ouAun LESS THAN $700 Just a few short months ago we were selling printers of comparable quality and spe- cification for around $1000. With the release of the excit- ing new FAX -80 and our bulk Character set: we are of- 228 ASCII characters: Normal and italic purchase powers alpha -numeric font, Symbols and semi- fering these for sale at ggraphics. just IMnting speed: $699.50. 80 CPS, 640 dots/line per second. Hurry - present stocks are Printing direction: Normal - Bidirectional, logic seeking. limited. Superscript and bit image graphics - GENERAL INFORMATION Unidirectional, left to right. Doe space This printer is designed to Normal - 4. 3mm 11 /61. operate through software Programmable In increments of from any 0.35mm 11/72"1 and 0.118mm 11/216"1. control, supplied Columns/line: general purpose microcom- Normal size - 80 columns. puter, personal computer, r Double width - 40 columns, Computer etc. that has Compressed print - 142 Columns. office Compressed double width - 71 provision of printing data Columns. out -put that should conform The above can be mixed In a line. It Paper feed: with this specification. Adjustable sprocket feed and friction prints upper -and lower-case feed. alpha -numeric characters in Paper type: italic letter Fanfold. Single sheet. both normal and 101.6mm 141 to 254mm forms, and graphic charac- Interface specifications Functional specifications Paper width - interface: Printing method: 110'9. ters available on the charac- Standard Centronics parallel. Optional Serial Impact dot matrix. ter code set of this printer RS -232C. (SERIAD. Printing format VALUE PACKED AT beside capability of bit Data transfer rate: Alpha -numeric -7 x 8 in 8 x 9 dot 4,000 CPS max. matrix field. CAT. D 1170.... $699.50 image graphic printing it is Synchronization: Semi -graphic (character graphic) -7 x also functionated. Addi- By external supplied STROBE pulses. 8 dot matrix. tionally this printer has con- Handshaking: Bit Image graphic - vertical 8 dots Printer Cable interface Kit By ACKNLG or BUSY signals. parallel, horizontal 640 dots serial/line. siderable formatting cap- Logic level: Character size: to suit Mlcrobee ability owing to its own inter- Input data and all Interface control 2.1mm 10.0831-W x 2.4mm nal microprocessor system. signals are TTL level. (0.09").14/7 x 8 dot matrix. D 1190 $49.95 THE ULTIMATE THE FANTASTIC MICROBEE GUIDE TO IC HAS ARRIVED CP/M W IIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIII IIIIIIIIHIIIIIIIIIIIIIliIinnIIIIIIInl 11111111111 y NEW 3.375 mHz AVAILABLE IN CLOCK SPEED 16 K or 32 K VERSIONS W n 7 1IIIIIIIIIIII111111(111111111111111111111 11111111, IIIII111IIIIIIIIIIIIIl11IIIIIII __ 64 x 16 OR 80 x 24 SCREEN FORMAT OVER 10,000 ONLY IIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIri MICROBEES SOLD .IIIIIIIIIIIIIIIIIIIIIIIIII11I11111111111 B 9080 $41.95 wordprocessor Penned by International Computer expert David E. The all new Microbee IC has got to be the ly delightful Wordbee INSIDE is divided into a Tutorial Sec- plus all the Cortesi, CP/M most value packed ROM based personal package and Editor Assembly tion and a Reference Section. The tutorial Is again computer available today. New enhanced other exciting features that have made the divided Into four sections, one for Novices, Users, basic enables 64 x 16 or 80 x 24 screen for- Mlcrobee famous. 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Now you can save and load software in your Micro ALTRONICS with confidence. 105 STIRLING ST.. PERTH Micron D 1120 FOR INSTANT Data Cassette SERVICE ONLY $49.50 D 1140 C10 Data Cassette (09) 328 1599 Tape $1.10 D 1141 C20 Data Cassette All Mall Orders: Box 8280, St., WA 6000. Tape $1.20 Stirling Perth prroDsca 2E5 Now solder the electrolytic, CI, in place, Test and calibration taking care to orientate it correctly, followed by IC1 (get it the right way round) and RV1. Set RV1 to the middle of its travel, then close Construction The relay can be soldered to the board last of the case so that you can't accidentally come in with the lethal mains voltage I built one prototype and mounted it in a all. contact plastic case, which you see in the photo- Wires are run from the pc board to the present. into socket, graphs here, and another unit which I mains circuitry, the pushbutton and the Plug a bedside lamp the output mounted inside an appliance (ask no ques- LED. Only ordinary light hookup wire plug the project into the mains and switch tions and ...) (10 x 0.12 mm) need be used to connect up on. Nothing should happen. If all's well, and lamp should I used an all -plastic Unibox (P/N144) the LED and the pushbutton. The 2851 press the pushbutton the on it's measuring 135 mm long by 100 mm wide by transformer primary wires are generally col- light. Now time how long it remains (if lot 50 mm deep. (Magraths in Melbourne are a oured red and black. It has three secondary 50 hours or more, you're going to need a of major supplier of these.) It has ample room wires, two the same colour. These are wired patience!). inside. You could use a UB-1 zippy box to the rectifier diodes DI -D4, as shown in the If you have access to a frequency counter, (50 x 90 x 150 mm), but an all -plastic case is overlay/wiring diagram. then setting the timer is much easier. Just recommended for safety's sake. Jaycar stock Wire the transformer primary very care- attach the frequency counter to pin 11 of IC2. a range of smart, all -plastic (ABS) cases in fully. The brown active wire from the mains The oscillator frequency is related to the tim- various colours. The HB6150, 1, 2, 3 series input cable goes to a terminal connector, ing period as follows: (orange, grey, blue, black) would suit. where it joins the red wire from the trans- Frequency = 8192 First thing to do is determine the mount- former. Take a length of brown mains wire T ing positions of the printed circuit board and and connect it between this terminal con- where T is the desired period in seconds and transformer. Lay the unassembled pc board nector and the COMMON relay terminal pad the frequency is in Hertz. and the transformer in the base of whatever on the pc board. Another length of brown For a timing period of ten minutes, the box you're using and mark the positions of mains wire is run from the normally open frequency should be 13.65 Hz. For really the mounting holes. (N/O) relay contact pad on the pc board to the long times, you're better off measuring the Then mark out suitable positions for the active terminal of the mains output socket. period of the oscillator output. mains cable entry, the pushbutton, the LED The blue neutral wire runs from the mains All you need do is to adjust RV1 for the and the mains socket. For the mains cable input cable direct to the neutral terminal on correct frequency. entry, I used a Heyco clamp -type grommet to the mains output socket, along with the suit the mains cable I used (grommet #1210, black wire from the transformer. Binary periods SR -6P-4). There are plenty of similar types The green and yellow striped earth wire available. If you don't use a clamp -type from the mains input cable goes direct to the As mentioned earlier, the simple addition of grommet, then use an ordinary rubber grom- earth terminal on the mains output socket. a switch can give you binary (half, quarter, Details met and a nylon cable clamp. This wire should be longer than the other eighth) segments of the basic period. The mains socket requires holes to be dril- two from the mains input cable for safety are shown in Figure 2. led in the box to allow cables to the active, reasons. Should the mains cable be acciden- Cut the track that runs beneath the body neutral and earth pins to pass through to the tally pulled out from the case, the earth wire of IC3, then wire a single -pole, four -position Position 4 gives you the full socket terminals. I first loosened the grub will be the last to break. switch as shown. screws on the socket terminals, then posi- All finished? Check everything thoroughly. period. Position 3 gives the half period, posi- 2 and position 1 gives one - tioned the socket where I wanted it and That's all there is to it. Next thing to do is tion one -quarter drilled pilot holes in the case through the test and calibrate it. eighth the period. terminals. After drilling all the holes, mount the transformer, output socket, LED and push- 24°V button, but not the pc board - you've got to °. assemble that yet! To mount the trans- .Wdl O former, I used insulating washers from a 0 TO -3 power transistor mounting kit. An al- O O - ternative is to use nylon bolts. The latter were used to mount the pc board. o Note that, if you wish, the section of the board on which the relay mounts can be Z9i»C severed from the rest of the board, allowing . eti the relay to be mounted away from the main 265 portion of the electronics. O O Assembly of the board is pretty straight- forward. Start with the smaller components. Solder all the resistors in place, then the five PARTS LIST - ETI-265 LED1 TIL220R red LED diodes, C2, C3 and C4. Watch the orientation 01 BC548 Resistors all +/a W, 5% unless noted diodes. Solder a link of tinned Miscellaneous of C3 and the R1 47k PB1 momentary copper wire in the position shown, between R2 100k action large C4 and R4. Now you can solder IC2 and IC3 R3 470k pushbutton, (e.g: in place. R4 2k2 D.S.E. no. S-1199 or These are CMOS ICs. Use an iron with an Capacitors similar) RL1 pc mount relay, 12 V coil ICs with Cl 470u/25 V single -ended earthed tip and only handle the A electro. SPDT/5 contacts your thumb and forefinger gripping the ends (e.g: D.S.E. S-7125, or C2,C4 100n greencap of the package. Avoid touching the pins. similar) C3 1u/16 V tantalum When you have each in place, solder pins 7 T1 2851 transformer, 12.6 V Semiconductors 14 IC2 first and pins 8 and 16 of IC3 CT @ 150 mA and of -D4 1N4001, 1N4002 or pins. D1 ETI-265 pc board; case to suit (e.g: Unibox P/N first, before going on to solder the other similar 144, 100 x 135 x 50 mm, or similar); LED mount; If you wish, IC sockets may be used without D5 1N914,1N4148 240 V wall socket; mains cable plug, cable and affecting operation of the project. IC1 7812 clamp; wire, etc. Next solder Ql in place. Its orientation can IC2 4093B be ascertained from the pinout diagram and IC3 40200 Price estimate S32 -S37 the component overlay. 94 - July 1983 ETI WST lOO Wr/9 Offnal electrolytic tantalum band + LED1 -4 flat e c BC548, k BC108 ó -{11111w Diodes INPUT Ql corro« OUTPUT G LINK Ob@ OUT SPOT OA NOTCH Ol.2 111: ..- T Al THIS END d TTp - C3 TT7. W.» 1 RL1 0 ICs e4 PB1 3 ' MAINS CABLE CABLE CLAMP BROWN BLUE rote 240 Vac T1 2851 240 Vac e MAINS RED SOCKET TERMINAL e BLOCK E BLACK BOTTOM VIEW GREEN/YELLOW (LONGEST) Binary period switching. How to add a switch to get selections of full period, Timing Interval C3 R1 RV1 half period, quarter period and eighth period. ROTARY SWITCH 1 minute 100n 47k 100k (REAR VIEW) 5 minutes 100n 270k 500k 2 10 minutes 100n 470k 1M 20 minutes 1u 100k 220k 30 minutes 1u 150k 220k 45 minutes 1 u 270k 500k 1 hour 1u 270k 500k P81 11/2 hours 1u 390k 1M 2 hours 1u 680k 1 M 4 hours 1u 1M2 2M2 10 hours 100u 27k 50k 20 hours 100u 56k 100k 50 hours 100u 150k 200k 100 hours 100u 270k 500k 200 hours 100u 560k 1M 400 hours 100u 1M2 2M TABLE 1 ETI July 1983 - 95 1°or-1 ROD IRVING ELECTRONICS 425 High St. Northcote, Ph.: (03) 489 8131 2 BRANCHES: 48-50 A'Beckett St. Melb. Ph.: (03) 347 9251 Mail orders: P.O. Box 235 Northcote, Vic. 3070 min p&p $3.00 PANEL METERS MU45 Panel Meters MU52E Panel Meters MU65 Panel Meters r a0 60 100 700 .6 10 1 .4 t 1 p o 0/0,/ D C AC D C MICROAMPERES VOLTS 'S(11LLI AM PERES w.,... w.. Mu .5 centres. Mounting hole distance between centres. Mounting hole distance between centres. Mounting hole distance between 38mm x 38mm. 64mm x 48mm 80mm a 64mm. Hole required 45mm overall dimension. Hole required 51 mm overall dimension. Hole required 65mm overall dimension. Outside dimension. Outside dimension. Outside dimension, 58mm x 52mm. 80mm x 66mm. 100mm a 82mm. HR15 PANEL METERS 1-9 10+ 010500 MU45 0-1mA 9.75 7.95 2 3 6 7 8 010502 MU45 50-0-50uA 9.75 7.95 4 010504 MU45 0-100uA 9.75 7.95 Lnaaaao 010505 MU45 0-50uA 9.75 7.95 010518 MU45 0-1A 9.75 7.95 it.i---P orM~I 1-9 10+ 010510 MU45 0-5A 9.75 7.95 010400 4.50 3,95 010515 MU45 0-10A 9.75 7.95 250 ua Sensitivity Panel cut-out 36mm x 16mm. 010520 MU45 0-20V 9.75 7.95 Mounting hole centres at 49mm. 010525 MU45 0-30V 9.75 7.95 010535 MU45 VU 10.95 9.95 010530 MU52E 0-1mA 10.95 8.95 H46 010533 MU52E 0-5A 10.95 8.95 010538 MU65 0-50uA 13.95 11.95 010540 MU65 0-1mA 13.95 11.95 010550 MU65 0-100uA 13.95 11.95 0 010560 MU65 0-20V 13.95 11.95 1 1 1 l l rp: = 1-9 10+ 010405 4.95 4.50 Errors and omissions excepted. 250 ua Sensitivity centre '0' very useful for balanced 010410 1-9 10+ VU Meter. 9.95 8.95 circuit and applications needing a centre '0' or null Stereo Please ignore scales on indication. Panel Meter photos RITRON DIGITAL MULTIMETERS 28 Ranges Push Button Operation Auto Polarity Low Battery Indicator Full overload protection Finger guards on Probes and Shrouded plugs for safety Accuracy: 1 year 18°C to 28°C (+% of Reading + No. of Digits). ale. SPECIFICATIONS: 016010 200 hour battery 5591.95 554.95 \,V.T ANY 011,1 L INIT 1k AC CM) OC AC l'IT e.YL.0i1111 J 5.1 M / 1.999 \ :1I 1.11.5 1 ul.l 0 J1.1 1\' Iv : 15.5 vo 1.1 5+ 017040040 2000 hour oattery life 589.95 584.95 Y\N15 \,1T AMP 111,1.c*ITT_ >_ U áa4 0 ye .. 100. q\ea r .. . , / v. 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If your work involves average sensing does not give an 100kHz measuring temperature then connect a accurate result - especially with non - Frequency measurement to 200kHz K -type thermocouple and you can get sinusoidal waveforms. If you work with dBm and relative dB direct temperature readings (we have a motors or data transmission type 10NV sensitivity range available specially to suit the circuitry. true rms Is critical to your Direct resistance measurement to 8024B). measurements. For quick circuit 300Meg checking the 8026A also incorporates Relative reference on any range or 11 functions including temperature with the Fluke high speed continuity beeper. function K -type thermocouples Microcomputer -based self diagnostics Peak hold on voltage and current ranges 8 functions 8062A Logic detection and continuity True rms AC measurements to 10kHz As 8060A above but without frequency and dB Audible and visible indicators Conductance and diode testing ranges. Provides true rms to 30kHz and relative 0.1% basic accuracy. 31/2 digit High speed continuity beeper reference functions. 4=lc.35 co 11312:111121 11 ( A 1 T VI A .. .'. Lt.,1_cl _ , 4 t r 1 =El CHECK THE COMPLETE FLUKE FLUKE 8020B SERIES a c` < i.+ss SOLD sct Jrc `cc cc D & SERVICED IN AUSTRALIA BY se a %° Ñc . \: ..`O.: F : : e 41"9°D i- ?' <1.P Z- ct'CCCt- ELMEASCO :.=:: 90228 0 259 80218 oss7: Instruments Ply/. Ltd. 811611A Iun '!Ikl I I14', kill (NT20B O 19 u. MIBi2 \ 8024B 01: klIi All prices are plus Sales Tax if applicable and subject to change without notice. SEND FOR YOUR FREE MULTIMETER P.O. Box 30. Concord P.O. Box 107, Mt. Waverley Adelaide: (08) 271 1839 GUIDE N.S.W. 2137 Victoria 3149 Brisbane: (07) 369 8688 pmaziumuzummommammil Please send me details of Fluke DMMs 13-15 McDonald Street. 21-23 Anthony Drive, Perth: (09) 398 3362 Mortlake, N.S.W. Mt. 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Board Width Box Dimensions Vertical Horizontal Price this month H 0101 150 x 9Óx 50 90 87 1.90 H 0102 195x 113x60 106 103 2.90 H 0103 130x 68x41 62 60 1.80 H 0105 83x 54x28 50 47 1.20 FOR DESPATCH Pik CHARGES AND ADDRESS DETAILS PLEASE REFER TO OUR AD. ON PAGE 93 A. * 1 ETI's practical guide to one of the most versatile' electronic building blocks in use today. 11< o ,11 \26 i age \1O\\G . . G GJ\`5 aG : 2.09 5a et5 o(\ \oQ ,'.0Qe . 0- Qa 11/ oJ G a ' ,er tire g0 i oQs9 \\e. \-05 ' No\eges" Ja.\ao\g Ill \1522>9 0 ETI July 1983 - 99 The op -amp cookbook using the 741 Here's how to use the 741 op -amp - one of the most versatile building blocks of all time. OPERATIONAL AMPLIFIERS (OP -AMPS) CAN be effectively reduces the output offset voltage of the simply described as high -gain direct -coupled voltage differential amplifier to zero volts under quiescent amplifier 'blocks' that have a single output terminal but conditions, and the output of the compensation stage is have both inverting and non -inverting input terminals. fed to a simple complementary emitter follower output Op -amps can readily be used as inverting, rion-invert- stage, which gives a low output impedance. ing, and differential amplifiers in both a.c. and d.c. INVERTING applications, and can easily be made to act as INPUT oscillators, tone filters, and level switches, etc. Op -amps are readily available in integrated circuit OUT form, and as such act as one of the most versatile NON -INVERTING building blocks available in electronics today. One of INPUT the most popular op -amps presently available is the Fig.lb Basic op -amp symbol . device that is universally known as the "741" op -amp In this article we shall describe the basic features of this LINES OF SUPPLY Op -amps are normally powered from split power device, and show a wide variety of practical circuits in (zero volt) which it can be used. supplies, providing +ve, -ve, and common supply rails, so that the output of the op -amp can swing either side of the zero volts value, and can be set at a BASIC OP CHARACTERISTICS AND -AMP CIR- true zero volts (when zero differential voltage is applied CUITS to the circuits input terminals.) In its simplest form, an op -amp consists of a The input terminals can be used independently (with differential amplifier followed by offset compensation the unused terminal grounded) or simultaneously, and output stages, as shown in Fig. 1 a. The differential enabling the device to function as an inverting, amplifier has inverting and non -inverting input non -inverting, or differential amplifier. Since the device terminals, a high -impedance (constant current) tail to is direct -coupled throughout, it can be used to amplify both a.c. and d.c. input signals. Typically, they give basic low -frequency voltage gains of about 100 000 between input and output, and have input impedances of 1M or greater at each input terminal. OFFSET Fig. 1 b the symbol that is commonly used to COMPENSATION shows STAGE represent an op -amp, and lc shows the basic supply INVER TING INPI!T connections that are used with the device. Note that both input and output signals of the op -amp are NON INVERTING INPUT referenced to the ground or zero volt line. SIGNAL BOX OV The output signal voltage of the op -amp is COMSION o o LINE proportional to the DIFFERENTIAL signal between its Fig. la Simplified op -amp equivalent circuit. two input terminals, and is given by eoI = Ao(e 1-e2) give a high input impedance and a high degree of where AG=the open -loop voltage gain of the op -amp common mode signal rejection. It also has a (typically 100 000). high -impedance (constant current) load to give a high el=signal voltage at the non -inverting input degree of signal voltage stage gain. terminal. The output of the differential amplifier is fed to a e2=signal voltage at the inverting input terminal. direct -coupled offset compensation stage, which Thus, if identical signals are simultaneously applied 100 - July 1983 ETI SUPPLY +Ve. OP AMP +Ve SATURATION + I OUT OV DIFFERENTIAL (e, e2I INPUT .4 .3 .2 i.1 .1 .2 .3 .4 - P mV mV B2 -Ve SATURATION ' -Ve T SUPPLY Fig. is Basic supply connections of an op -amp. Fig. 2b Transfer characteristics of the differential to both input terminals, the circuit will (ideally) give zero voltage comparator circuit. signal output If a signal is applied to the inverting terminal only, the circuit gives an amplified and inverted output If a signal is applied to the non -inverting terminal only, the circuit gives an GOING TO GROUND amplified but non -inverted output. The op -amp can be made to function as a low-level By using external negative feedback components, inverting d.c. amplifier by simply grounding the the stage gain of the op -amp circuit can be very non -inverting terminal and feeding the input signal to precisely controlled. SUPPLY +Ve +Ve SUPPLY REFERENCE VOLTAGE OUTPUT (e2) SAMPLE INPUT VOLTAGE SUPPLY OUTPUT -Ve -Ve (el) SUPPLY OV Fig. 2a Simple differential voltage comparator circuit. Fig. 3a Simple open -loop inverting d.c. amplifier. TRANSFER REQUEST Fig. 2a shows a very simple application of the the inverting terminal, as shown in Fig. 3a. The op -amp op -amp. This particular circuit is known as a differential is used 'open -loop' (without feedback) in this voltage comparator, and has a fixed reference voltage configuration, and thus gives a voltage gain of about applied to the inverting input terminal, and a variable 100 000 and has an input impedance of about 1M. test or sample voltage applied to the non -inverting The disadvantage of this circuit is that its parameters terminal. When the sample voltage is more than a few are dictated by the actual op -amp, and are subject to hundred microvolts above the reference voltage the considerable variation between individual devices. op -amp output is driven to saturation in a positive direction, and when the sample is more than a few CLOSING LOOPS hundred microvolts below the reference voltage the A far more useful way of employing the op -amp is to output is driven to saturation in the negative direction. use it in the closed -loop mode, i.e., with negative Fig. 2b shows the voltage transfer characteristics of feedback. Fig. 3b shows the method of applying the above circuit. Note that it is the magnitude of the negative feedback to make a fixed -gain inverting d.c. differential input voltage that dictates the magnitude of amplifier. Here, the parameters of the circuit are the output voltage, and that the absolute values of input controlled by feedback resistors R, and R2. The gain, A voltage are of little importance. Thus, if a 1V reference of the circuit is dictated by the ratios of R, and R,, and is used and a differential voltage of only 200uV is equals R2/R,. needed to switch the output from a negative to a The gain is virtually independent of the op -amp positive saturation level, this change can be caused by a characteristics, provided that the open -loop gain (A0) is shift of only 0.02% on a 1V signal applied to the large relative to the closed -loop gain (A). The input sample input. The circuit thus functions as a precision impedance of the circuit is equal to R,, and again is voltage comparator or balance detector. virtually independent of the op -amp characteristics. ETI July 1983 - 101 FOLLOW THAT VOLTAGE OP-AffiP The op -amp can be made to function as a precision voltage follower by connecting it as a unity -gain non -inverting d.c. amplifier, as shown in Fig. 4b. In this case the input and output voltages of the circuit are COOKBOOK identical, but the input impedance is very high and is It should be noted at this point that although R1 and roughly equal to A0 X Z;,,. R2 control the gain of the complete circuit, they have The basic op -amp circuits of Figs. 2a to 4b are no effect on the parameters of the actual op -amp, and shown as d.c. amplifiers, but can readily be adapted for the full open -loop gain of the op -amp is still available a.c. use. Op -amps also have many applications other between its inverting input terminal and the output. than as simple amplifiers. They can easily be made to Similarly, the inverting terminal continues to have a function as precision phase splitters, as adders or very high input impedance, and negligible signal subtractors, as active filters or selective amplifiers, as current flows into the inverting terminal. Consquently, precision half -wave or full -wave rectifiers, and as virtually all of the R, signal current also flows in R2, and oscillators or multivibrators, etc. R1 INPUT OUTPUT OV R2 o o Fig. 4b Basic unity -gain d.c. voltage follower OP -AMP PARAMETERS Fig. 4a Basic non -inverting d.c. amplifier An ideal op -amp would have an infinite input impedance, signal currents i, and i2 can be regarded as being zero output impedance, infinite gain and equal, as indicated in the diagram. infinite bandwidth, and would give perfect tracking Since the signal voltage appearing at the output between input and output. Practical op -amps fall far terminal end of R2 is A times greater than that short of this ideal, and have finite gain, bandwidth, etc., appearing at the inverting terminal end, the current and give tracking errors between the input and output flowing in R2 is A times greater than that caused by the signals. Consequently, various performance parameters inverting terminal signal only. Consequently, R2 has an are detailed on op -amp data sheets, and indicate the appárent value of R2/A when looked at from its measure of "goodness" of the particular device. The inverting terminal end, and the R1-R2 junction thus most important of these parameters are detailed below. appears as a low -impedance VIRTUAL GROUND point. OPEN -LOOP VOLTAGE GAIN, A0. This is the low -frequency voltage gain occuring directly between the input and output terminals of the op -amp, and may SUPPLY be expressed in direct terms or in terms of R1 dB. +Ve Typically, d.c. gain figures of modern op -amps are 100 000, or 100dB. OP -AMP INPUT + INPUT IMPEDANCE, Z,0. This is the impedance VIRTUAL GROUND OUTPUT looking directly into the input terminals of the op -amp POINT SUPPLY when it is used open -loop, and is usually expressed in -Ve terms of resistance 0v only. Values of 1M are typical of modern op -amps with bi-polar input stages, while F.E.T. input types have impedances of a million meg or Fig. 3b Basic closed -loop inverting d.c. amplifier. greater. INVERT OR NOT TO INVERT... It can be seen from the above description that the OUTPUT IMPEDANCE, Z0. This is the output Fig. 3b circuit is very versatile. Its gain and input impedance of the basic op -amp when it is used impedance can be very precisely controlled by suitable open -loop, and is usually expressed in terms of choice of R, and R2, and are unaffected by variations in resistance only. Values of a few hundred ohms are the op -amp characteristics. A similar thing is true of the typical of modern op -amps. non -inverting d.c. amplifier circuit shown in Fig. 4a. In this case the voltage gain is equal to (R,+R2)/R2 and INPUT BIAS CURRENT, I,. Many op -amps use bipolar the input impedance is approximately equal to transistor input stages, and draw a small bias current (A0/A)Zin where Zin is the open -loop input impedance from the input terminals. The magnitude of this current of the A great is op -amp. advantage of this circuit that it is denoted by lb, and is typically only a fraction of a has a very high input impedance. microamp. 102 - July 1983 ETI The f figure can thus be used to represent a SUPPLY VOLTAGE RANGE, V, Op -amps are usually gain -bandwidth product. operated from two sets of supply rails, and these supplies must be within maximum and minimum +120 DASHED LINES = CLOSED -LOOP limits. If the supply voltages are too high the op -amp RESPONSE may be damaged, and if the supply voltages are too low +100 the op -amp will not function correctly. Typical supply limits are ±3V to ± 15V. +80 +60 OPEN -LOOP INPUT VOLTAGE RANGE, VI(m,Xr The input voltage to RESPONSE the op -amp must never be allowed to exceed the supply +40 line voltages, or the op -amp may be damaged. V,Ima,) is usually specified as being one or two volts less than v5. +20 OUTPUT VOLTAGE RANGE, Volmat4 If the op - amp is over driven its output will saturate and be -20 1 10 100 1k 10k 100k 1M 10M limited by the available supply voltages, so Volmasi is usually specified as being one or two volts less than Vs. FREQUENCY-Hz Fig. 5 Typical frequency response curve of the 741 op -amp. DIFFERENTIAL INPUT OFFSET VOLTAGE, Vb In the ideal op -amp perfect tracking would PARAMETER 741 VALUE exist between the input and output terminals of the A. OPEN.LOOP VOLTAGE GAIN 100dB device, and thé output would register zero when both ZIN INPUT IMPEDANCE 1M inputs were Actual are not perfect Z,, OUTPUT IMPEDANCE 1508 grounded. op -amps lb INPUT BIAS CURRENT 200nA devices, however, and in practice slight imbalances Vs IMAXI MAXIMUM SUPPLY VOLTAGE '18V exist within their input circuitry and effectively cause a V, IMAXI MAXIMUM INPUT VOLTAGE .'13V small offset or bias potential to be applied to the input Vo IMAXI MAXIMUM OUTPUT VOLTAGE .14V terminals of the op -amp. Typically, this DIFFERENTIAL Vlo DIFFERENTIAL INPUT OFFSET VOLTAGE 2n,V COMMON MODE REJECTION RATIO 90dB INPUT OFFSET VOLTAGE has a value of only a few FT TRANSITION FREOUENCY 1MHZ millivolts, but when this voltage is amplified by the gain S SLEW RATE 1V/uS of the circuit in which the cp-amp is used it may be Table 1 Typical characteristics of the 741 op -amp. sufficient to drive the op -amp output to saturation. Because of this, most op -amps have some facility for normal externally nulling out the offset voltage. SLEW RATE. As well as being subject to bandwidth limitations, op -amps are also subject to a COMMON MODE REJECTION RATION, c.m.r.r. The phenomenon known as slew rate limiting, which has ideal op -amp produces an output that is proportional to the effect of limiting the maximum rate of change of the difference between the two signals applied to its voltage at the output of the device. Slew rate is input terminals, and produces zero output when normally specified in terms of volts per microsecond, identical signals are applied to both inputs simultan- and values in the range 1V/us to 10V/us are common eously, i.e., in common mode. In practical op -amps, with most popular types of op -amp. One effect of slew common mode signals do not entirely cancel out, and rate limiting is to make a greater bandwidth available to produce a small signal at the op -amps output terminal. small output signals than is available to large output The ability of the op -amp to reject common mode signals. signals is usually expressed in terms of common mode rejection ratio, which is the ratio of the op -amps gain THE 741 OP -AMP. with differential signals to the op -amps gain with Early types of i.c. op -amp, such as the well known common mode signals. C.m.r.r. values of 90dB are 709 type, suffered from a number of design typical of modern op -amps. weaknesses. In particular, they were prone to a phenomenon known as INPUT LATCH -UP, in which TRANSITION FREQUENCY, fT. An op -amp typically the input circuitry tended to switch into a locked state if gives a low -frequency voltage gain of about 100dB, special precautions were not taken when con- and in the interest of stability its open -loop frequency necting the input signals to the input terminals, and response is tailored so that the gain falls off as the tended to sell -destruct if a short circuit were frequency rises, and falls to unity at a transition inadvertently placed across the op -amp output frequency denoted fr. Usually, the response falls off at a terminals. In addition, the op -amps were prone to rate of 6dB per octave or 20dB per decade. Fig. 5 bursting into unwanted oscillations when used in the shows the typical response curve of the type 741 linear amplifier mode, and required the use of external op -amp, which has an f, of 1 MHz and a low frequency frequency compensation components for stability gain of 100dB. control. Note that, when the op -amp is used in a closed -loop These weaknesses have been eliminated in the type amplifier circuit, the bandwidth of the circuit depends 741 op -amp. This device is immune to input latch -up on the closed -loop gain If the amplifier is used to give a problems, has built-in output short circuit protection, gain of 60dB its bandwidth is only 1 kHz, and if it is and does not require the use of external frequency used to give a gain of 20dB its bandwidth is 100kHz. compensation components. The typical performance ETI July 1983 - 103 OP-AffiP COOKBOOK OFFSET TAB NC V OW NULL OFFSET NULL INPUT OUTPUT Fig. 8b Variable gain (x x 100) INPUT OF FSE T l to inverting LI 111 U0 NULL d.c. amplifier. OFFSET V- NULL INPUT - INPUT (AND CASE) BASIC LINEAR AMPLIFIER 8 pin Minidip or DIP 741 TOS 741 PROJECTS. (Figs. 8 to (Top View) (TOP VIEW) 11). Fig. 6 Outlines and pin connections of the two Figs. 8 to 11 show a variety of ways of using the most popular 741 packages. 741 in basic linear amplifier applications. The 741 can be made to function as an inverting amplifier by grounding the non -inverting input terminal characteristics of the device are listed in Table 1. and feeding the input signal to the inverting terminal. The type 741 op -amp is marketed by most i.c. The voltage gain of the circuit can be precisely manufacturers, and is very readily available. Fig. 6 controlled by selecting suitable values of external shows the two most commonly used forms of feedback resistance. Fig. 8a shows the practical packaging of the device Throughout this chapter, all connections of an inverting d.c. amplifier with a pre-set practical circuits are based on the standard 8 -pin gain of x100- The voltage gain is determined by the dual -in -line (D.I.L. or DIP) version the of 741 op -amp. ratios of R, and R2, as shown in the diagram. The gain can be readily altered by using alternative R, and/or R2 values. If required, the gain can be made variable by using a series combination of a fixed and a OUT variable resistor in place of R2, as shown in the circuit of Fig. 8b, in which the gain can be varied over the range xl to x100 via R2. VARIATIONS A variation of the basic inverting d.c. amplifier is 10k shown in Fig. 9a. Here, the feedback connection to R2 (OFFSET NULL) is taken from the output of the R3-R4 output potential TO SUPPLY -Ve divider, rather than directly from the output of the is Fig. 7 Method of applying offset nulling to the op -amp, and the voltage gain determined by the 741 op -amp. ratios of this divider as well as by the values of R, and The 741 op -amp can be provided with external offset nulling by wiring a 10k pot between its two null terminals and taking the pot slider to the negative supply rail, as shown in Fig. 7. Having cleared up these basic points, let's now go on and look at a range of practical applications of the 741 op -amp. R1 10k 4 -9v OUTPUT Fig. 9a High impedance x 100 inverting d.c. amplifier. R2. The important feature of this circuit is that it enables ov R,, which determines the input impedance of the circuit, to be given a high value if required, while at the same time enabling high voltage gain to be achieved. Fig. 8a x 100 inverting d.c. amplifier. The basic inverting d.c. amplifier can be adapted for 104 - July 1983 ETI a.c. use by simply wiring blocking capacitors in series with its input and output terminals, as shown in the x100 inverting a.c. amplifier circuit of Fig. 9b. +9v RV1 100k OUTPUT INPUT R1 1k01 OV Fig. 10b Non -inverting variable gain (x1 to x 100) d.c. amplifier. Fig. 9b x 100 inverting a.c. amplifier. BLOCKING OUT The basic non -inverting d.c. circuit of Fig. 10 can be modified to operate as a.c. amplifiers in a variety of NON -INVERTING ... ways. The most obvious approach here is to simply wire The amp can be made to function as a non -inverting blocking capacitors in series with the inputs and amplifier by feeding the input signal to its non -inverting outputs, but in such cases the input terminal must be terminal and applying negative feedback to the d.c. grounded via a suitable resistor, as shown by R3 in inverting terminal via a resistive potential divider that is the non -inverting x100 a.c. amplifier of Fig. 1 1a. If this connected across the op -amp output. Fig. 10a shows resistor is not used the op -amp will have no d.c. the connections for making a fixed gain (x100) d.c. stability, and its output will rapidly drift into saturation. amplifier. Clearly, the input resistance of the Fig. 1 1 a circuit is The voltage gain of the Fig. 10a circuit is determined equal to R3, and R3 must have a relatively low value in by the ratios of R, and R2 If R2 is given a value of zero the interest of d.c. stability This circuit thus loses the the gain falls to unity, and if R, is given a value of zero non -inverting amplifier's basic advantage of high input the gain rises towards infinity (but in practice is limited resistance. to the open -loop gain of the op -amp). If required, the gain can be made variable by replacing R2 with a +9V C2 Op1 C1 Op1 1-0 R2 100k OUTPUT INPUT OUTPUT INPUT R3 R1 100k 1k01 OV Fig. 11a Non -inverting, high input -impedance, Fig. Non x 100 d.c. 10a -inverting amplifier. x 100 a.c. amplifier. potentiometer and connecting the pot slider to the inverting terminal of the op -amp, as shown in the circuit DRIFTING INTO STABILITY Fig. varied of 10b The gain of this circuit can be over A useful development of the Fig. 1 1 a circuit is R,. the range x1 to x100 via shown in Fig. 1 1 b. Here, the values of R, and R2 are increased and a blocking capacitor ¡s interposed ... AND RESISTANCE TO INPUTS between them At practical operating frequencies this A major advantage of the non -inverting d.c. amplifier capacitor has a negligible impedance, so the voltage is that it has a very high input resistance. In theory, the gain is still determined by the ratios of the two resistors. input resistance is equal to the open -loop input Because of the inclusion of the blocking capacitor, resistance (typically 1 M) multiplied by the open -loop however, the inverting terminal of the op -amp is voltage gain (typically 100 000) divided by the actual subjected to virtually 100% d.c. negative feedback circuit voltage gain. In practice, input resistance values from the output terminal of the op -amp, and the circuit of hundreds of megohms can readily be obtained. thus has excellent d.c. stability. The low end of R3 is ETI July 1983 - 105 PRACTICE, AND ITS LIMITS OP-AffiP In practice the output of the basic Fig. 12a circuit will follow the input to within a couple of millivolts up to magnitudes within a volt or so of the supply line potentials. If required, the circuit can be made to follow COOKBOOK to within a few microvolts by adding the offset null facility to the op-amp. connected to the C3-R, junction, rather than directly to The d.c. voltage follower can be adapted for a.c. use the ground line, and the signal voltage appearing at this by wiring blocking capacitors in series with its input and point is virtually identical with that appearing at the output terminals and by d.c.-coupling the non non -inverting terminal of the op -amp -inverting terminal of the op -amp to the zero volts line via a suitable resistor, as shown by R, in Fig. 1 2b. R, should +9V have a value less than a couple of megohms, and C2 7 Opl restricts the available input impedance of the voltage Cl follower. Op1 H LACED UP R2 OHMS 1M If a very high input -impedance a.c. voltage follower is needed, the circuit of Fig. 12c can be used. Here, RI OUTPUT is boostrapped from the output of the op -amp, and its (NON C3 apparent impedance is greatly increased. This circuit INPUT POLARISED/ 2p2 has a typical impedance of hundreds of megohms. +9v R1 10k 1 C2 7 Opl Cl Op1 0-1 Fig. 11b Non -inverting x 100 a.c. amplifier. OUTPUT Consequently, identical signal voltages appear at INPUT R1 both ends of 1:13, and the apparent impedance of this 1M resistor is increased close to infinity by bootstrap action. This circuit thus has good d.c. stability and a very ov high input impedance In practice, this circuit gives a typical input impedance of about 50M. Fig. 12b a.c. voltage follower. VOLTAGE FOLLOWER PROJECTS (Figs. 12 to 13). A 741 can be made to function as a precision C2 voltage follower by connecting it as a Opt unity -gain Cl non -inverting amplifier. Fig. 12a shows the practical connections for making a d.c. voltage follower. Here, Fo the input signal is applied directly to the non -inverting terminal of the op -amp, and the inverting terminal is connected directly to the output, so the circuit has OUTPUT 100% d.c. negative feedback and acts as a unity -gain non -inverting d.c. amplifier. C3 2p2 The output signal voltage of the circuit is virtually INPUT identical to that of the input, so the output is said to 'follow' the input voltage. The great advantage of this circuit is that it has a very high input impedance (as high as hundreds of megohms) and a very low output impedance (as low as a few ohms). The circuit acts effectively as an impedance transformer. Fig. 12c Very high input -impedance a.c. voltage follower. DRIVING CIRCUITS AMP-LY The 741 op -amp is capable of providing output currents up to about 5mA, and this is consequently the current -driving limit of the three voltage follower circuits that we have looked at so far. The current -driving capabilities of the circuits can readily be increased by wiring simple or complementary emitter follower booster stages between the op -amp output O ovo terminals and the outputs of the actual circuits, as shown in Figs. 13a and 13b respectively. Fig. 12a d.c. voltage follower. Note in each case that the base -emitter junction(s) of 106 - July 1983 ETI the output transistor(s) are included in the negative Fig. 14 shows the circuit of a unity -gain inverting d.c. feedback loop of the circuit Consequently, the 600mV adder, which gives an output voltage that is equal to the knee voltage of each junction is effectively reduced by a sum of the three input voltages. Here, input resistors R, factor equal to the open -loop gain of the op -amp, so the to R3 and feedback resistor R4 each have the same junctions do not adversely effect the voltage -following value, and the circuit thus acts as a unity -gain inverting characteristics of either circuit. d.c. amplifier between each input terminal and the The Fig. 13a circuit is able to source current only, output. Since the current flowing in each input resistor and can be regarded as a unidirectional, positive -going, also flows in feedback resistor R4, the total current d.c. voltage follower. The Fig. 13b circuit can both flowing in R, is equal to the sum of the input currents, and thus gives source and sink output currents, and the output voltage is equal to the negative sum of the follower Each circuit has a bidirectional action. input voltages. The circuit is shown with only three input current -driving capacity of about 50mA This figure is connections, but in fact can be provided with any dictated by the limited power rating of the specified number of input terminals. The circuit can be made to can be increased output transistors. The drive capability function as a so-called 'audio mixer' by wiring blocking by using alternative transistors. capacitors in series with each input terminal and with the output terminal. Fig. 13a Unidirectional d.c. voltage follower with boosted Fig. 14 Unity -gain inverting d.c. adder, or 'audio mixer'. output (variable from OV to +8V at 50mA.) FIG. 15 shows how two unity -gain inverting d.c. amplifiers can be wired in series to make a precision unity -gain balanced phase-splitter. The output of the first amplifier is an inverted version of the input signal, and the output of the second amplifier is a non -inverted version. 91 1004 OUTPUT IINVEII TE OI INPUT OUTPUT 2 ININ INVENIEO1 Fig. 15 Unity gain balanced d.c. phase-splitter. Fig. 13b Bidirectional d.c. voltage follower with boosted output (variable from OV to± ±8V at 50mA). FIG. 16 shows how a 741 can be used as a unity -gain differential d.c. amplifier. The output of this circuit is equal to the difference between the two input signals or voltages, or to e, -e2. Thus, the circuit can also MISC AMP PROJECTS (Figs. 14 to 22) be used as a subtractor. In this type of circuit the Figs. 14 to 22 show a miscellaneous assortment of component values are chosen such that R,/R2=R4/R3, 741 amplifier projects, ranging from d.c. adding circuits in which case the voltage 1 The circuit to frequency -selective amplifiers. can thus be made to give voltage gain if required. ETI July 1983 - 107 amplifier, and may be altered to satisfy individual OP-AffiP needs. COOKBOOK R1 10k TO 10M (SENSITIVITY) 3 01 R1 100k R4 100k INPUT OUTPUT INPUT I 2 INPUT Cl 1 (SEE TEXT) Fig. 16 Unity -gain differential d.c. amplifier, or subtractor. VIN VI.V V/A' VIV rot 1R, N IOAIII (RI N /ouA11) (R, = 1,47111 (R, /01111 FIG. 17 50 n1V 500 mV 5V 50 V 2n5V shows the amp can be made to act as a 20 mV 200 nIV 2V 20 V 281 V non-linear (semi -log) a.c. voltage amplifier by using a 10 mV 100 mV IV 10 V 2 79 V couple 5 m 50111V 500 mV 5 V 2.60 V of ordinary silicon diodes as feedback elements. 2 mV 20 mV 200 mV 2 V 2 0.1 V The voltage gain of the circuit depends on the I mV 10 n1 100 mV I V IJYV 500 PV 5nIV 50111V 500 mV 0 ri`I V magnitude of applied input signal, and is high when 200 yV 2 n1V 20 mV 200 mV 0.a0V input signals are low, and low when input signals are I:UyV I nIV 10 mV 100 mV 0 20 V 50 PV 511112V 51nV 501.11/ 31111V high. The measured performance of the circuit is shown in the table, and can be varied by using alternative R, values. Fig. 18 Circuir and performance details of constant -volume amplifier. ACTION TAKEN The action of the Fig. 18 circuit relies on the fact that the JFET can act as a voltage -controlled resistance which appears as a low value when zero bias is applied to its gate and as a high resistance when its gate is negatively biased. The JFET and R3 act as a gain -determining a.c. voltage divider (via C2), and the bias to the JFET gate is derived from the circuits output via the D, -C, network. When the circuit output is low the JFET appears as a low resistance, and the op -amp gives high voltage gain. When the circuit output is high the JFET appears as a high resistance, and the op -amp gives low voltage gain. The output level of the circuit is thus held sensibly It, IkO RI constant by negative feedback. INPUT VOLTS IOYQ IRMSI . Ve.aiRMSI GAIN 1.RMSI GAIN 1 N 110 NV X110 71V XII IOW. 3JONV 7133 170NV X 17 IOOIN x50 NV XX 360NV x36 IV S60NV X056 x70NV X00 TOY ~NV X00) SLONV X0066 Fig. 17 Circuit and performance table of non-linear (semi -log) a.c. voltage amplifier. FIG. 18 shows how the 741 can be used together with a junction -type field-effect transistor (JFET) to make a so-called constant -volume amplifier. The action of this type of circuit is such that its peak output voltage is held sensibly constant, without distortion, over a wide range of input signal levels, and this particular circuit gives a sensibly constant output over a 30dB range of input signal levels. The measured performance of the circuit is shown in the table. C, determines the response time of the Fig. 19 1kHz tuned (acceptor) amplifier (twin -T). 108 - July 1983 ETI Finally, to complete this section, Figs. 21 and 22 CHOOSE YOUR FREQUENCY show the circuits of a couple of variable -frequency The 741 op -amp can be made to function as a audio filters. The Fig. 21 circuit' is that of a low-pass frequency -selective amplifier by connecting filter which covers the range 2.2kHz to 24kHz, and the frequency -sensitive networks into its feedback loops. Fig. 22 circuit is that of a high-pass filter which covers Fig. 19 shows how a twin -T network can be connected to the range 235Hz to 2.8kHz. In each case, the circuit the op -amp so that it acts as a tuned (acceptor) amplifier, gives unity gain to signals beyond its cut-off frequency, and Fig. 20 shows how the same twin -T network can be and gives a 2nd order response (a change of 12dB per connected so that the op -amp acts as a notch (rejector) octave) to signals within its range. filter. The values of the twin -T network are chosen such that R2=R3=2 x R and C2=: C4/2, in which case its INSTRUMENTATION PROJECTS (Figs. 23 to 31) centre (tuned) frequency =1/ 6.28 R2. C2. With the component values shown, both circuits are tuned to Figs. 23 to 31 show a variety of instrumentation approximately 1 kHz. projects in which the 741 can be used. The circuits range from a simple voltage regulator tó a linear -scale ohmmeter. R1 19k INPUT OUTPUT -9V RV1 R7 OUTPUT 1k 27k 0-12v SET NULL 0-50mA OV Fig. 20 1kHz notch (reject/ filter. Fig. 23 Simple variable -voltage supply. FIG. 23 shows the circuit of a simple variable -vol- Cl a that is 500P tage power supply, which gives stable output up to a R1 RV1 RV2 fully adjustable from OV to 12V at currents 10k 100k 100k maximum of about 50mA. The operation of the circuit is quite simple. ZD, is a zener diode, and is energised from -9V OUTPUT I GANGED line via R,. A constant reference INPUT the positive supply potential of 12V is developed across the zener diode, RV,. OV and is fed to variable potential divider The output of this divider is fully variable from OV to of the Fig. 21 Variable low-pass filter, covering 2.2kHz to 24kHz. 1 2V, and is fed -to the non -inverting input op -amp. The op -amp is wired as a unity -gain voltage follower, with Q, connected as an emitter follower current -booster stage in series with its output. Thus, the output voltage of the circuit follows the voltage set at the op -amp input via RV1, and is fully. variable from OV to 12V. Note that the circuit uses an 18V positive supply and a 9V negative supply. Also note that the voltage range of the above circuit can be increased by using higher zener and unregulated supply voltages, and that its current capacity can be increased by using one or more power transistors in place of Q. FIG. 24 shows how a 741 op -amp can be uséd as the basis of a stabilised power supply unit (P.S.U.) that covers the range 3V to 30V at currents up to 1 A. Here, the voltage supply to the op-amp is stabilized at 33V via ZD,, and a highly temperature -stable reference of 3V is fed to the input of the op -amp via ZD2. The op -amp and output transistors Q1 -Q2 are wired as a variable -gain non -inverting d.c. amplifier, with gain variable from unity to x10 via RV,, and the output voltage is thus fully variable from 3V to 30V via RV,. The Fig. 22 Variable high-pass filter, covering 235Hz to 2.8kHz. output voltage is fully stabilized by negative feedback. ETI July 1983 - 109 FIG. 26a shows how a 741 can be used in conjunction with a couple of silicon diodes as a OP -Amp precision half -wave rectifier. Conventional diodes act as imperfect rectifiers of low-level a.c. signals, because they do not begin to conduct significantly until the applied signal voltage exceeds a 'knee' value of about COOKBOOK 600mV. When diodes are wired into the negative feedback loop of the circuit as shown the 'knee' voltage is effectively reduced by a factor equal to the open -loop gain of the op -amp, and the circuit thus acts like a near -perfect rectifier. The overall voltage gain of the Fig. 26a circuit is dictated by the ratios of R, and R2 to R3, as in the case of a conventional inverting amplifier, and this circuit thus gives a gain of unity. The circuit can be made to OUTPUT 0-u3 30V R3 10k Fig. 24 3V - 30V, 0-1 amp stabilised p.s.u. AC FIG. 25 shows how overload protection can be INPUT applied to the above circuit. Here, HALFV'/AVE current -sensing Ve) resistor R is wired in series with the output of the OUTPUT regulator, and cut-out transistor Q3 is driven from this resistor and is wired so that its base -collector junction is able to short the base -emitter junction of the Q1 -Q2 output transistor stage. Fig. 26a Precision unity -gain half -wave rectifier. Normally, Q3 is inoperative, and has no effect on the circuit, but when P.S.U. output currents exceed lA a act as a precision half -wave a.c./d.c. converter by potential in excess of 600mV is developed across R, designing it to give a voltage gain of 2.22 to give and biases Q3 on, thus causing Q3 to shunt the form -factor correction, and by integrating its rectifier base -emitter junction of the Q1 -Q2 output stage and output, as shown in Fig. 26b. hence reducing the output current Heavy negative Note that each of the Fig. 26 circuits has a high feedback takes place in this and action, the output output impedance, and the outputs must current is automatically limited both be fed into to 1A, even under loads having impedances less short-circuit conditions. than about 1M. R1 1k 01 7 R5 2N3054 470R 2 2'43055 R1 10k R7 OR6 1w AC INPUT DC (0-2V RMS) OUTPUT -9V 10-2V) C1 R6 OUTPUT OV 470R 1009 3--30V 6D R4 0-1A VVP <7k7 Fig. 26b Precision half -wave a.c./d.c. converter. RV2 1k (SET 30V) FIG. 27 shows how op -amp can be used as a high-performance d.c. voltmeter converter, which can be used to convert any 1V f.s.d. meter with a sensitivity Fig. 25 3V - 30V stabilised p.s.u. with overload protection. better than 1k /V into a voltmeter that can read any 110 - July 1983 ETI value in the range 1 mV to 10V f.s.d. at a sensitivity of FIG. 30 shows the basic circuit of a precision a.c. 1M/V The voltage range is determined by the R, volt or millivolt meter. This circuit can be used with any value, and the table shows some suitable values for moving -coil meter with a full scale current value in the common voltage ranges. range 100uA to 5mA, and can be made to give any full scale a.c. voltage reading in the range 1 mV to 1000mV. The tables show the alternative values of R, FIG. 28 shows a simple circuit that can be used to and R2 that must be used to satisfy different basic meter convert a 1 mA f.s.d. meter into a d.c. voltmeter with sensitivities, and the values of R3 and R4 that must be any f.s.d. value in the range 100mV to 1000V, or into used for different f.s.d. voltage sensitivities. a d.c. current meter with any f.s.d. value in the range 1 uA to 1 A. Suitable component values for different ranges are shown in the tables. HOME OHM Finally, to conclude, Fig. 31 shows how the 741 Rt VIs4 op -amp can be used in conjuncton with a 1 mA f.s.d. 10V IOMO IV IMO meter to make a linear -scale ohmmeter that has five 100w 10ok Q 1 k to 10M. IOW 10k0 decade ranges from The circuit is divided into two parts, and consists of a voltage generator that is used to generate a standard test W1 SEE TABLE 1000mV R1 750k 250m V R2 1501 C / R3 CI 751 Fig. 27 High-performance d.c. voltmeter converter. O O 25mV SYvI 114 O O 1::\ lsk .9V 10mV R5 715 3 INPUT 2.5mV R6 115 1,nV RV1 10k (SET 2EROI R7 9V R1 O Fig. 29 Precision d.c. millivoltmeter. SEE INPUT TABLE VOLT ME TER CURRENT METER Is0 R, R 1s4 RI R7 1000V IOMO 110 IA 00 010 100V 10140 1010 100MA 00 IQ 10V 10MQ wain 10MA 00 100 IV 90010 10010 1MA 00 1000 100..V 00 10010 100RA on 110 1004A 00 10kQ M, R7 N 1MA 00 100161 '1 I00..Á 100 7n ta 1000v 10MO 10.0 wO,.A .00 5110 looV 100.0 100.0 Fig. 28 Simple d.c. voltage or current meter. lMA 5000 1 710 lOV IOMO 10.0 IV 10.(. 1SMA 1100 I 5.0 Mn 5W 1100 17m IOOMY 10000 10.0 10.0 a d.c. VAkuE5 F011 16E N.IM 1QN lobo FIG. 29 shows the circuit of precision O.FF ERE Nt MF TER .1ovE IW 11.0 IMO mil N15 millivoltmeter, which uses a 1 mA f.s.d. meter to read DIFFERENT 1. r01.T14F f.s.d. voltages from 1mV to 1000mV in seven SENS.Irol ES switch -selected ranges. Fig. 30 Precision a.c. volt/millivolt meter. ETI July 1983 - 111 OP-AffiP COOKBOOK Test Resistor Fig. 31 Linear -scale ohmmeter. voltage, and a readout unit which indicates the value of the resistor under test. The voltage generator section of.the circuit comprises zener diode ZD,, transistor Q,, and resistors R, to R4. Fig. 32 150Hz - 1.5kHz Wien -bridge oscillator. The action of these components is such that a stable reference potential of 1V is developed across R4, but is adjustable over a limited range via RV,. This voltage is fed to the input of the op -amp readout unit. The op -amp is wired as an inverting d.c. amplifier, with the 1 mA and RV3 forming a 1V f.s.d. meter meter across its Fig. 33 shows how either a 741 or a 709 op -amp output, and with the op -amp gain determined by the can be connected as a simple variable -frequency values of ranging resistors R5 to R9 and by negative square -wave generator that covers the range 500Hz to feedback resistor R.. 5kHz via a single variable resistor. (The circuit produces Since the input to the amplifier is fixed at 1V, the a good symmetrical waveform.) output voltage reading of the meter is directly The frequency of oscillation is inversely proportional proportional to the value of R., and equals full scale to the C, value, and can be reduced by increasing the when R. and the ranging resistor values are equal. C, value, or vice -versa. The amplitude of the square Consequently, the circuit functions as a linear -scale wave output signal can be made variable, if required, ohmmeter. by wiring a 10kS2 variable potential divider across the output terminals of the circuit and taking the output from between the CALIBRATION pot slider and the zero volts line. The procedure for initially calibrating the Fig. 31 circuit is as follows: First, switch the unit to 10k range and fix an accurate 10k12 resistor in the R. position. Now adjust RV, to give an accurate 1V across R,, and then adjust RV 2 to give a precise full scale reading on the meter. All adjustments are then complete, and the circuit is ready for use. MISCELLANEOUS 741 PROJECTS The 741 op-amp can be used as the basis of a vast range of miscellaneous projects, including oscillators and sensing circuits. 500Hz FIG. 32 shows how the 741 op -amp can be connected as a variable -frequency wien-bridge oscilla- OUTPUT tor, which covers the basic range 1 50Hz to 1.5kHz, and uses a low -current lamp for amplitude stabilisation. The output amplitude of the oscillator is variable via RV, and has a typical maximum value of 2.5V r.m.s. and a t.h.d. value of 0.1%. The frequency range of the circuit is inversely proportional to the C1 -C2 values The circuit can give a useful performance up to a maximum frequency of about 25kHz. Fig. 33 Simple 500Hz - 5kHz square wave generator. 112 - July 1983 ETI The op -amp cookbook using the LM 3900N Four op -amps in a single 14 -pin package - at less than 25 cents per amplifier. THESE days it's nothing unusual to find two voltages (as in a conventional INPUT 3. INPUT 4- OUTPUT 3 four op -amps in a single integrated amplifier). V. INPUT 4 4 INPUT circuit package, but when the LM3900 The type of amplifier used in the OUTPUT 3- was released by National Semicon- LM3900N may be referred to as a 14 10 9 ductor in the mid -seventies very few 'Norton' amplifier, since Norton is the linear devices were so closely -packed. name of the person who developed a The LM3900 contains four independent, theorem relating the current flowing in internally compensated amplifiers in a a circuit to the equivalent current single 14 -pin dual -in -line encapsulation. generator and shunt impedance. All four amplifiers are fabricated on a single silicon chip. Each amplifier contains seven transistors, a diode and a capacitor, whilst other internal com- ponents are used in the bias and power supplies. Fig. 1. The connections of the LM3900N. The LM3900 has maintained its popularity over the years, partly 5 7 because of its low cost (less than a dollar in 1982), but mainly because of its INPUT 1 INPUT 1- OUTPUT 1 GNO versatility and reliability. INPUT 2. OUTPUT 1 INPUT 1- INVERTING CONNECTIONS INPUT Fig.2. The symbol for The connections of the four separate one of the OUTPUT Norton amplifiers are amplifiers shown in Fig.1. Each NON -INVERTING of the LM3900N. amplifier has a non -inverting input INPUT (marked +), an inverting input (marked -) and an output connection. In addition, there is a single common positive supply connection and a SYMBOL PERFORMANCE ground common connection (negative The symbol recommended for each The LM3900N has the advantage supply line) for the whole device. of the four Norton amplifier stages in that it can operate from a single is Fig.2. the device shown in This supply voltage over the range of four INTERNAL CIRCUIT symbol distinguishes this type of volts to 36 volts. Most conventional Conventional high gain amplifiers amplifier from the standard operational amplifiers require súpplies employ a differential input stage to operational amplifier symbol and symmetrical with respect to ground provide inverting and non -inverting avoids confusion in circuits. (typically ± 15 V); the LM3900N can inputs, but a rather different approach The symbol of Fig. 2 contains an be used with such supply lines if is employed in the LM3900N. A indication that there is a current desired. 'current mirror' is employed in the source between the inverting and non -inverting input circuit, the current non -inverting inputs and implies that The maximum poak to peak output 'reflected' in this mirror being the amplifier uses a current mode of amplitude of an LM3900N amplifier is subtracted from that which enters the operation. In addition, the circuit only 1 V less than the supply voltage inverting input. symbol indicates that current is employed. The current consumed This type of amplifier therefore acts removed from the inverting input, from the power supply is typically 6.2 as a differential stage by amplifying whilst the arrow on the non -inverting mA (maximum 10 mA). the difference between two currents input shows that this functions as a The typical voltage gain of each rather than the difference between current input. amplifier is 2800 or nearly 70 dB. The ETI July 1983 - 113 R2 1MS1 120 741 OP AMP 100 INPUT BO Cl O.OSVF am LM3900N Z 60 Q O 40 O R L 104 S FOR 20 - BOTH AMPLIFIERS O 1 I 106 1M 10M 1 10 100 16 Fig.4. A simple a.c. amplifier circuit. R3 1M!! Frequency (Hal Fig. 3. Comparison of the gain of the LM3900N with that of a 741 amplifier at various frequencies. minimum gain of any amplifier is 1200. The variation of this gain with frequency is compared with that of the well known type 741 operational amplifier in Fig. 3. It can be seen that the LM3900N amplifiers provide R2 NW` 1MSt about 10 dB more gain at all frequencies above 1 kHz. APPLICATIONS C2 RS The Norton amplifiers used in the 5165! LM3900N device entail the use of somewhat different circuit design techniques than those used with conventional operational R3 R4 amplifiers. Fig.5. A simple non -inverting a.c. amplifier. The inverting input of the LM3900N IM5! 1M5í amplifiers must be supplied with a steady biasing current. The current to the non -inverting input modulates that to the inverting input. The fact that current can pass between the input terminals leads to some unusual applications. Both inputs of each of the amplifiers INPUT in the LM3900N are clamped by diodes so as to keep their potentials OUTPUT almost constant at one diode voltage drop (about 0.5 V) above the ground potential of pin 7. External input voltages must therefore be converted to input currents by placing series resistors in each input circuit. vr2 Fig.6. An amplifier which has a high gain and a high input impedance. USE AS AN AC AMPLIFIER The LM3900N forms a useful ac amplifier, since its output can be baised to any desired steady voltage within the range of the output voltage swing. The ac gain is independent of R2 the biasing level and the single power 5.16!! supply required greatly simplifies C, circuit design. R1 100411 A simple ac amplifier circuit is shown INPUT in Fig.4. The gain is approximately D, equal to R2/R1 or 10 with the circuit D2 values shown. The mean potential at RS CONTROL 10651 the output is half the supply voltage. áVOL NTA cE The value of R3 should be twice that of R6 R2 since the current passing through 14SS each of these two resistors is then the same. The positive supply and ground connections are not shown in Fig.4 F. g.7. An amplifier which has a gain controlled by an input voltage. 114 - July 1983 ETI divided by the current passing through R2 to the non -inverting input. The capacitor values should be chosen so that the impedance of these components is considerably less than Fig.8. A direct the circuit impedance at the points coupled power concerned. amplifier. HIGH IMPEDANCE AND HIGH GAIN The circuits of Figs. 4 and 5 have an input resistance, R1 or 100 k ohm. If this resistor is increased to provide a higher input impedance, the gain of the circuit will fall. However, the circuit of Fig. 6 has been designed so Rx that it provides both a high input 3MS1 impedance and a high gain using a Cl OUTPUT simple amplifier. With the component o.oxuP values shown, the input impedance is one megohm and the gain 100. The voltage applied to R2 is made R3 Rd equal to the output voltage (which is IOMS 10MSt V. 'VVv^ half the supply voltage). The value of R2 is equal to the sum of R3 and R4; Fig.9. A simple square -wave generator. these resistors set the dc bias. If desired, R2 may be made four megohms and its lower end connected R1 1619 1C1 to the V4 supply. 0.00115 Resistors R4 and R5 form a potential OUTPUT 1 divider so .that only 1/100 of the alternating output voltage is developed R3 across the C2 - R5 circuit. This 10014? /WA fraction of the output voltage is fed INTEGRATOR back to the inverting input via R3.,As R1 is SCHMITT TRIGGER OUTPUT 2 R3 and are equal, the gain R4 R5. As R5 is decreased, the gain R2 siait approaches the open loop gain of the amplifier. Rd VOLTAGE CONTROLLED GAIN An amplifier with a gain which can be controlled by the value of a steady applied voltage is shown in Fig. 7. Fig. 10. A circuit for generating triangular and square -wave. A current flows from the positive supply through R3 to provide a bias which prevents the output of the amplifier from being driven to RI saturation as the control voltage is INTEGRATOR varied. When D2 is non -conducting, 1 the currents ipassing both R2 CONTROL OUTPUT through VOLTAGE R and R3 enter the non -inverting input and the gain is of maximum. This occurs when the control voltage TR, approaches 10 V. The gain is a minimum when the control voltage is zero. In this case D2 OUTPUT 2 is conducting and only the current 6 R3 the V passing through enters RV V V non -inverting input of the amplifier. SCNMITT TRIGGE Fig. 11. A voltage controlled oscillator which produces triangular and square -waves. DIRECT COUPLED POWER AMPLIFIER for simplicity, but R3 should be NON -INVERTING AC AMPLIFIER In the circuit of Fig. 8, the output returned to the same positive supply The circuit of Fig. 5 shows an from an LM3900N amplifier is fed to a line as that used to feed pin 14. amplifier which provides an output in Darlington pair of power transistors. The circuit of Fig. 4 provides a phase phase with the input. The gain is equal This circuit can deliver over three inverted output. Any ripple on the to R3/(R1 + rd) where rd is the small amps into a suitable load when the power supply line will appear on the signal impedance of the input diode. transistors are correctly mounted on output at half amplitude. The value of rd is equal to 0.026 heat sinks. ETI July 1983 - 115 Fig. 11. As in Fig.10, one amplifier is Fig. 12. A voltage employed as an integrator. comparator with When the output of the Schmitt ?,.,... i an indicator lamp. trigger is high, the clamp transistor TR1 is conducting and the input current passing through R2 is shunted CI to ground. The current passing 0.05µF R1 through Rt INPUT 111 causes a falling ramp to be u".t R! formed. 10041t When the Schmitt circuit changes state, its output switches TR1 to the non -conducting state. The current V AMPLIFIER 1 R2 flowing through R2 can be made twice 1M!t that flowing through R1 (R2 = R1/2) so that the rising part of the ramp has 5j a 1 R7 similar slope to the negative part. 1oM:t The greater the value of the control voltage in Fig.11, the greater the 10M! t frequency of oscillation. However, the C2 0.05µF INPUT (31 voltage must exceed the constant input voltage (VgE or the circuit will fail to oscillate. R6 S.IM!t VOLTAGE COMPARATOR AMPLIFIER 2 OUTPUT The circuit of Fig. 12 shows how an LM3900N amplifier may be employed to compare two input voltages and to indicate the result by means of a small R11 lamp. If the input voltage 10M!2 TOM!! connected --MM- to the non -inverting input is appreciably more positive than the C3 0.05µF R9 other input, the output of the 1ooklt INPUT 131 amplifier will provide a positive voltage which renders TR2 conducting. The lamp will then be illuminated. AMPLIFIER 3 One of the inputs may be a reference voltage so that one can then compare a single input voltage against 53 this \ constant reference. Fig. 13. An audio mixer unit. AUDIO MIXER SQUAREWAVEGENERAATOR When the output voltage from the The amplifiers of a LM3900N device The multiple amplifiers in the Schmitt trigger circuit is low, the can be conveniently used to make a LM3900N device are very suitable for current flowing through R2 is mixer unit for audio purposes; the unit use in waveform generators at integrated by Ct to produce the enables three separate audio signals to frequencies of up to about 10 kHz. negative slope of the triangular wave at be mixed together to produce a Voltage controlled oscillators (the output 1. When the output 2 voltage composite output. The circuit shown frequency of which is dependent on an from the Schmitt trigger is high, in Fig. 13 provides this facility using input voltage) can also be designed current flows through R2 to produce only a single LM3900N device and also using the device. the rising part of the waveform at enables any one channel to be selected A simple square wave generator is output 1. by switches. The currents passing shown ín Fig. 9. The capacitor Ct The output waveform will have good through the resistors R4 Rg and R12 alternately charges and discharges symmetry if Rt = 2R2. The output are summed in the input circuit of the between voltage limits which are set frequency is given by the equation: fourth amplifier. by R2 R3 and R4. The circuit is If Si is open, amplifier 1 will be basically of the Schmitt trigger type, driven to saturation by the current f = V'-VBE the voltages at which triggering occurs passing through R2. It will therefore 2R being approximately V+/3 and 2V+/3. CIV be inactive. where Rt - 2R2, VBE is the steady CONCLUSION TRIANGULAR WAVEFORM voltage at the inverting input (0.5 V) This short article has attempted to GENERATOR V is and the difference between the show a few of the numerous A triangular waveform generator can tripping points of the Schmitt trigger. applications of this economical be made by using one amplifier of a integrated circuit. Many more LM3900N device as an integrator and applications (such as phase locked another amplifier as a VOLTAGE CONTROLLED Schmitt trigger loops, temperature sensing circuits, circuit. A suitable circuit is in shown OSCILLATOR differentiators, tachometers, staircase Fig. 10; it has the unusual advantage A simple voltage controlled oscillator generators, active filters, etc) are given that only the one power is supply circuit which produces both triangular in a report AN -72 required. produced by and square wave outputs is shown in National Semiconductor. 116 - July 1983 ETI The op -amp cookbook using the 3080 A 'control' current varies the gain of this op -amp, which makes it very useful in some special applications. THE CA3080 IS KNOWN as an opera- 10k (R5), but this is 'unloaded' by the This type of tional circuit is known by transconductance amplifier voltage follower (IC2) to produce a low several names. It is a voltage (OTA). controlled This is a type of op -amp, the gain output impedance. amplifier; (VCA), or an amplitude of which can be varied by means of a The circuit involving IC3 is a pre- modulator, or a two quadrant control current, (IAw). The device has a cision voltage -to -current converter and multiplier. differential input, a control input this can be used to generate IARC. When One occurs with known problem that the as the 'amplifier bias input' and Vin (control) is positive, it linearly CA3080 is that of the 'input offset a current output. It differs in many re- controls the gain of the circuit. When it voltage'. This is a small voltage diffe- spects from conventional op -amps and it is negative, IAac is zero and so the gain is these differences that can be used to is zero. realise many useful circuit blocks. Voltage controlled amplifier The CA3080 can be used as a gain con- SIGNAL trolling device. A useful circuit is shown INPUT in Figure 1. The input signal is attenu- 2Vpp l. ated by Rl, R2 such that a 20 mV peak - to -peak signal is applied to the input /1 /1 terminals. If this voltage is much -,_O OUTPUT larger, then significant distortion will occur at the output. In fact, this distor- tion is put to good use in the triangle-to- RV1 sinewave 100k converter. (Figure 3, but we're CONTROL jumping the gun). BREAKTHROUGH The gain of the circuit is controlled by ADJUST the magnitude of the current IABC This current flows into the CA3080 at pin 5, which is held at one diode voltage drop LINK above the -Vcc rail. If you connect pin 5 to 0 V, then this diode will get zapped (and so will the IC!). The maximum value of IABC permitted is 1 mA and the R7 device is 'linear' over four decades of 10k this current. That is, the gain of the CA (! 1 Vin (CONTROL) BC 182 3080 is 'linearly' proportional to the OV TO .5V max magnitude of the IABC current over a range of 0.1 uA to 1 mA. Thus, by controlling IARC, we can control the signal level at the output. The output is a current output which has to be 'dumped' into a resistive load Figure 1. A voltage controlled amplifier. Gain is varied by varying RV1. You can modulate a signal passing (R5) to produce a voltage output. The through the amplifier by joining the 'link' and applying a modulating signal to the input of IC3 (at R7). This output impedance seen at IC1 pin 6 is sort of circuit is also known as a 'two quadrant multiplier'. ETI July 1983 - 117 oP-AmP COOKBOOK OUTPUT SIGNAL f INPUT OV Vin ¡ OV CONTROL ^ OUTPUT f UNDER + INPUT DISTORTED OV OUTPUT qinggi'ri' Figure 2. Illustrating the operation of the voltage controlled amplifier shown in Figure 1. OVER - TRANSFER rence, or `offset', between its input DISTORTED FUNCTION terminals. When there is no signal in- Figure 5. Transfer function of the Figure 3 circuit. put and the control input is varied, a voltage similar to the control input will By adjusting RV1 appear at the output. Figure 4. The output of the Figure 3 circuit should it is possible to null out most of this be adjusted (by RV1) to produce the waveform control breakthrough. shown at top. The effect of modulating Vin (control) is illustrated in Figure 2. I ABC PROTECTION Triangle to sinewave f RESISTOR converter R1 10k of a CA3080 it By overloading the input V OUT -4-- is possible to produce a `sinusoidal' transfer function. That is, if a triangle is 5 Figure 7. How the Schmitt trigger of Figure 6 waveform of the correct magnitude works. applied to the CA3080 input, the output Vin CA3080 V OUT will be distorted in such a way as to POWER FROM is produce a sinewave approximation. _ 12V The result of varying RV1 illustrated in Figure 4 and the transfer POWERED FROM t 12V INPUT function of the circuit is shown in Figure 5. R1 /".\\/,"\\ 10k R2 10k Schmitt trigger 4Vpp Most Schmitt trigger circuits prove to be very complicated when it comes to calculating the hysteresis levels. However, by using the CA3080 these + V OUT calculations are rendered trivial, plus there is the added bonus of fast operation. The hysteresis levels are cal- DISTORTION ADJUST culated from the simple equation, VHYST = +/- (Luc X R2) will a triangle wave to Figure 3. This circuit convert + Vin a sinewave with a resultant distortion of around The output squarewave level is in fact 1.8%. equal in magnitude to the hysteresis is as In the circuit shown (Figure 3), RV 1 is levels. The circuit operation adjusted so that the output waveform follows (referring to Figure 7): resembles a sinewave. I tested this Imagine the output voltage is high. circuit using an automatic distortion The output voltage will then be equal to (R2 x IABc) which we will call + VHYST. analyser and found the sinewave distor- If HYSTERESIS tion to be only 1.8%, mostly third If VIN becomes more positive than harmonic distortion which, for such a +VHYST, the output will start to move in IABC CONTROLS HYSTERESIS a negative direction, which will in- simple arrangement, seems very LEVELS AND OUTPUT LEVEL reasonable indeed. This could be used to crease the voltage between the input Figure 6. This sort of Schmitt trigger is not only terminals which will further accelerate produce a sinewave output from a simple but you can specify the hysteresis levels triangle/square wave oscillator. as well! the speed of the output movement. This 118 - July 1983 ETI ---0,. 12V 01 R3 BC182 6k8 ALL POWERED FROM! 12V 6 INPUT (>--"A/V- RI -5Vto+5V 56k ICI 0.5mA R5 max 680k R2 1k > R4 10k - 12V R6 27k // tí IN4148 I ABC 5 3 3 + 6 5 1.5V CA3080 Í+ 3 6 CA3080 2 741 IC3 2 - 1.5V IC2 NEEDS A BUFFER 1C4 Figure 8. This voltage controlled oscillator has a square and a tri- angle output. By varying the Input Cl al 3k9 between -5 V and +5 V, the output ton frequency can be varied over the range 10 Hz to 10 kHz. Note that 01 and Q2 should be a matched pair. APROXIMATELY 10kHz FOR lAec -0.5mA 10Hz FOR I ABC =0.5uA is known as regenerative feedback and is responsible for the Schmitt trigger action. The output snaps into a negative state at a voltage equal to -(R2 x IAsc) One CA3080, IC2, is an integrator. The larger the current, the faster the which is designated as -VHYST. Only The IARC current that drives this IC is capacitor is charged and discharged. when VIN becomes more negative than used to either charge or discharge Cl. Two outputs are produced, a triangle -VHYST will the output change back to This produces triangular waveforms wave (buffered) from IC3 and a square - the +VHvsT state. which are buffered by IC3, which then wave (unbuffered) from IC4. If the The Schmitt trigger is a very useful drives the Schmitt trigger IC4. The squarewave output is loaded, then the building block for detecting two discrete hysteresis levels for this device are oscillation frequency will change so a voltage levels and finds many uses in fixed at +/-1.5 V, being determined by buffer is advisable. circuit designs. R6 and R7. Vc Voltage The output of the Schmitt trigger is controlled oscillator fed back in such a way as to control the 5 By using two CA3080s and some 741 direction of motion of the integrator's 4 op -amps it is possible to make an output. If the Schmitt output is high, oscilla- .3 tor, the frequency of which is voltage then the integrator will ramp upwards controllable. This unit finds many and vice versa. 2 applications in the fields of electronic Imagine that the integrator is ramp- .1 music production and test ing upwards. When the integrator's FREQUENCY equipment. 0 The circuit (Figure 8) been output reaches the upper f Í f has given hysteresis ó 10Hz 100Hz 1kHz .10kHz LOG a logarithmic control law, that is, the level, the Schmitt will flip into its low -1 frequency of operation doubles for every state, and the integrator will start to -2 volt increase in the control voltage. This ramp downwards. When it reaches the -3 makes it ideal for musical applications low hysteresis level the Schmitt will flip where linear control voltages need to be back into its high state. Thus the inte- -4 converted into musical intervals (which grator ramps up and down in between -5 are logarithmically spaced) and also for the two hysteresis levels. -Vc LOG CONTROL LAW audio testing where frequencies are The speed at which it does this, and generally measured hence as logarithmic the oscillating frequency, is de- Figure 9. Voltage versus frequency characteristic functions. termined by the value of IARC for IC2. of the Figure 9 circuit. ETI July 1983 - 119 OP-AmP COOKBOOK Vin The log. law generator is composed of Ql, 2, 3 and IC1. Transistors Q1 and Q2 Van should be matched so that their base Vref 13Viusec emitter voltages (Vbe) are the same for (50uA). LESS THAN the same emitter current, 4V WRT V ,et Matching these devices to within 5 mV is satisfactory, although unmatched and finishing on axis crossings of the Vout pairs could be used. When matching sinusoid. The CA3080 is configured transistors, take care not to touch here as a voltage comparator, used tó them with your fingers. This will detect these axis crossings and to pro- heat them up and produce erroneous duce a square wave output which then R3 measurements. drives a binary divider (IC3). The 10k Transistor Q2 is used to produce a divider produces a 'divide by sixteen' reference voltage of about -0.6 V, output which is high for eight sinewave which is connected to IC1 pin 3. This cycles and then low for the next eight. op -amp and Q3 is used to keep the This signal is then used to gate ON and emitter of Q1 at the same voltage of OFF the sinewave. -0.6 V. The input control voltage is The gate mechanism is a pair oftran- attenuated by Rl, R2 such that a +1 V sistors which short the sinewave to a is increase at the input produces change ground when the divider output high Figure 10. Example of a fast comparator. of only +18 mV at the base of Q1. How- and let it pass when the divider output ever, the emitter of Q1 is fixed at is low. The resulting output is a -0.6 V, so the current through Q1 toneburst. doubles. (It is a property of transistors However, if the comparator is not that the collector current doubles for every 18 mV increase in Vbe). The emitter current of Ql flows through Q3 and into IC2, thus con- is R4 R5 trolling the oscillator frequency. It 10k 8k2 possible to get a control range of over POWERED BY ! 6V 1000 to 1 using this circuit. With the values shown, operation from 10 Hz to kHz is achieved. Reducing Cl to In CA3080 CK 1C3 10 C04024 will increase the maximum frequency 31 RESET to 100 kHz, although the waveform IC2 may be somewhat degraded. quality SINE Changing Cl to luF, (non -polarised) WAVE a minimum frequency of INPUT will give 2Vpp 0-41 0.1 Hz. Fast comparator R6 R7 8 CYCLES ON 10k 10k 8 CYCLES OFF The high slew rate of the CA3080 makes UP TO 20kHz it an excellent fast voltage comparator i and a circuit is shown in Figure 10. When pin 2 of IC1 is more positive than Vref, the output of IC1 goes negative and vice versa. Vref can be moved around so that the point at which the output changes can be varied. As long as the input sinewave level is quite large (1 V say) then the output can be made to move at very fast rates indeed. How- ever, care must be taken to avoid overloading the inputs. If the differen- tial input voltage exceeds 5 V, then the TONE BURST GENERATOR input stage breaks down and may cause Figure 11. A fast compara- an undesired output to occur. tor is used in this tone burst a is in a generator, producing eight One use of fast comparator cycles of tone with eight tone burst generator. A circuit is shown cycle breaks starting and -1, L l.. 11. device produces finishing at on -axis in Figure This OFF ON bursts of sinewaves, the burst starting crossings. ON 120 - July 1983 ETI +12V very fast then there will be a delay in generating the gate and so the tone burst will not start or finish on axis crossings. POWERED FROM ± 12V SLEW LIMITED OUTPUT Using the circuit shown, operation up to 20 kHz ís obtainable. 7 1C2 Slew limiter The current output of a CA3080 can be used to produce a controlled slew limiter. By connecting the output current to a capacitor, the output voltage -cannot move faster than a rate given by Slew Rate = IABc Volts per sec. Cl Note that IABC determines the slew rate and as IABC is a variable then so is the slew rate. A suitable circuit is shown in Figure 12. The output voltage is buffered by a voltage follower, IC2. This is a - 12V MOSFET op -amp which has a very high input impedance, which is necessary to minimise the loading on Cl. When an input signal is applied to IC1 the output tries to move towards this voltage but its speed is limited by the slew rate. Thus, the output produces a linear ramp which stops when it Figure 12. This slew rate limiter circuit produces a linear ramp on signals which exceed the slew rate limit, the output amplitude stopping when it reaches the signal level. reaches the input signal level. Sample and hold 12V POWERED FROM t 12V A typical application of the slew limiter circuit is in a sample and hold circuit. C2 J.. SLEW RATE 100n T The circuit in Figure 13 could be termed 3V/mSac an analogue memory. When the control INPUT O + IC, 3 voltage is high, the circuit will 're - CA3080 OUTPUT 2 3 2 member' or'hold' the input voltage level 5 CA 1140 _9 6 } present at the time. The result is shown %(4 I in Figure 14. OUTPUT SUPERIMPOSED 0.3V=HOLD UPON THE INPUT 3.5V=SAMPLE CONTROL R2 INPUT R1 10k VOLTAGE 10k PNP BC212 SAMPLE C3 Cl 100n .."." 100n CONTROL - 12V HOLD R3 10k R4 10k - 12V OUTPUT «JI/ Figure 14. Illustrating the operation of the sample Figure 13. A typical application of the slew rate is limiter this sample and hold circuit. and hold circuit of Figure 13. ETI July 1983 - 121 OP-AffiP COOKBOOK X INPUT In this circuit, IABC is either hard ON POWERED FROM ± 12V (sample) or completely OFF (hold). In mode, the output voltage RV1 the sample 10k R4 quickly adjusts itself so that it equals R1 100k the input voltage. This enables a short 10k period to be used. R3 sample IC1 10k In the HOLD mode, IA jc is zero and so 2 IC2 XV OUTPUT the voltage on Cl should remain fixed. CA3080 3 Such circuits are used in music 741 o) synthesizers (to remember the pitch), in 3 + analogue -to-digital converters and many other applications. 5 R2 A multiplier/modulator R5 100R 47k The CA3080 is basically a two - quadrant multiplier, that is, it has two inputs, one of which can accept bipolar signals (positive and negative going) - the inverting or the non -inverting input L Ic3 other can only accept a unipolar Y INPUT 2 - the 741 signal - the control input, pin 5. o 3 + 6 Whilst a two -quadrant multiplier is very useful in a wide variety of appli- cations, a four -quadrant multiplier has R6 extra advantages. For example, apart 47k from amplitude modulation, it can perform frequency doubling and ring modulation. See Figure 16. Now, a four - quadrant multiplier has two inputs, both of which can accept bipolar signals. An example of a four -quadrant multi- Figure 15. This multiplier/modulator can be used to produce a 'Dalek' voice when working as a ring plier is a frequency converter in a radio modulator. It can also be used as a frequency doubler. receiver. The familiar diode ring mixer A 741 op -amp, IC3, is used to generate Amplifiers" (second edi- is another example of a four -quadrant "Operational IABC in such a way that its input, the 'Y' tion), by G.B. Clayton, published by multiplier. input, can go both positive and negative. Newnes-Butterworths. in Figure 15 is fairly The circuit Thus, the Y input is bipolar. to two similar that of the -quadrant When Y is at zero volts (no input) and in Figure 1. This cir- multiplier shown there is a signal on the X input the de- differences. cuit has several important sired output (X x Y) should be zero. This is achieved by adjusting RV1 so that the Single pole filter/wah wah OV %VINPUT$ signal via IC1 (this is inverted) is Thé guitar 'wah wah' effects unit 2F exactly cancelled out by that via R3. employs a filter which can be manually is OV IMNIAU Now, when Y increased positively, a 'swept' across the middle of the audio XV OUTPUT non -inverted value of X is produced at frequency range, generally from around FREOUENCV DOUBLING the output and, when Y is increased 500 Hz to 5 kHz or so, producing the negatively, an inverted value of X is peculiar 'wah wah' sound. B INPUT produced. When Y is zero, so is the out- A single pole, voltage -controlled, low F1,1111VIÜIll I n1111 11111 Ilil. dhl enIIIIII put. This is known sometimes as ring pass filter can be constructed using a modulation. CA3080 as a current -controlled re- If a speech signal is connected to the X sistor. The circuit is showh in Figure 17. Y INPUT input and an audio oscillator to the Y A simple, low pass RC filter configu- input, the resulting sound is that of a ration is employed, the controllable 'R' 'Dalek'. is the CA3080 and the 'C' is Cl. Varying ( Also, if a sinewave is connected to IABC varies the amount of current drive XV OUTPUT both the X and Y inputs, the XY product to Cl. This circuit configuration would is a sinewave of twice the frequency. normally be a slew limiter, except that This is known as a frequency doubler, the signal level to the input of the it will only work with sinewaves. is low (Rl and RING MODULATION but CA3080 kept deliberately For more theoretical information on R2 form a 100:1 attenuator) so that the Figure 16. Illustrating the various operations of the four -quadrant multipliers, especially IC operates in its linear mode. This en- four quadrant multiplier of Figure 15. the variable transconductance type, see ables it to look like a variable resistor. 122 - July 1983 ETI LINK Vcc 12V When this resistor is varied, the break RV1 (3-9.- 10k frequency of the filter also varies. R3 lin POWERED FROM 1121/ I ABC MANUAL By applying some positive feedback 68k CONTROL around the filter (R6, C2) it is possible to NPUT produce a peaky filter Vpp D1 response. The IN4148 peak actually increases with frequency, C 3iT producing the wah wah effect. - Vcc - 12V R1 CA3080 The circuit as shown be 10k OUTPUT can swept 21_ 3 + 6 from about 400 Hz at the lower 741 O) extreme 2 _ to about 4 kHz at the upper extreme. See Figure 18. Cl OUTPUT 470p INPUT - WITH POSITIVE R2 FEEDBACK 100R R4 RS 100R 10k - 61B/OC TA VE POSITIVER610 FREQUENCY FEEDBACK 400Hr SkH, C2 Figure 18. How the single pole filter affects the 10n LINK frequency response of the signal passed through the wah wah unit. Figure 17. A guitar wah-wah unit can be made with 1 ABC a swept frequency single pole filter. I(max 0.5mA1 POWERED FROM t 12V R3 R7 INPUT RI 10k 180k 10k 3r+ BAND PASS @--I BP CA3090 6 Cl + + 3 LP 100n 741 CA3080 PASS 2 O LOW ICI 7 41 O 2 IC2 1C3 1C4 C2 2n2 Ra 27k + C3 """' 2n2 RS 270R R6 27k 2 t CA3080 _Vcc 3 5 ICS Figure 19. A swept frequency, volt- R8 56k age controlled dual filter. This circuit includes a band pass and a 10k low pass filter, both of which can be fin simultaneously swept over the O range 7 Hz to 7 kHz, approximately. CONTROL The Q can be varied by means of the 10k'0 Control' potentiometer. ETI July 1983 - 123 OP-AffiP COOKBOOK SELECTED DATA ON THE 3080 Resistance TransconduCtance Input and Output Capacitance Output 7 104 106 nuu.:ñiu::;;;=_:: uu, 6 IIIIIq11IIIII Itlll -;;;,--T- 111P' \1I IIIIIIh11111111111 ____-11111 l IIIIII ,o, Illli=AI4 Pe IllIIIIII ,oJ -.-...::::. 6 CIN-va1ñlll ===...: ---I;;;;=-;__:®;; ==-o:: 1111 111111§ FP--- ;IL 66°C 1li ./lw Vúáii Linu1: II tl3i.ii.i --111111I111111 COUT II IIIII tl:ll 111 N1111111 11111 _$ ñln 10111 11.'/.//unu 4 _IIIINAIIII 11111III 103 IIIINI .26°c Ila.»I IHIIII , = 3 MI =c:: =3 i =` 111111 I llll aal a\°I III aal. a 111111 NII11I' /.I ::::.:°o Lalalllui Iff ,II:111111111 11 SRI III . 1111111 2 IIIIIIII 11111111_ IIIII__ llllll®IIIIII 11111I 10 102 11H11nIHÍÍ1-:* at VS= 16V II OCi::úi) .--r iil:la- 1_-'::1 go:::: TA +26°C ME111 II' % 1111111 .MIL .IIIIII I I ,]IIIG I I I Ililltl 10 NW .04E11II III too o 0.1 1.0 10 100 1000 1 1.0 10 00 1000 o1 1.0 10 loo 1000 9 IABC-AMPLIFIER BIAS CURRENT (MA) IABC-AMPLIFIER BIAS CURRENT (NA) IABC-AMPLIFIER BIAS CURRENT (M.A) Peak Output Voltage and Common Mode Range Input Resistance Amplifier Supply Current IS 104 =_^§=SE:..===E:: If1n11 102 ' 1 111ll vOUT 14 v3 'IS V C M11 .a11ñY11ii11.a1111 111111111 <1 14 11tI1ilii7r1 .1 1o1 me lit 11111111111111111111111 III1nu1I1 -_µ:,.;__ : ;1::;:. I C SI/11,1 'i:= r=i::.1111rMII i::: ::m::::::ii+[ 1IIIIIIII111IIPIhl1111IIII111NII11 11111i:: 6 l/11111 ÚÍItiWItl1 W11 VS 16 V 1.0 IIII 11111111 N111111111 m11N ,I;9 f11NN1f11IÍIN11 IIII t :itl111N R10A0 - s TA +26°C plll 1111111111111 11111 rY11:Iaa1.M111111Í:. II .e1111 :.:T:O::.::::C:.:::. IIHIIII I IIIIMnuuIZNI1111J 0.1 (III IH Ifll gII}I7f`IIIpHII \HIN111 10 1111111111II VPNR I 1111IIIIN S-' --_::: ?-5- -14 ::r .';:i: II IrLw 11111111111111 imam II S. IN 1111.11111 .mime1111t11.11.1 1111 11N11 1111ININ111NIHH11NNII2INIIIII nllHllnl=ní!!11 Ilih.' 0.01 n 0.1 1.0 10 100 1000 01 10 10 100 1000 1.0 10 100 1000 BIAS CURRENT (rA) IABC-AMPLIFIER BIAS CURRENT (NA) IABC-AMPLIFIER BIAS CURRENT (MAL IABC-AMPLIFIER General description Features Differential Input Voltage +/-5 V Amplifier Bias Current (IABc) 2 mA The 3080 is a programmable transoonductance block intended Slew rate (unity gain compensated): 50 V/us DC Input Voltage +Ns to -Vs to fulfil a wide variety of variable gain applications. The 3080 Fully adjustable gain: 0 to gm RL limit Output Short Circuit Duration Indefinite has differential inputs and high impedance push-pull outputs. Extended gm linearity The device has high Input impedance and its transconduc- Flexible supply voltage range: +/-2 V to +/-18 V bias current tance (gm) is directly proportional to the amplifier Adjustable power consumption (IABC). High slew rate together with programmable gain make the Absolute maximum ratings 3080 an ideal choice for variable gain applications such as Supply Voltage 3080 +/-18 V Internal circuit of the 3080 sample and hold, multiplexing, filtering, and multiplying. Power Dissipation 250 mW -(1+V 1). 7 Electrical characteristics, 3080 (Note D3 4 Parameter Conditions Min. Typ. Max. Units Forward Transuntuctance (gm) 6700 9600 13000 umho Over Specified Temp. Range 5400 umho T7 RL = 0. IABC 5uA 5 uA Peak Output Current = OUTPUT RL-0 350 500 650 uA 300 uA RL -0 6 Over Specified Temp.Range (-) INPUT Peak Output Voltage TB RL = IABC 500uA +12 +14.2 V Positive ,5uA 2 V Negative RL = , 5uA IABC 500uA -12 -14.4 Amplifier Supply Current 1.1 mA Common Mode Rejection Rabo 80 110 dB V (+1 INPUT Common Mode Range +/-12 +/-14 Input Resistance 10 26 3 Open Loop Bandwidth 2 MHz Slew Rate Unity Gain Compensated 50 V/us T1 D4 'AMP D1 BIAS INPUT Note 1: These specifications apply for VS = +/-15 V and TA = 25°C, amplifier bias current NBC) = 500uÁ, 5 -0-V unless otherwise specified. 4 124 - July 1983 ETI Voltage controlled filter A standard dual integrator filter can be Metal Can Package constructed using a few CA3080s. By NC Dual-In -Line Package varying IABC, the resonant frequency NC can be swept over a 1000 to 1 range. IC1 1 NC and IC3 are two current-controlled in- 8 NC 2 7 tegrators. IC2 and IC4 are voltage (-) INPUT v+ INPUT OUTPUT - followers which serve. to buffer the high 3 6 impedance outputs of the integrators. A (+) INPUT OUTPUT third CA3080 (C5) is used to control the 4 5 AMPLIFIER (+) INPUT AMPLIFIER V- - BIAS INPUT Q factor of the filter. Q factors as high as BIAS INPUT 50 can be obtained. The V- resonant fre- TOP VIEW TOP VIEW quency of the filter is linearly propor- tional to IABC and hence this unit is very useful in electronic music PIN CONNECTIONS FOR THE 3080 IC production. There are two outputs, a low pass and a band pass response. Minimum fre- quency is around 7 Hz to 10 Hz,'upper LP OUTPUT frequency is around 7 kHz or so. BP Changing C2 and C3 will alter the OUTPUT upper and lower frequency limits. 7kHz Figure 7Hz 20. Illustrating the operation of the filters in (MINIMUM (MAXIMUMI the Figure 19 circuit. Ir FREOUENCY CONTROL RANGE NOT 20 PROJECTS NOT 25 PROJECTS NOT EVEN 35 PROJECTS .. , BUT .. . 50 PROJECTS! ...WOW! The great, N. ti . grand, gi-normous r. b HOBBY ELECTRONICS PROJECT BOOK `""Nr. , . is here at last! This book must have just about something for everyone. .: Something for the dabbler or dab hand, for newcomer or old timer. Contemplate it - 50 projects in six categories: Radio & Communications, Music & Audio, ( ,: Games and Hobbies, Test Gear, Measurement, Miscellaneous, PLUS: Construc- -¡ tion Techniques and a Reference section! Amazing - 50 projects and 15 articles, a veritable hobbyist's 'bible'. The articles cover project construction, the art of soldering, making printed circuits, capacitors, how to read capacitor r codes, diodes, transistors, inductors, transformers, reading circuit diagrams, - component numbering and where to buy components. Printed circuit board patterns are given and all the component pinouts you need to know about. THAT'S RIGHT! $4.95 This must be the best value ever.in an electronics book. Rush out now and get your copy before they all go - which they're bound tol On sale at newsagents and selected electronic suppliers. Or, you can obtain a copy by mail order from ETI Book Sales, Federal Publishing, 140 Joynton Ave, Waterloo NSW 2017. by sending $4.95 plus $1.10 post and handling. ETI July 1983 - 125 Schmitt Triggers BUILDING BLOCKS RB Basic Op -amp Building Blocks VIN VOUT Voltage followerlbuffer Non -inverting; input hysterysis levels = t(RAIRB)) x VouT Input must have a DC path to ground VIN VOUT Inverter Voltage gain = -1 RB input impedance = R Inverting; input hysterysis levels = t(RAI(RA+RB)) x Vow. Note that VouT depends on the supply voltage and the Non -inverting amplifier Input must have a DC path individual op -amp to ground 'ABC Voltage gain = (RA+RB)IRP Inverter/non-inverter amplifier VIN Voltage gain = +1 with VOUT SW1 open VIN Voltage gain = -1 with SW1 closed R tLSW1 Transconductance type; input hysterysis levels = t VouT' VOUT = R : IABC R can be replaced by two 1N4148 diodes back-to-back When trying to convert a slowly changing voltage into a step function with a Inverting Amplifier well-defined leading edge a good Schmitt trigger is invaluable. This is a simple Voltage gain = - RBIRA but effective trigger capable of good results in the audio passband. Once again, The RB Input impedance = RA for higher frequency use substitute a faster op -amp for the 741. Schmitt trigger works by using positive feedback to establish a 'deadband', a range of The power supply and compensation are omitted from these diagrams. If input voltages within which the output state will not change. The input voltage internally compensated devices are used no additional compensation is must exceed the higher limit in order to force the output high. Similarly, the Input necessary, 1.e: 741, TL071, TL072, TL074, etc. If additional compensation is voltage must be taken below the lower limit to force the output low. The extent of required consult the data sheets on the particular device used. this deadband is given in the equations. VREF Antilog (Exponential) Converter 10v Log Converter IMO VOUT = I x 100k I for 1 V increase of VIN The current doubles every 10oA 100k When VIN = 0 V, I = 10 uA VIN VOUT 100k 56k 1k0 FOR LOW TEMPERATURE DRIFT USE A 081 RESISTOR 1V o VOUT LOGARITHMIC RESPONSE Vow changes by 1 V for every octave change of the IIN current o VOUT 'The matched transistors can be two BC2121. in thermal contact, or EXPONENTIAL a dual RESPONSE transistor (1M394), or pat of an array (CA3046) 126 - July 1983 ETI AUDIO OP-AffiP COOKBOOK Rumble Filter Low Impedance Source Preamp 39k 5k6 39k 47k Very low input noise Input noise = 4 nV Hz Equivalent input noise voltage = 0.56 uVlim, (20 kHz bandwidth) Input impedance = 1k0 (suitable for m crophone) 00k 3k9 oy 4u7 16V TANTALUM 10u INPUT 1k1 0'' OUTPUT 4th ORDER HIGH PASS 47k RESPONSE OV 24dB Roll -off slope = 24dBloctave ( Overall voltage gain = s 2.6 (8.3 dB) Op -amps are 741's or RC4558 Variable gain; z 3.9 to z 100 (12 dB 40 to dB) FREQUENCY 7k5 Fc C R 28d8 25 Hz 100n 62k 31d8 50 Hz 100n 30k 100 Hz 100n 15k 200 Hz 100n 7k5 34d8 (5% tolerance) 3748 Simple Mixer INPUT MAX GAIN INPUT SOURCE IMPEDANCE 413 1 +6 dB 10k line level 2 +20 dB 5 4u7 to 10k line level 16V .15V 120R 3 +46 dB 1k0 low impedance TANTALUM 2 microphone 7 +... l0u 4 +6 dB 1MO high impedance 'PUT lkOr 5534 4 OUTPUT input 3 INPUT 1 47k -15V 10k 10On o OV 10k log 47k Switched gain; 3 dB steps The NE5534N is a very low -noise op -amp specifically intended for audio appli- cations. The device boasts one of the lowest noise figures of all op -amps INPUT 2 100k with (O--1 combined good slew rate and large signal bandwidth figures. í100n The lowest -noise devices have the designation NE5534AN. Suitable supply decoupling is essential if best results are to be obtained. l 10k log OUTPUT 4u7 Slew limiter TANTALUM INPUT 3 CA3080 VIN DC 5 r SIGNAL I L981 5 2t1N4148 O IABC 47k = I 4n7 Slewrate ABC volts per IO.SmA MAXI INPUT 4 c second v,c H 150k 10k log SLOW INPUT 10k log 1N4I48 This simple mixer has been provided with four different types of input circuit. Any combination of these could however be used. Once the 741 OUTPUT f . n again, limits the high frequency response and slew rate capabilities. To improve performance substi- tute the 741 for a taster device such as an NE5534N or TL071, etc. ETI July 1983 - 127 FILTERS 10k 10k 4n7 566 4 8k02 10k 100k LP OUTPUT -3dB LOWP ASS POINT MVW 10k 33k HP 0 STATE VARIABLE 20 ~ OUTPUT 4th ORDER RESPONSE BUTTERWORTH 40 RESPONSE Elliptic lowpass (de) (-24d8/OCT) 4th Order frequency is 4 kHz. To change cutoff frequency, scale 60 FINAL ROLLOFF Cutoff .1,M C off) (-12dB/OCT) capacitor (four 80 111~1111ff' 4k 8k 16k FREQUENCY 39k 47k Lowpass Active Filters 39k 5k6 Inputs must have a DC path to ground OUTPUT R 1 ` 2 R INPUT 2 pole roll -off = -12 dBloctave 4 pole roll -off = -24 dBloctave c R C Fc 4 pole Butterworth 107k 15n 100 Hz 39k 22k 10k7 15n 1 kHz 10k7 1n5 10 kHz OUTPUT INPUT RESPONSE 2 POLE 4 POLE FC 2 pole Butterworth FREQUENCY M Vs State Variable Filter 10k 10k NOTCH RESPONSE 10k INPUT AL.SANDPASS FREQUENCY F = 1 Hz LOWPASS - ` RC o 27c. HIGH PASS LOWPASS +12dB/OCT -12dB/OCT RESPONSE BANDPASS (30 -1)10k r HIG HP ASS 10k FOUR FC FREQUENCY o OUTPUTS Gain = Q Q and Fc are independently variable. Fc may be tuned with a double 10k 10k gang pot (for R). Q factors as high as 100 may be obtained. All responses track with frequency. NOTCH R C Fc o 107k 1Sn 100 Hz 10k7 15n 1 kHz 10k7 1n5 10kHz 128 - July 1983 ETI OP-AfflP 000KDOOK Active Notch Filter SO Hz Notch, Variable Q The two R's in parallel represent R12 The two C's in parallel represent 2C INPUT 680k 680k TL081 O For 50 Hz, R = 680k, C = 4n7 (a hum remover) OUTPUT 1k5 FEEDBACK 3406 { 11081 \+ 0 ADJUST ~i 47k F 1 -114n7 4n 7 ` 2nRC RESPONSE RESPONSE LOW O FC FREOUENCY 50Hz FC FREOUENCY This is a modified version of the basic Twin -Tee notch filter. The O can be A basic Twin -Tee notch. Rejection depends on component matching, so for best adjusted by controlling the amount of feedback with the 47k potentiometer. The results use high -stability components. rejection offered by the circuit is determined by the matching of the passive components, but even with ordinary components a figure of 30 dB to 40 dB should be obtained. Bandpass Active Filter Fc = 112,LCJRA+RB Q = 112 RARBI Fc = 1kHz, C = 15n Gain = 2Q2 RB Q GAIN 10k6 10k6 0.5 x 0.5 21k2 5k3 1.0 x RESPONSE 2.0 42k4 2k65 2.0 x 8.0 84k8 1 k32 4.0 x 32.0 RB INPUT This is probably the most common bandpass filter. The circuit is really only useful for the relatively low O shown. For a higher O one of the more complex bandpass FREQUENCY circuits should be used, such as the state variable filter. 39k 47k Highpass Active Filters F = 1 Hz 39k 22k 2nRC 2 pole roll -off = + 12 dB/octave 4 pole roll -off = +24 dBloctave OUTPUT INPUT RESPONSE R C Fr 4 pole Butterworth 2 POLE 107k 15n 100 Hz 10k7 15n 1 kHz 10k7 1n5 10 2 kHz pole Butterworth FC FREQUENCY ETI July 1983 - 129 look oP-AmP 100k CCW CW 10k CCW CW 10k COOKBOOK 100k lin MAX FREQUENCY (100k 47k lin MUSICAL 27k CCW CW MAX O 10k 470k lin 22k Equaliser ./v" Parametric o O OUTPUT INPUT 470141lOk47o CONTROLS 47k . lin 2 CCW CW MAX O LIFT/I/IA4CUT 300H: 7K Hr MIN MAX CUT LIFT FREQUENCY O RESPONSE 10k On 4.9V (BATTERY) For Guitar 100u DISTORTION Fuzz Unit CONTROL 100n 47k 1M0 47k log TL081 47k f- log jack can VOLUME on via the jack socket (a stereo ,OUTPUT The battery can be switched -0 be used). 200Hz 800Hz 3.2kHz 12.8kHz 0--^/.4"/50Hz CUT OUTPUT I NPUT 100k -O 100k 100k 100k 100k Graphic T150n Equaliser Input must have a DC 680n 150n I 39n I 8n2 2n2 path to ground 10k Use 741's for op -amps 10k 10k S 10k 10k Cut and lift = 13 dB max Filter spacing = 2 octaves I 0 +12V + 47R 100u 9 3 2 MODE VCC LED Peak Program Meter 16V TO +6dBm t 4 11 R LO +3 INPUU- 200k 200k 2k2 5 2 SIG v 1000 IOOk . 100k 13 T 70n 3 1N4148 4 1N4148 REF OUT. 6 11N4148 15 741 457 -9 16 i^i REF ADJ -12 Inn 17 3k3 LM3915 15 (NATIONAL SEMICON- 18 LA// FULL WAVE PEAK DUCTOR) -18 VOLTAGE DETECTOR Leave pin 9 open circuit for dot operation 1 21 If an 1M3914 is used the display is linear, not logarithmic / `t ALL RED LEDS fa 130 - July 1983 ETI The National VP-5512A Pana Scope. VP- 5512A We increased the range to 100MHz, the channels to 4 and the trace to 8, but you'd never know it from the price. A Scope that does more and tells more Here, for the bottom liner, is a scope that really performs! You get your rr41 Sail"? 100MHz with an alternate sweep function in a compact package. You get a 4 -channel, 8 -trace format so that a large number of signals can be 111 e simultaneously observed with ease. And you not only watch 4 different a /_ .t/ kinds of waveforms at the same time but you also get measurements of > sic phase differences in signals and their timing. ,_ orc S Z#V Features galore in a unit you can trust And that's not all. Listen to these outstanding features: an Auto -Fix circuit 4 - for easy triggering, a National exclusive; bright, clear waveforms on an advanced domed -mesh CRT, a National speciality; 2mV/DIV sensitivity; 2 VP -5234A VP -5256A nSec/DIV maximum sweep rate; ±2% time axis accuracy; a TV sync DC -40M Hz. DC -60M Hz. separation circuit for video signals; variable hold -off function for trigger 15,000 hours MTBF. 15,000 hours MTBF. Triggering waveform Alternate sweep stabilization; alternate triggering; drift compensation; and more. on CH 3. function. Ideal for lab, line or field service Auto -Fix and Hold -Off Auto -Fix and Hold -Off You also get that world renowned National reliability in every National control. control. oscilloscope. for reduced which Delayed sweep. Alternate triggering We have, example, parts by one -quarter, Alternate triggering function. means, of course, less wiring and less failures. We have installed glass function. Triggering waveform epoxy circuit boards which have far greater resistance to shock and heat. TV sync separation on CH 3. circuit. -mesh with There is also a 15,000 -hour MTBF (Mean Time Between Failures) rate, Domed CRT illuminated internal certainly one of the finest in the industry. graticules. So the next time you're looking for a reliable scope that's been fully upgraded in range, channels and trace-everything, in fact, except price-remember the VP -5512A Pana Scope. From National. PRICE: $2,200 - )& Sales Tax if applicable) SCIENTIFIC DEVICES AUSTRALIA PTY. LTD. 2 JACKS ROAD, Sill OAKLEIGH 3167. PHONE: 579 3622 )7 31 HALSEY ROAD. ELIZABETH EAST, S.A. 5112. PHONE: 255 6575 i 35.37 HUME ST., CROWS NEST., N.S.W. 2065 PHONE: 43-5015 National Why some CMOS circuits don't work as you expect Stephen Dolding A 4093 is a 4093, right? Well ... yes, and no. There are quite a few pitfalls in the CMOS 'jungle' and it's handy to know about them before venturing forth. CMOS '4000' SERIES integrated circuits are You have selected stable, close tolerance With the same type from another manu- manufactured by at least six major manu- components and calculated the frequency ac- facturer, Vt+ could be 2.7 V and Vt_ could be facturers and the 74C series by at least two cording to the formula: 2.2 V, in which case recalculation gives a 249 Hz! major manufacturers, but it must not be as- 1 frequency of rout = sumed that a 4XXX from one manufacturer These figures are based on typical values Vt+ level. Extremes of high and low is interchangeable with a 4XXX device from CRloge Vcc- Vt_ of trigger another manufacturer. This article explains trigger levels could give frequencies ranging some of these differences. C\ I\ Vt- / from 27.5 Hz to 961 Hz with the same values of C = 100 nF and R = 10k. This gives a fre- Schmitt gate oscillator where C = capacitor value in uF quency range of almost 35:1 if the whole R = resistor value in kilohms spectrum of possibilities is considered. the oscillator What could be simpler than = frequency out in kHz Now it will be clear why the circuit may shown in Figures l(a) and 1(b)? rout circuits Vcc = supply voltage oscillate at a frequency which is consider- so few components that you would There are Vt.,. = upper trigger level of Schmitt ably different from what was expected or in- work first time. expect these circuits to trigger tended by the designer who only consulted 1/6 OF 74C14 VI_ = lower trigger level of Schmitt one manufacturer's databook! 74C914 trigger MC 14584 40106 OR is, values The monostable 40014 Now, the question "what are the of Vt.+ and Vt'?'. We need to refer to the Now let us look at another CMOS circuit manufacturer's data sheet for an answer. used by hobbyist the 4528 dual foul often the - But which manufacturer? There are at least monostable, shown in Figure 2. J u L six different manufacturers to choose from and each one gives a different range of possi- ble values for Vt., and Vt.. Figure 1a. Different manufacturers ICs will produce Considering the 4093 IC (Figure 1( b) ); if different results. all the databooks are consulted it is found that for Vcc = +5 V the highest typical value of Vt+ = 3.6 V (extreme = 4.3 V). The lowest typical value of Vt+ = 2.7 V (extreme = 1.7 V). The highest typical value of V. = 2.2 V (extreme = 3.3 V). The lowest typical value ofVt. = 1.4 V(ex treme = 0.7 V. Now if V1 . = 3.6 V, Vt_ = 1.4 V. Figure lb. Such a simple circuit but the value of foul V. = /-5 V, C = 100 nF and R = 10k, can vary from 52.9 Hz to 249 Hz, depending on the then from the formula above Figure 2. The 4528 dual monostable can have varia- brand of 4093 used. _ lout 52.9 Hz. tions in its performance of up to + 50°°. 132 - July 1983 ETI Lab Notes Here again, different 4017 manufacturers give The problem of logical differences between different formulae for the monostable time one manufacturer's device and another man- constant. A typical formula (for +5 V sup- ply) is ufacturers device ( with supposedly the same type number) applies also to the 4585 four - t = 0.37CR bit comparator and even to the ubiquitous However, it could vary from t = 0.32CR to 555 and 556 timers. There may be other ex- t = 0.42CR typical, with variations up to amples too. The problem fortunately does not loon ±50v/ . occur with the range of quad gates. The pulse width depends very much on the Figure 3. This circuit will only work correctly with supply voltage. Some manufacturers' 4528s particular brands of 4017 decade counter/dividers. The moral The wrong choice can result in false counting. give increasing pulse width with increasing The above -mentioned examples were all en- supply voltage, others give a reverse effect. countered during the design of one piece of The formula given above depends on the Will the circuit in Figure 3 always work industrial equipment which made use of value of C being greater than 10n. For smal- correctly? No, only with a Motorola 14017 or these common CMOS parts. ler values of capacitance the manufacturers' an RCA 4017, because these have an inter- You may well ask -If design engineers. data sheets need to be consulted. nal Schmitt trigger on the clock input. Other who have ready access to all the data books. It should also be noted that some manu- manufacturers' 4017s do not, so false count- can run into such problems, what about the facturers require pins 1 and 15 to be ing may result. unsuspecting hobbyist, who has no data:'" grounded externally for correct operation. To The moral of this article is that "fore- overcome the variations in timing a formula, BCD warned is forearmed It is hoped that this CMOS 4538 integrated circuit can be used in decoder article may at least prevent some construc- place of the 4528. The 4538 is pin compatible Another fairly common integrated circuit tion projects from being abandoned because with the 4528 IC and the formula is: likely to give problems is the 4028 BCD -to - they do not appear to work correctly at first t = CR 10 -line decoder. We now come to see that sight. Designers who publish projects should with variations of only ±5%. actual logical differences can occur between check that there are at least two manu- In all timing circuits using CMOS ICs it is one manufacturers 4XXX and another facturers ICs which will work in the circuit wise to make provision for trimming the manufacturer's 4XXX. as intended and, if necessary. spell out the value of the timing resistor to allow for With the 4028, some manufacturers names of suitable manufacturers in the parts adjustment. (Motorola and RCA do not decode the six list. Best of all. only design circuits that will 'illegal binary codes 1010 to 1111 ti.e: 10- work with all manufacturers devices of the The 151, while other manufacturers (including same basic type number (though this may counter/divider National, Fairchild and Philips) decode not always he possible). Next we come to a well-known decade these outputs as ifthe input was 8 (1000i or 9 If problems occur, a l l that may be required counter/divider IC - the 4017. í1001t. is to try an IC from a different manufacturer. BILLCO ELECTRONICS UNDER NEW MANAGEMENT Shop 2, 31 Pultney Street, Dandenong, Victoria, 3175. Telephone: (03) 791 8655 PRODUCTS AT COMPETITIVE ELUSTROf ICS Breadboard sytem ETI 660 COMPUTER KIT PRICES INCLUDE: (PCB & COMPONENTS) ° * Comprehensive range of $100.00 IZUMIYA IC INC. Printed Circuit Aids transistors, resistors and TRANSFORMER $7.50 capacitors * Kits * Meters CASES (KEYBOARD & PCB) and instruments * LED and RRLEC Transformers and accessories $27.00 LCD Displays * Plugs, sockets, TOTAL PRICE cables * Tools and hardware OK MACHINE e- Wire wrap tools * Books and magazines Ik.' TOOL CORPORATION & equipment PACK & POST $10.00 ETI COMPUTERS & * Instrument cases * PCBs 111 TOVO Mini lathes and drills for ETI, EA and TE Projects COMPUTING HOURS OF TRADING (ETI 660 PROJECTS MAIL ORDERS WELCOME Mon - Thurs 9.00am - 5.30pm COVERED) $10.00 SCHOOLS AND TRADE Friday 9.00am - 9.00pm RECOMMENDED FOR 660 SUPPLIED Saturday 9.00am - 12 noon CONSTRUCTION $4.95 ETI July 1983 - 133 IDEAS FOR EXPERIMENTERS are intended primarily as a source of ideas. As far as reasonably possible all material has been These pages and checked for feasibility, component availability etc, but the circuits have not necessarily been built tested in our laboratory. Because of the nature of the information in this section we cannot enter into any correspondence about any of the circuits, nor can we produce constructional details. Monster flasher Andrew Stewart of Gumdale +12 V Queensland has a little monster which sits on the dashboard of his car and flashes its eyes (LEDs) 2M2 indicator and brake with the 1M lights. Now many of his friends monster. want a 'flashing eyed' 4u7 He sent us a copy of his most ad- 10k vanced unit. i in a car 71 16 16 As the ignition system 7 6 F51 n= o is often noisy Dl is needed to iso- late the 470u capacitor from the 100n ICI IC2 12 V supply. 555 ICI 555 gives a time delay of 555 imam 100n over a minute and when it finishes counting it sends a pulse 121 3 to IC2 555. The output of IC2 2 U 25u then goes high for approxi- ASTABLE mately 4-5 seconds. This, in T33u ASTABLE MONOSTABLE turn, causes 1C3 to oscillate and 1N914 the monster's eyes blink. 0V 100u The 1 k resistor brings the duty cycle close to 509 . The 100 uF capacitor on the output of IC3 RIGHT INDICATOR if 470u O makes the eyes look as they are =D7 I INPUT fading in and out. 1 N 40011 LEFT I for mount- The monster used O-L- INDICATOR ._941 in was a cheap 12 V INPUT 220R 220R ing the LEDs INPUT plastic lizard. The ICs can be BRAKE mounted on Vero board and INPUT placed inside a matchbox up un- = 0 der the dashboard. Valve distortion NC 1N4007 unit want a valve 1.S00k If you really distor- TONE tion unit, Jeff Parkes of 220k look 1000u/50 V - Collingwood Victoria has 22n one. 47n .. TO 15 V TAP designed INPUT 2 I built this effect pedal in an SW1a OUTPUT OUTPUT TO aluminium box with dimensions GUITAR AMP ,VOLUME SW1b 13U mm x 75 mm x 55 mm. It is 1M 165 500k of INPUT almost hum and noise free and VOLUME 47n sounds great with a gutsy guitar 470k such as the 'Les Paul' type. 1 have left it running for sev- 1512AX7 1,,12AX7 - 15V eral days and the performance has remained constant. The 240 Vac I -6.3 V TO PIN 9 transformer is a 2 155 and SW is PINS 3,6,4,5 AND an audio quality DPDT foot - SOCKET SHIELD TO EARTH 0V switch. 134 - July 1983 ETI chotiSTurtle The HEBOT 11 turtle is not just fun device, is it a positive aid to education, it takes programming out into real sional world instead of the flat two the 3 dimen- dimensional world of the VDU. When connected to the I/O ports of your given a DC supply of 9-15V the turtle runs computer and around under computer control moving forwards, backwards, right left independent control of each it has and with wheel, blinking eyes, will bleep with a presses down choke of two tones and when ordered by the computer, a pen to chart its progress and provide hard copy turtle of the results of the program. When set free to run around the discovers its environent, When the turtles shell bumps into for an unmovable obstacle touch sensors send back data to the computer it to Calculate evasive or exploratory action. If the computer has no I/O ports it doubtless has an expansion bus and with the turtle can be controlled and listened to using this bus together the universal computer interface board. This board enables the device. turtle to be treated as a memory mapped I/O COMPLETE "HEBOT II" KIT INCLUDING ALL 11 HARDWARE, DOME, Brand new WHEELS etc. Cat. XR1020 UNIVERSAL INTERFACE CARD KIT Cat XR1022 $399 inc tax $3950 Ji 16 BIT COLOUR FM Transmitter Module NFib We have been working on this one for years!, Basically we wanted something akin to the $6.50 kit "wireless microphone" transmitter but with greater COMPUTER KIT signal strength and far, far greater frequency stability. N` WE NOW HAVE IT/ Basically (potted! the unit measures a small 90 x 22 x 15mm and has connections for power, antenna and input An AC signal between 20 and 15kHe will modulate the transmitter. The signal can be coded single or multiple frequency tone Invests etc. FEATURES SPECIFICATIONS Ultra low noise output (-60,I8 or better Frequency - 88 108MHz adjustable attainable with a suitable tuner) Useable range 50 metres Excellent frequency stability Supply - 6 to 9V at 20nA Not krt a - ready for immediate use Input sensitivity - adustable maximum Connections - 3tnV required Pre emphasis - 5I a'second standard (al Power or supply battery Dimensions 90 x 22 x 15mm lb) Antenna - latvprox I (c) Audio input Full instructions supplied Suits any application where a stable low noise FM link is required $495 Cat DT5450 . t- gsnIMIM Cat AZ5010 At last a high quality 16 BIT micro 'mini?) Computer Kit is available in Australia. This extremely powerful machine is based on the Texas TMS9995 processor. WIRELESS We simply do not have room to list all of the features of this machine. A few High speed 24K byte extended basic interpreter Auto line numbering facility 48 bit floating point gives 11 digit accuracy Full renumber command High resolution (256 a 1921 Colour graphics Simple but powerful line editor Screen memory does not use up user memory Buffered I/O allows you to continue executing GUITAR Space the program while still printing 16 colours available on the screen together in Flexible CALL statement allows linkage to Graphic mode machine code routines with up to 12 parameters Fast line drawing and point plotting basic Basin programs may contain spaces between key commands words to make programs readable without using High speed colour shape manipulation from basic LiNK TOM memory :go We have marte Full textual error messages Over 34K bytes available for basic programs even a SCOOP PURCHASE of the MUSOL INK FM Wireless system The String and Array sire limited only by memory when ex tended basic includes IF -THEN ELSE MUSOLINK enables a guitarist Uor example! to operate live vinMont trailing cables This low cost system sire Supports up to 16 output devices: Screen and transmits a rock steady signal to any commercial FM tuner. The signal is restricted to the largely low Real time clock included in basic cassette included as standard unused end of the 88 108MHz FM band Many MUSOL INKS can be used in, say, 1MHz of FM band Interval timing with lOmS resolution via TIC Supports bit manipulation of variables from width as they have excellent frequency stability. function basic Normally this unit sells for 5149 but we have balk purchased and now pass on great savings, Named load and save of bin c or machine code Error trapping to a basic routine included programs Basic supports Hexadecimal numbers run Auto available for any program Includes UHF modulator, tape interface and a Powerful machine core monitor power supply with extra capacity for extra LIMITED STOCK Assembler and Disassembler included as standard interlaces NOW $99 NEW LOW PRICE If you want to know more about this machine send SAE for more details. (Disc drives NOT included) BACK AGAIN! ULTRA VIOLET LAMPS $3.95 Ultra violet lamps - New Flood' Powerful "Mini design 100 watt rating Stan lard tom St i banned' COMPLETE KIT Low Cost fitting Cat. 512680 INCLUDING CMOS SENSATION METALWORK RS-232 Huge Super scoop buy of the scarce 4026ÁE device means that you save, y!. L For Cat KJ3660 years the 4026 decade counter 7 segment decoder driver has been one of the most difficult to INTERFACE obtain. parts Jayear has made a scoop purchase of this device in the "AE" form loin are not certain that ,t was ever Cat KJ6631 made as a "B" suffix device) It has been largely replaced by rye 4426 Iwfuch is not an exact equi 'relent!. The 4426 for Value sells 52 20 and so to does the 4026 when ,t is available but for JULY only the 4026 $1299 $ price has been slashed Cat. ZC4026 Prices INCLUDES sales tax 49.50 1 9 $1.50 each 10 - 99 Sl 25 each 100- ONLY 99 cents each SEE JAYCARS OTHER ADS FOR ADDRESS DETAILS ETI July 1983 - 135 INTRIGUING JAYCAR - SEE THE OTHER JAYCAR ADS IN THIS MAGAZINE FOR OUR STORE ADDRESSES AND PHONE NUMBERS.... t,,,,codemaster..,4gie $995 We now stock a COMPLETE range ofhigh efficiency `1 Silicon Solar Cells. All cells give 0.45V under rated -`- load and they can be stacked in series or in parallel ' for higher current Cat No Description 1-9 10+ ZM9002 Rect. 10x2Omm 45mA $2.45 $1.95 DISCO-STROBE LIGHT ZM9003 3" diameter 1 amp $26.50 $2250 11044 ill/Y ZM9004 3" diameter x 30D segment 78mA 53,25 $2,95 `` A few left from our last shipment We have received our FINAL SHIP- ZM9005 4" diameter x ''4 segment 450mA $12.45 $11.95 + MENT of lowcost strobes. Unfortunately due to cost increases we have had to increase the price slightly. You must WAS agree that the strobes still represent COMPUTER $12.50 outstanding value for money. STILL TRANSFORMER almost HALF our competitors pricel Many of you know the clever parlour Remember these units are guaranteed game uses coloured stretch for 3 months. BARGAIN that tokens to the brain to work out a hidden code in a Quantities limited to 2 per Customer Cat XM7005 minimum number of moves. s245o The people that came up with the game 95 used a descriptive name which no-one else can use. It Is a popular game and is ONLY $1 SAVE $5.00 well known under this name. Our game Cat MM2020 '' WAS $29.50 is similar to this game but - naturally - its electronic!! And, what's more, you We have secured a quantity of a power transformer can play against the machine alone. at a never -to -be -repeated price. This unit is ideal as Each XM7015 Codemaster measures LCD the basis of an S100 power supply, but can be 140(I)x85(w)x25(d) looks similar to a GIiIGIPE eaGr used for many other computer or general power pocket calculator and runs off a standard supplies. 9V cell. Provision is made for a mains ,CI) m2 SPECS: Primary 240V AC - Secondary 1: 15VAC adaptor as well. cc 2 amp - Secondary 2: 15VAC 2 amp - Secondary The Codemaster once sold for $29.50 a°r;,l-I 3: 8V AC 8 amp. but Jaycar has made a huge scoop purchase. You save a fortune) oO ,oe /_II _I _I _I N A typical DC supply could be ±15V DC @ 1.5A & 5V DC @ 8 A or ±12V DC @ 2A & 5V DC @ Grab one now for only S}2.5811 STi 2 8A This transformer would normally sell for (For a further clue to the origin of around $50 - Brand new stock. this game read this page carefully) We have done it again! Once again Jaycar has secured a quantity of valuable LCD displays. Instant Data on the Most Popular Once again we are passing them on to you at MICRO CHARTS Computer and Mlcroproc.ssor Pans 2SC2545 FuIlF JecndeJ data no need 10 nun,s prices that will make our competition green un.eramp e 2SC2545. The low noise with envy) transistor for pre -amps) Basically we have a 5 digit x 18mm high (See N.». c..J.t card maslc lasb a e.Lme EA April 1983) (that's BIG) LCD display. But there Is a snag, NOW Pertrrl toi prugrammeg arW nng nee, led s,n.. Jaycar has them) and here Is where you save. Normally this And load. cnmprenenA.e Only $1.95 display would sell for around $20 - if It had ONLY ; cti.a ^nd edn<.se Iml. .el m; Cat ZT2400 the connecting pins bonded to the glass sub- r SCnPsncCO OW Pane g I umP ru ualuór I F strate. But this display just has the metal- $9.95 n,agrami Ong o .F and m m mrr lization on the glass substrate. Too hard to Cat BM8500 Z80CPU SAVE I ,= Cat BM8501 8080A/8085A connect you say? No, not at Milli Col BM8502 6502(65XX) We have discovered that a humble Molex pin $3.00!! is JUST PERFECT as a connectorl You slip the Molex pin on to the edge and superglue Are the antennas on it in place. You then have a permament "rabbit ear" the back of your portable ONLY connection, a great LCD display and have TV broken? You know those ones that are telescopic and saved a fortune to boot) (Instructions for have ball -swivel joints. $7.95 fitting the Molex pins as well as FULL DATA Ne have genuine 'HMV' factory spares that will fit other TV's WHAT'S and connection diagrams on the LCD are Apparently they are almost industry -standard components. supplied). UP Each unit comes with a short length of lug -terminated 300 And what do you pay for this LCD display? ONLY S2.95 each or $2.50 each 10 up. ohm ribbon. DOC? Staggering value. Cat ZM9015 We have a small job lot available at only $7.95 each. Pack of 50 Molex pins (only 42 required) ONLY 220 SETS AVAILABLE. Cat P16540 Only $1.00 :at AA2005 $7.95 136 - July 1983 ETI IDEA OF THE MONTH *IDEA OF THE MONTH* Simple holder for leads, probes etc TO +VE VIA DASHBOARD 12 V TO CHASSIS VIA you want LIGHT DIMMER CONTROL 1 BUZZER DOOR SWITCH If to have a tide elec- tronic workshop this low cost lead holder should help. Parking light reminder H.F. Nissink of Launceston Tasmania sent in the idea which Stephen Mann, Forrestfield WA makes it easy to store test leads, There are many different circuits It's very simple to operate. The BNC to BNC connectors and test around for devices to remind you buzzer will sound when the park- probes etc. to switch your parking lights off. ing lights are on and you open the Slotted cable is readily avail- However, this idea must surely car door. This warns you to turn able through electrical suppliers be one of the simplest and the the parking lights off.. at a fairly cheap rate. This cable cheapest. An added feature of'this ci rcu it ducting, cut to the required The buzzer requires only two is that if you need to have the length and bolted to the wall, connections to the vehicle; one to parking lights on and the door works well as a lead storage rack. a door courtesy light switch and open. you can silence the buzzer The slot size is ideal for elec- the other to the positive battery by operating the dashboard dim- tronic type leads. As well, the terminal via the dashboard light mer control. cable ducting may be cut along dimmer control. its length through the centre of the slots with the base of the U - shape bolted onto the wall as 261 transistor battery clip shown. Darryl Green of Elanora Qld. I then soldered wires on to the Matchbox cabinet for small is another enterprising experi- back of the plate, taking care not menter. to melt the plastic. Hey presto! components I was breadboarding a small One battery clip. circuit requiring an op amp and Chris Nixon of Bentley WA has together to form a miniature ±9 V rails and found that I only found a use for empty match- cabinet. On the opening end of had one 216 9 V battery clip. boxes. each matchbox write the values But I did have an old 216 A simple but effective method and abbreviated names of the battery and discovered that by of storage for smaller components components contained in the prising the metal case open I could e.g: resistors, ) capacitors, tran- 'drawers'. remove the top plate with the sistors etc. is to glue matchboxes clips mounted on it. PRISE OPEN 'IDEA OF THE MONTH' CONTEST COUPON RULES Cut out and send to: Scope/ETI 'Idea of the Month' This contest is open to all persons normally resident í\ with Contest, ETI Magazine,140 Joynton Ave, Waterloo Australia the exception of members of the staff of Scope Laboratories, Federal Publishing Company Proprietry Limited, NSW Scope Panavise 2017. ESN, The Litho Centre and/or associated companies. Multi -purpose Closing date for Issue is last "I agree to the above terms and grant Electronics each the day of the month. Entries received within seven that be Today International all rights to publish my idea In ETI Work Centre. days of date will accepted If postmarked prior to and including the date of the last day of Magazine or other publications produced by them. I declare the month. that the attached idea is my own original material, that it has not The winning previously been published and that Its publication does not entry will be judged by the Editor of ETI, whose violate any other copyright*". .r decision will be final. No correspondence can be entered into regarding the ' Breach of copyright is now a criminal offence. decision. Winner will be advised by telegram the same day the result is declared. The name of the winner, together with the winning Title of idea idea, will be Scope Laboratories, who manufacture and distribute soldering published In the next possible Issue of ETI. Contestants must irons and accessory tools, have offered to sponsor a contest enter their names and address where indicated on Signature with a prize to be given away every month for the best item each entry form. Photostats or clearly written submitted for publication in the 'Ideas for Experimenters' copies will be accepted but if sending copies you must cut out include column - one of the most consistently popular features in and with each entry the month and page number from Name ETI. Each month we will be giving away a Scope Panavise the bottom of the page of the contest. In other words you can In multiple Multi -purpose Work Centre, Model 376/300/312, comprising a send entries but you will need extra copies of the magazine Date self -centering head (376), standard base (300) and tray base so that you send an original page number with each mount (312), all worth about $901 Selections will be made at the entry. sole discretion of the editorial staff of ETI Magazine. Apart from This contest is invalid In states where local laws prohibit Address the prize, each winner will be paid $10 for the item published. enures. You must submit original ideas of circuits which have not Entrants must sign the declaration on the coupon that they previously been Postcode published. You may send as many entries as have read the above rules and agree to abide by their you wish. conditions. ETI July 1983 - 137 SOCK Winter Stocktake Specials MIC BOOM ...you reap the benefit. 52450 This 79cm boom lealures a 8 - Neal, counterweight that ,s NOW adiusubfe to allow posn,onmg of the m,c rophone. Cat C-1230 PCB's: Way below cost 51 750 WAS NOW 765A4 Twin 25 H 8302 $11.50 $3.50 76PC9 Musicolor Mk3 H 8318 $4.75 .75 CALC 78B7M2 Radar Burglar- Alarm H 8330 $1.50 .50 78EK3 Elect. Morse Keyer H 8340 $2.75 .50 FA-3600? able MIC FLOOR 79MD9 Metal Locator H 8366 $2.50 .50 Casio STAND 80LS12 Select alot H 8384 $3.50 $1.00 and 300mm thecact base with 80RM 12 Cylon Voice H 8387 .75 SNowl.0Check u e 36 Una $2.75 out steps- adjustable stand and standard 801F12 Minispot H 8389 $2.20 50 Check thread lot microphone tortorenhnooi screw 80F812 Guitar Fuzz Box H 8390 sT.60 .40 attachment Cat C 1220 A'sanidealcalcal l 81SWI Oscilloscope switch H 8392 $3.95 .95 an idealvancedhighschoand etc. Ask hrdiicians a WAS s45O0 811R4 4C Infra Red Control H 8395 $4.20 .90 for students. 81CC5 PC Birdies H 8396 $2.50 .50 1 NOW $29°° 81RC4 Infra Red Beam H 8397 $7.50 $2.00 our tax. Price p3105 o 81SP5 Sound Pressure H 8398 $2.50 .50 Cat 81SS4 Speed Sentry Meter H 8399 $2.20 .60 HORWOOD BOXES 81OR7 Electronic Synth. H 8404 $12.50 $2.50 WAS NOW H-241O102x76x25mm EA81SM7 Pavloys Bagatelle H 8411 $3.20 .90 :8,59% ONLY1 $625 $4.25 H-2420 102x76x76mm $7.65 55 65 EA82VC3 Voice Canceller H 8420 $2.50 .90 H-2450 203x102x153mm 520.50 515 so EA82VX4 Voice Operator H 8421 $3.20 .90 Extruded heavy gauge alum- ETI419 100W Preamp H 8554 $1.75 .35 Casio inium section with close -fit- ETI810 M/cycle TV Game H 8615 $3.85 .65 A(1Cf».502ogromm°bye ble. ... gull ting ends FET Amp H 8633 $9.95 .95 progre m steps ETI257 Uni Relay Driver H 8638 $2.95 .75 5 amazigng 33 ETI158 Low OHM Meter H 8641 $2.75 .65 emoryor An sub- 88memory retention.rete veis, uP to 52nd - ical cal- HURRY - LAST CHANCE! nempugs .the routinesro 11kYou re right BULK culator? 110 ONLY L BUY IN Gat Q-3 SIGN A AND SAYE! WAS ALDER SOLDERING 4bq- stA1 jC SOLDER s s8ylsrs SET AID Top quality corrosion free multicore (18g) 200 grams For the person working with PC boards solder. 1.25mm this is an essential aid. Kit contains: Cat. N-1619 guide fork tool, scriber, heatsink clip and ONLY $495 The Exclusive stainless steel bristle brush. Can also be NOW IN 0.71 mm (22g) 200 grams used for restringing dials! Cat. T-2610 Dick Smith Cat. N-1623 $495 AMAZING $550 ONLY STOCK SOLDERING The VALUE FAMOUS ADCOLA Dick Smith STATION Here's our brilliant temperature High Impedance 12 Watt Soldering AUSTRALIAN controlled solder station, offering Multimeter you the very best quality at an Iron unbelievably low price. Compare 10 MEG FET INPUT SEMICONDUCTOR our Solder Station to others. S30 FEATURES INCLUDE: For the professional who wants HANDBOOK the lowest circuit loading ... you Variable temperature control want Application data for the nine the highest input impedance Reliable iron for general from around 200 to over 500 The FET input service or pro- to five engineer ... and the multimeter gives duction area and ideal for the hobbyist. degrees Celsius. you a huge weekend professional. 10M input impedance High Impact plastic handle, complete with Large temperature meter on DC voltage, and a The book you've always needed, a highly res- Tnclad 3mm long life tip. Cat. T-1820 the pectable 1 M on AC 'one source' reference for the Fully approved by Energy voltage. Tips to suit Cat. T-1854 common devices often used It Authority Batteries, test leads& instructions $2.60 contains data on hundreds of supplied. Cat C1-1200 semi -conductor devices- descrete, Complete with lightweight irork WAS NOW 1595 linear, TTL, CMOS, etc the types holder, cleaning sponge and S of components used extensively users manual!! ,121 ONLY in Australia, particularly by the Australian Electronics magazines. ONLY Cat B-4200 s10 FAMOUS EVERY OHM NEEDS ONE! 111 i`I SHURE W¡ WOOPS! We forgot to put them in our Catalogue ' (slap wrists) but we . -1 vNJ a . DEFINITELY still stockeC:51," YES!!! -, SAVE Shute Cartridges. S . M7OB (Spherical) :ee Cat. C-5511 $ 22.50 ea M9IED (Elliptical) We now stock the :1,3g Cat. C-5515 $49sa ONLY Styli bsutt incredible new `!- N70B (Spherical) C-5032 $17.60 COMMODORE 64 N7OOE) (Elliptical) Cat C-5034$19.95 N0I(Elip&-al) Cat C-6 $21.95 Computer Cat. T-2000 $59 Call in today for a free test drive .. . DIC SMITH wiE of Bargain Quality Stainless Steel Tools Grab Ba Dick Wow! Up to $30 worthand Smith Prices! `PHONYPATCH'PA Resists rust, spring more. Mainly components from M- load return, in- end of runs In our kit depart- sulated, easy grasp hand grips. I l g. l e WAS $20 I.andline I r ment also includes things like As seen in the May Issue of Electronics Transistor Nipper 40 channel £29 Cat V-1607 Today. Get ready for Phone Patching when CB switches, Ideal for PCB work, long life, cutting various pcb's, rubber feet its made legal-this great little kit is ideal for etc Storage Cassette edge. Cat. T-3205 etc. Fantastic bits'n'pieces for connecting a four wire leg transmitter/receiver) the hobbyist's junk box. Unit Mini Flat Nose Plier system to a two wire (eg phone lines or Suit Y-1600 WIZZARD Great for those small nuts. intercoms, etc). You R-7101 could even set your LIMITED Cat Comes complete with fantastic Cat for 1-3325 transmitter up complete remote opera- demo-cassette. $ tion using VOX. STOCK $4" Mini Needle Nose Plier UNIQUE IN AUSTRALIA! Ideal for small components, and con- fined spaces. Cat. T-3570 Cat K-3054 HORN SPEAKER A miniature rugged weatherproof Mini Long Nose Plier horn with an impedance of 8ohms Long reach in a small plier. Cat. T-3565 $.595° and a power rating of 5 watts Ideal for PA work, burglar alarms DIRECT IMPORT ALL ONE etc. It has a mounting bracket for easy installation and comes YOU REAP THE PRICE complete with lead Cat C-2705 $ 50 8FNFF/T! TOP 7 ea. JOYSTICK QUALITY SAVE Y áóH INTERFACE KIT NOISE PROBLEM? $2.00 Calling ell System 80 owners: isn't it c pain in $825 the neck using the arrow keys to play BEAT IT WITH THESE games? Wouldn't you rather use a Joystick control? Cat K-3455 SUPPRESSORS oti - STORE T e last Great Here's your chancel This kit allows you to add a Inline Distributor Suppressor STOCK joystick to your System 80 via the printer port - Connect anywhere in lead to eliminate ONLY Aviation and here's the good news: This month only or reduce distributor noise. we're GIVING A FREE 'OUICKSHOT JOYSTICK Cat Adventure with each Interface kill That's right, save an A-7904` A special Plug souvenir edition of Dick amazing $24.95 - this month only! Spark Noise Suppressor Smith's solo round-the -world heli- A spark plug cap with inbuilt copter flight, with pictures, maps, OYFR 2.00FOR 50K resistor. Cat A-7908 $1.00 flight details etc. of this historic 8 record -breaking flight Cat B9100 WORTH FOR Generator Noise Suppressor Heavy duty 0.5 uF-100 volt The kt JUST grejitONLY s37 ° capacitor., Cat A-7902 804 $1 50 QUICK SHOT Alternator Noise Suppressor EXPERIMENTERS A capacitor type suppressor with three leads. Reduces or eliminates the whine. TRANSCEIVER JOYSTICK Cat A-7924 ¡`$`80 Here's one for all the amateurs, It must be the ultimate joystick :. V /Dick Smtth _ 1 Delux Alternator Suppressor servicemen, technicians etc. Famous Features: 'Contour grip, rubber suction cups to hold it A coil type filter wound on a high density ferrite National brand 9 channel CB, Flight Cap 27MHz +y'' down during those tight movements. It's just core. Cat A-7926 ideal for conversion to 10 meters, use $350 1 Vey like the real one in a helicopter. Suit VIC and $11.95 as spare parts, experiment with etc. ' Atari, or System 80 (see above). Coax Alternator Suppressor We over -bought on this model and we `Cat Y-1000 Cat Y-1495 Normally $24.95 Heavy duty 0.5uF 50 volt coaxial capacitor for MUST reduce stocks- our loss is your or FREE with extreme cases of alternator whine. Will handle the above gain. Take advantage of our mistake Transmitting 60 amps. Cat A-7928 and Interface Kit. $5.50 save a fortune! Cat D-2500 Valves HURRY!. Replacements for when STRICTLY LIMITED STOCK yours stop working. Now sacrificed 6146B....Cat 0-7202 WAS 995 at only S1 $4995 6SJ6C .... Cat 0-7204 > 14" .r..r ,4011 1 UN; - 9,Q1-.picK544 poor /44" \tste 1`ts'` otichoCtco e, 6 ty Ppate ape' round- A6 2t. ELECTA:. 14.",,,o, o e NI eF Function Generator Every hobbyist every laboratory, every serviceman needs an audio signal generator. Why not one better, a function generator? Here's the superb Dick Smith Function Generator kit: amazing specs for such a low price! 20Hz to 170kHz in three ranges Sine, triangle & square wave output Sine wave distortion less than 0.7% at l kHz Cat K-3520 Negligible overshoot droop or ringing 240V operated Other kits around sell for $180 and more ... compare our low, low price! s x.599 Why pay more? 01K - 'ITH ELE _ TRONICS STORE LOCATIONS MAJOR RESELLERS Atherton Old: Maaraterfs Music Centre. 55 Man St 91 1208 Cairns Old Electronic World Shop 27 K Mart. Westmut Plaza Musgrave Rd 51 8555 Bailin* NSW: A NSW Parramatta Rd & Melton St AUBURN 648 0558 Coffin -rings b Co 91-93 River St 86 2285 Cairns Old Thompson Instrument Services. 79- T55 Terrace Level BANKSTOWN SG 707 4888 81 Mcleod St. 51 2404 Colts Harbour NSW. Colts Harbour Electronics 3 Coifs Plaza, Park Ave 5684 Darwin N T.: Kent Electronics, 42 Stuan Hwy, 81 4749 Darwin 613 Princess Hwy BLAKEHUAST 546 7744 52 N.T.: Ventronics 24-26 Kavanagh St Deniliquin NSW: Den Electronics 220 Cressy St Oxford and Adelaide Sts BONDI JCT. 387 1444 81 3672 East Maitland NSW: East Maitland Electronics. Cnr. Laws fi High Sts 33 7327 St WA KB 818 George St BROADWAY 211 3777 J Echuce VIC: Webster Electronics. 220 Paáenhare Gereldton Electronics Et Manne 361 Main Terrace 21 2176 Gladstone Old Purely Electronics Shop 2. Cre. 531 Pittwater Rd BROOKVALE 93 0441 Herbert B Auckland Sts 72 4321 Costord NSW.. Tonarrov/s Electronics 6 HFFi 68 147 Hume Hwy CHULLORA 642 8922 Wdhann St 24 7246 Kingston TAS: Kingston Electronics, Channel Cart 29 6802 Launceston TAS: Advanced Electronics Sa The Quadrant 31 7075 'lunar, NSW: Deco 162 Pacific Hwy GORE HILL 439 5311 Electra, 3a/6-18 CanintonSt Mackay Old Stevens Electronics. 42 Victoria St 51 1723 315 Mann St GOSFORD 25 0235 STORE Maryborough Old Keller Electronics. 218 Sdelaiie SL 21 4559 Mt Gambier SA Hutchessods St 6404 Mildura VIC McWJgam Electronics. 40 Elizabeth Dr & Bathurst St LIVERPOOL 600 9888 Comm. 5 Elizabeth 25 HOURS lemon Ave 23 6410 Morwell VIC Morwell Electronics. 128 George St 34 6133 Lane Cove & Waterloo Rds NORTH RYDE 88 3855 Nanbour Wit Nambour Electronics. Shop 4. Iowan House Ann St 41 1604 Orange All Dick Smith Stores are George & Smith Sts PARRAMATTA 689 2188 NSW. MAW Electrons, 173 Summer St 62 6491 Penrith NSW: Atom Electronics open for trading during the Shop 12, 541 High St 36 1466 Port Macquarie NSW Hat of Electronics. 73 Horton St The Gateway, High & Henry Sts PENRITH 32 3400 83 74409 Rockhampton Old: Purdy Electronics. 15 East St 21 058 Sheppanon normal trading hours for their 6 Bridge St SYDNEY 27 5051 VIC G.V Ekctronics Centre, 189b Caro St 21 8866 Southport QId: Amateurs Paradise. particular area (either 9-5.30 121 Nerang St 32 2644 Toowoomba Old Hunts Electrodes, 18 Ned St 32 9677 125 York St SYDNEY 267 9111 or 8.30-5). Many stores are Townsville Old Tropical TV. 49 Fulham Rd Vincent Vrsage 79 1421 Wagge NSW Tamworth Arc & Kable Ave TAMWORTH 66 1961 Wagga Wholesale Electronics 82 Forsyth St Wodonga VIC AbM Electrones, 78a Hqh also open for late right tally. St 24 4588 Whyalla SA Melia Enterprises Shop 2, Forsythe St 45 4764 173 Maitland Rd TIGHES HILL 61 1896 Please rig the store concerned 263 Kiera St WOLLONGONG 28 3800 for their particular hours. a1 ACT Gladstone St FYSHWICK SPEEDY PHONE/BANKCARD 96 80 4944 , VIC 260 Sydney Rd. COBURG 383 4455 ORDER SERVICE Nepean Hwy & Ross Smith Ave FRANKSTON 783 9144 Just phone your order and Bankcard 4% .4. details - its so simple! 205 Melbourne Rd. GEELONG 78 6766 399 Lonsdale St MELBOURNE 67 9834 we orne here (02) 888 2105 Bridge Rd & The Boulevarde RICHMOND 428 1614 ORDER ONLY ON THIS NUMBER Terms available to ENQUIRIES: (02) 888 3200 Springvale & Dandenong Rds. SPRINGVALE 547 0522 approved applicants r. (LLD 293 Adelaide St BRISBANE 229 9377 through... HEAD OFFICE AND MAIL ORDER CENTER: 166 Logan Rd BURANDA 391 6233 P.O. Box 321, NORTH RYDE, NSW 2113. Gympie E Hamilton Rds CHERMSIDE 59 6255 TEL. (02) 888 3200 Bowen & Ruthven Sts TOOWOOMBA 38 4300 POST & PACKING CHARGES Ingham Rd & Cowley St West End TOWNSVILLE 72 5722 ORDER VALUE CHARGE ORDER VALUE CHARGE 55.00-S9 99 52 00 550.00-599 99 S5 00 SA Wright & Market Sts ADELAIDE 212 1962 510.00-524.99 S3 00 S100 00 or more 56 50 Main South & Flagstaff Rds DARLINGTON 298 8977 525 00-S49 99 S4 00 Changes are nr goods sent by you o Aunrava on - not armat o erseas or real 'wont Main North Rd & Darlington St ENFIELD 260 6088 WA Wharf St & Albany Hwy CANNINGTON 451 8666 100%1;°,7°" Dear Customers, Quite often, the products we advertise are so popular they nn out weber a few days Or untorseen Ave William St & Robinson PERTH 328 6944 crrcumstances might hold up shrpments so that advertised lens are not es the stores by the tone Centreway Arc, Hay St PERTH 321 4357 the advert appears And very occaamap, an error mght slip through our checks and appear in the advert after all wire human toll Please doll blame the store manager of stall: they cannot TAS 25 Barrack St HOBART 31 0800 solve a dock strike on the ether side of me world or fix an error that's appeared re prod II yogi re about to dine across town to peck up an advemsed km, why not play it sale and give the store a call lest. ..lust In case THE AUSTRALIAN Thanks Dick Smith and Staft COMPANY Communications NEWS Marconi Radio Society re -launches historic callsign The callsign used to introduce Britain's first scheduled radio entertainment broadcast, 2MT, will be heard on the amateur bands later this year after a 60 -year break in transmission. British Home Office cations Year' has been given Britain), the company was later approval has been granted for wholehearted support by authorised to recommence the use of the callsign G2MT Marconi Space & Defence transmissions. I) 1. by the Marconi Radio Society, Systems Limited. And so, the first scheduled en- a group formed recently by As well as enjoying the use of tertainment broadcast in the UK amateur radio enthusiasts the company's facilities at Stan - was transmitted on 700 metres employed at the Stanmore more, the Society's Patron is from Writtle, near Chelmsford, (UK) headquarters of Marconi General Sir Harry Tuzo and its on 14th February 1922 under the - LsfC` Space & Defence Systems Ltd President Dr. W. Bardo, Chair- callsign 2MT ('Two-Emma- and at other company sites in man and Technical Director re- Tock'). The 'G' (for England) has _ .r15Gzq`7Y the locality. spectively of MSDS. now been added to accord with The callsign will be used at Marconi's Wireless Telegraph current practice. Radio amateur Stanmore for the first time at Company Limited was first The licence restricted broad- canonised 1200 hours BST on Saturday 2nd granted an experimental licence casting to half an hour each July 1983 using equipment in the summer of 1920 to use the Tuesday evening and the station The first licensed radio owned and operated by members. callsign to introduce news bul- was required to cease transmit- amateur to become a saint is The frequencies used will de- letins. ting for three minutes in every Father Maximilian Kolbe, pend on the prevailing propaga- This permission did not appa- ten. These frequent intervals SP3RN, who died at the in- tion conditions but it is hoped to rently extend to music, even in were spent in checking to hear famous Auschwitz death organise contacts with amateur the accompanying role, and the whether any complaints had camp on 14 August 1941. radio clubs affiliated to the BBC licence was swiftly revoked fol- been received. and with similar groups within lowing the broadcast of'dramma The broadcasts provided Fr Kolbe spent several years as the GEC -Marconi organisation. per musica' by a Danish tenor. amateurs with invaluable check- a missionary before starting his The founding of the Marconi Following representations to ing references and their content amateur radio activities in 1938. Radio Society and its authorisa- the then Postmaster General by set the pattern for later public He was arrested by the Gestapo tion to use the historic callsign the Wireless Society of London broadcasting programmes; for in 1939 and sent to Auschwitz, G2MT during 'World Communi- (now the Radio Society of Great example, the first radio play was near his home parish of Krakow. produced (Cyrano de Bergerac) In 1941, when one of his fellow and a rudimentary 'Children's prisoners, who was the head of a Synthesised HF transceiver from JRC Hour' was evolved before trans- large family, was selected for missions ceased in January 1923. death, Fr Kolbe volunteered to go The compact JST-100 HF transceiver employs an 8 -bit in his place. He was executed on microprocessor to control all the complicated functions 14 August that year. such as band and mode selection and memory channel Fr Kolbe was posthumously access. awarded the highest Polish military medal, the Virtuti Militarta Golden Cross. Pope The 11 -channel memory can John Paul canonised Fr Kolbe as easily store and recall not only a saint on 10 October 1982, thus VFO frequencies but also work- making him the first licensed ing frequency bands and modes. radio amateur to become a saint. Ilox Radio Corn in. r The JST-100 is fully equipped ,--"-- = - with capabilities such as three I'LL circuits phase -locked with a Delsound get highly stable 10 MHz standard A.E.A. crystal oscillator; two digital VFOs permitting independent Melbourne -based Antenna selection of bands and modes, Engineering Australia Pty and memory finder capability to Ltd has announced the recall any stored frequency with appointment of Delsound the working VFO being held. Pty Ltd as distributor of Features available include: circuit of narrow BPI.' type; large microphone, hand microphone A.E.A. products in Queens- fully digital 10 Hz -step syn- multi -function display; remote and key. land. thesiser; digital two-VFO control of frequencies and modes; Further details about this ex- Delsound will hold stocks of system; 11 -channel memory; overmodulation indication; citing rig are available from A.E.A. and memory antennas clamps, etc. finder capability; easy unique ALC input; frequency V icom, 57 City Rd, South Contact at Delsound is Bud tuning with main dial and up - data output. Melbourne Vic. 3205. Brances Pouncett. Phone Brisbane down buttons; easy -to -operate Options include a power sup- i n Sydney, NSW and Lower Hutt, 229-6155, or call at 1 Wickham panel design; receiver input ply, antenna tuner, speaker. desk N.Z. Terrace, Brisbane. ETI July 1983 - 141 Latest Bearcat slashes the price of scanning porch. It 200FB offers a great deal to the Available through Dick right hand side of the The Bearcat Smith stores, this latest Bear - employs sensor -touch fledgling scanning enthusiast for $349. Here's a cat features a 16 -channel operation and the loudspeaker released rig. memory (with battery back- 'bips' when you press the keys. quick review of this recently up), auto or manual search Internally, it appears a well - over three bands (66-88 MHz, constructed unit, all the electron- 138-174 MHz, 407-512 MHz), ics being on a single printed direct channel access, auto- circuit board. matic channel lockout and On the air, the unit proved to priority functions plus pat- be very sensitive, easily pulling ented selective scan delay so in signals from base stations you don't miss the reply on 50 km away on just its own tele- two-way conversations. scopic whip. Programming it is a i The rig can be operated direct breeze. from the vehicle battery, or from The handbook that comes with the mains using a commonly it is clearly written, well set out available plugpack. It comes and easy to use. complete with its own telescopic The display is a little hard to antenna, which suits desk -top see with light directly falling on operation of the unit, and an ex- it, but if you locate the unit away ternal antenna socket so you can from direct light, there's no prob- really 'pull in' those signals from lem. In any case, the same goes an outside antenna. for many other scanners we've We jumped at the opportunity seen. to review one of these rigs and The handbook warns of here's what we found. 'birdies' - spurious signals, The Bearcat 200FB is a com- generated within the receiver, pact plastic -cased rig, measuring and conveniently lists them, thus just 235 mm wide by 220 mm enabling you to avoid them. We deep by 70 mm high. A 'porch' at had a look at them and looked up the front contains the controls our frequency table and think and a sloping panel from the top they should not be troublesome. to the porch contains the 9 -digit Basically, the Bearcat 200FB fluorescent display. is a delight to use, offers many The volume and squelch knobs useful features and is worthy of at the left are well -designed, just serious consideration if you're right for thumb -and -forefinger looking for a scanner and don't operation. The programming want to pay 'big bucks'. keyboard occupies most of the JIL SX-200 A BETTER SCANNING MONITOR RECEIVER. COVERS 26-88 MHz & 108-180 MHz & 380-514 MHz Monitors over 33,000 frequencies from 26 to 88 MHz, 108 to 180 MHz and 380 to f 514 MHz. Bands included within this range are HF and UHF CB, 27 and 155 MHz 4 MARINE, Australian LOW BAND. AIRCRAFT band. VHF SATELLITE band, 10 Mx. 6 Mx. 2 Mx and 70CMx AMATEUR BANDS, VHF High BAND as well as UHF two-way band. ar ó!1!:1: Mechanically rugged the SX-200 uses high quality double-side Epoxy -Glass printed circuit boards throughout. Some of Its other outstanding features include 3 MODE SQUELCH circuitry which allows the lockout of spurious and carrier only signals, extremely low spurious count AM and FM detection on all bands, FINE TUNING control for off channel stations, 240 VAC or 12 Volt DC operation, Accurate QUARTZ CLOCK, Squelch 1771. operated OUTPUT for switching a tape recorder etc, 16 Memory channels, MEMORY BACKUP, which lasts up to two years, high SENSITIVITY and SIGNAL-TO-NOISE ratio on all bands, CRYSTAL FILTER for excellent SELECTIVITY and easy servicability due to ú i !25 v"úQU component layout as well as a 90 day warranty. Its high quality and performance is testified by the fact that it is in use by a large number of -0 .O,M. ,1.200 State government and Federal bodies including most state and federal police departments. Contact GFS, the Australian Distributors, or our interstate outlets for full technical ...._... r=... . specifications. We also market a range of pocket scanning receivers and transceivers. Contact us for full details. PRICE $599 INC. S.T. + $12 P&P; SERVICE MANUAL $12 + $1.50 P&P; GFS Electronic Imports SCAN -X BASE ANTENNA $62 + $10 P&P. EXP-32-32 CHANNEL MEMORY 15 McKeon Road, EXPANDER KIT $53 + $5 P&P. A4 -AM AUTO AM KIT FOR AIRBAND $32 Mitcham, 3132, Vic. + $5 P&P. INTERSTATE DEALERS: NSW: (02) 211-0531; QLD: (07) Telex 38053 GFS Phone: (03) 873 3939 397-0808; SA: (08) 269-4744. 142 - July 1983 ETI SCANNERS' WORLD Dream Machine This rig must surely rate as every scanning en- r thusiast's 'dream machine'. It's just about got everything that opens and shuts. The J.I.L. SX-400 scanning extra 12 spot frequencies can be receiver offers continuous received up to 3.7 GHz! A demod- 1 1 coverage from 26 MHz to ulator for multiplex trans- 520 MHz in 12 bands. AM and mission is also available. FM detection, two scan rates Definitely for the scanner who (4 & 8 ch/sec), 20 memory must hear everything! Further channels and an IEEE stan- details available from the dard interface buss. Australian agents, GFS Elec- An optional -extra converter tronic Imports, 15 McKeon can extend this coverage to Rd, Mitcham Vic. 3132. 800 MHz in 480 channels and an (03)873-3939. New high gain directional antennas GFS Electronic Imports of Mitcham, Victoria, recently an- nounced the release of high 2!' 5 8150 moon two gain broadband directional antennas designed for use in a wide variety of VHF/UHF ODEON applications. - Particularly for 0, - It suited scan- Its boom length is just over 3 m. ning receiver use, both models Both antennas are also quite provide excellent performance in suited to transmission applica- fringe areas when compared with tions over their designed band- a standard discone (such as the width. Maximum input power Scan -X). handling is given as 200 watts. « Known as the LOG -S and the The LOG -S and LOG -SP are « i LOG -SP, the new antennas are of both available exclusively the log periodic type. The Model through GFS Electronic Imports LOG -S has nine elements with a or any of their agents. Price of the t9r.be'' SEP claimed gain of 911 (9 dBi) and a LOG -S is $89 plus $10 freight, bandwidth from 100 to 520 MHz. and the LOG -SP is $125 plus $10 Boom length is 1.02 metres. freight. The LOG -SP has a bandwidth For further information, con- from 65 to 520 MHz, comprises tact GFS Electronic Imports, 13 elements and features a 15 McKeon Rd, Mitcham Vic. claimed gain of 101 111.5 dBi). 3132. (03)873-3939. INTERESTING MARITIME CHANNELS Here is a short list of interesting maritime channels for scanning The scanner's manual enthusiasts in Sydney and Melbourne. The shore stations are .1.. located Dick Smith's Australian OL.-0500 near the harbourside so you need to be in close range to 5111114" get good reception or at a high location if you're some distance Radio Frequency Handbook, DICK away from the harbour in either city. 2nd Edition, must surely be Sydney the `text' every scanner 156.375 MHz FM Navigation warning should have. 156.525 FM Maritime search & rescue Written by scanner expert', Jack McDonald, this 170 -page - x State 's plus book contains a wealth of . 156.650 FM Maritime Services Board i y 156.800 FM Weather information on scanning, includ- u,q ing a detailed table of fre- 454.000 FM State Maritime Services Board a,wo¡ ; 454.275 FM State Maritime Services Board quencies and services you'll find on the VHF and UHF bands. Melbourne There are 15 short chapters at MHz 156.400 FM Harbour control the start of the book that explain. I -` 156.550 FM Harbour control in simple language, all the basics 6, 156.600 FM Harbour control you need to know to get into ¡¡ó 156.700 FM Harbour control scanning. 498.650 FM Sea pilots The book shows you how to 5 McOar.m 493.475 FM Sea pilots build yourself a simple antenna. a., .r.:...... ,a ...,.r rote, . .t.,wo We would welcome more contributions to this column, particularly how to install a scanner in a car from the other states. Send your contributions to: The Editor, and how to interpret the various Enquire at any Dick Smith store 'Scanners' World', ETI Magazine, PO Box 21, Waterloo NSW codes you hear used on the air. or Dick Smith Electronics, 2017. The book costs $12.95 and is P.O. Box 321, North Hyde listed as catalogue No. B-9600. NSW 2I 13. ETI July 1983 - 143 SHOPAROUND This page is to assist readers in the continual search for components, kits, printed circuit boards and other parts for ETI projects and circuits. If you are looking for a particular item or project and it is not mentioned here, check with our advertisers. ETI-464 general At this stage, we have no indi- purpose IC audio cation of who'll be stocking kits, but Rod Irving Electronics is amplifier probably a good place to start. This project will doubtless be Parts shouldn't be too difficult widely stocked as a kit. At the to obtain. The CA3100 wideband time of going to press, the fol low- op -amp, which forms the heart of ing firms indicated they'd be the unit, is distributed by AWA stocking kits: Altronics in Microelectronics in Sydney Perth, Dick Smith Electronics (021638-9022. Radio Despatch stores everywhere, Electronic and Jaycar in Sydney stock the Agencies in Sydney and Rod device and possibly Rod Irving Írving Electronics in Electronics in Melbourne. Melbourne. You might also try The 2N3866 and 2N2905A All Electronic Components in complementary high speed Melbourne. output devices are widely Almost any electronics compo- stocked. The Thermalloy slip-on nent supplier will stock the heatsinks we used on these uA380 or LM380 IC and pc boards transistors in the prototype, part The mighty monitor! The Micron 300 mm (12") green screen monitor must offer will be stocked by the suppliers no. 2228B, are distributed by just about the best value for money you can get in a computer monitor. Whilst it does listed at the end of this column. Soanar Electronics. feature 10 Hz to 20 MHz bandwidth and high resolution, like many others you see feature of 'reverse picture' capability. By simply turning up If you want a negative or posi- Printed circuit boards will be around, it has the unique the brightness and turning back the contrast - presto, instant black -on -white! tive transparency to make your available from the suppliers The display area will show 24 lines of 80 characters and the resolution is claimed own pc board, one can be ob- listed at the end of this column. to be 800 lines at the centre. It takes composite video input (neg. sync.), 70 ohms tained for $1.50 post paid from: For those of you making your terminated, 10k unterminated. It has a full complement of trace geometry controls ETI-464 Artwork, ETI Maga- own pc board, a same -size posi- and an auxiliary unfiltered rectified output that can deliver 12 Vdc. (That could be zine, P.O. Box 21, Waterloo NSW tive or negative transparency handy!). 2017. Make cheques payable to can be obtained for $2.85 post The review model was delivered by Jaycar and we couldn't wait to fire it up on the 'ETI Artwork Sales' and ensure paid from: ETI-1520 Artwork, lab MicroBee. Needless to say, it performed very well indeed. In fact, we could hardly Box 21, believe the 'Beé s VDU output was so good! you ask for a positive or negative, ETI Magazine, P.O. Micron green screen monitor should be directed to Jaycar in Make Enquiries for the according to what you need. Waterloo NSW 2017. Sydney or Altronics in Perth. cheques payable to 'ETI Artwork ETI-465 loudhailer Sales' and ensure you ask for a positive or negative. as you want. As this uses the ETI-464 module, money orders payable to 'ETI Radio Despatch Service the above item applies. If you ETI-265 `power down' Artwork Sales' and ensure you 869 George St want to use the sensitive and effi- ask for a positive or negative, as Sydney NSW 2000 cient Benelec 8-224 horn recom- timer you want. mended in the article, we know There's nothing in the way of Rod Irving Electronics in that at least Electronic 'special' components used this Printed circuit board 425 High St should have little Agencies in Sydney will be project, so you and panel suppliers Northcote Vic. 3070 stocking it. In Melbourne, ask for difficulty getting the parts to- it at Rod Irving Electronics or gether. We understand kits will Almost every pc board ever All Electronic Components. be stocked by Jaycar in Sydney, published by ETI may be ob- James Phototronics Kits in one form or another Altronics in Perth and Rod Irv- tained Groin the following suppliers: 522 Grange Rd will be stocked by Dick Smith ing Electronics in Melbourne. Fulham Gardens SA 5024 stores, Electronic Agencies in All Electronic Components in All Electronic Components Sydney, Rod Irving Elec- Melbourne may also stock kits. 118 Lonsdale St tronics in Melbourne and possi- The Unibox case we used for Melbourne Vic. 3000 Jemal Products bly Altronics in Perth and All our prototype (P/N 144) is P.O. Box 168 Victoria Park WA 6100 Electronic Components in stocked by Magraths in Mel- RCS Radio Melbourne. bourne but a wide variety of 651 Forest Rd Jaetronics Batteries and battery holders cases may be used - even the Bexley NSW 2207 to suit this project are widely ubiquitous jiffy box! Jaycar 58 Appian Drive stocked in electronics stores. l'he stock a new range of smart all - Panels, ureter scales and dial St Albans Vic. 3021 ABS plastic water pipe and caps plastic ABS eases, of which the faces for almost every E'l'l project can be obtained from most hard- HB6150, 1, 2, 3 series totange, published nary also be obtained Sunbury Printed Circuits ware stores. grey, blue. black) would suit.. from the above two firms. Lot 14, Factory 3 Printed circuit boards will be For pc boards produced over McDougall Rd ETI-1520 wideband available from the suppliers the last three to live years, the Sunbury Vic. 3429 listed at the end of this column. If following suppliers generally amp you're making your own board keep stocks on hand: Billco Electronics This useful little project will be- and want a positive or negative Electronic Agencies Shop 2, 31 Pultney St the output stage of our up- same -size transparency, one can Dandenong Vic. 3175 come 1 15-117 Parramatta Rd coming lab. standard function be obtained for $1.85 post paid Concord NSW 2137 and pulse generator. However, it Ilom E'l'l -265 Artwork, E'l'l and Mini Tech has many other uses, as sug- Magazine, P.O. Box 21, Waterloo 117 York St P.O. Box 9194 gested in the article. NSW 2017. Make cheques or Sydney NSW 2000 Auckland N.Z. 144 - July 1983 ETI S- S Save time and trouble with mail order. Just fill out the coupon on page 152 BASIC ELECTRICITY/ELECTRONICS VOL 4 HANDBOOK OF RADIO, TV, INDUSTRIAL 8 21504P 514.75 TRANSMITTING TUBE & VALVE EQUIVALENTS electronics Volume 4 covers construction, operation and usage of BP2 52.25 electronic test instruments. Included are analogue and Equivalents book for amateurs and servicemen, More than digital multimeters, vacuum -tube textbooks voltmeters, oscilloscnpes, 18 000 old and new valves from UK, USA, Europe, Japan tube and transistor testers, bridge Instruments and signal el al. CV (military) listings with commercial equivalents generators. included. BASIC ELECTRICITY/ELECTRONICS VOL 5 RADIO AND ELECTRONIC COLOUR CODES 21505P 59.95 AND DATA CHART The last volume In this series explains the principles of BP7 S1.60 motors and generators. Devices covered Include AC and This large wall chart covers all colour codes in use ELECTRONICS ITS EASY VOL. 1 - 55.95 DC motors and generators, three-phase systems and power throughout the world. For all radio and Meters, resistance, capacitance and inductance, emitter electronic com- converters. The final chapter covers servo control systems. ponents made in UK, USA, Europe and Japan. followers, op amps, power supplies and electronic filters. ESSENTIAL THEORY FOR THE ELECTRONICS HOBBYIST THE CP/M HANDBOOK WITH MP/to ELECTRONICS - IT'S EASY VOL. 1 $12.95 2288 $4.32 Same content in a hard-cover form. This book supplies the electronics hobbyist with the back- 88048A 519.95 how ground knowledge which will exactly suit their specific 1 I Shows you to use CP/M (control program for requirements. Minimum maths. microprocessors) and its resources. No prior knowledge of computers ELECTRONICS - IT'S EASY VOL. 2 55.95 is assumed. CP/M is available on nearly all Digital sub -systems counters and shift registers, A -D and computers using the 8080, 8085 or Z80 microprocessors. D -A conversion, digital instruments and test equipment, BEGINNER'S GUIDE TO DIGITAL ELECTRONICS computers, transmission links and oscilloscopes. BP61 $3.36 Covers all essential areas including number systems, ' FIRST BOOK OF TRANSISTOR EQUIVALENTS codes, constructional and sequential logic, analogue/ AND SUBSTITUTES ELECTRONICS- IT'S EASY VOL. 2 512.95 digital/analogue conversion. BP1 53.36 Same content In a hard -cover form. This guide covers many thousands of transistors showing A MICROPROCESSOR PRIMER possible alternatives and equivalents. Covers transistors BP72 55.92 i ELEMENTS OF made in UK, Japan, USA, Germany, France, Europe, ELECTRONICS Learning about microprocessors is easy with this book, This is Hong Kong and includes types produced by more than series an introduction to modem electronics. All the written in a style that is easy to follow. The maths shortcomings of 120 different manufacturers. Is taught as the reader progresses. The course tnis basic machine are discussed and the reader is concentrates shown on the understanding of concepts central to how these are overcome by changes to the Instruction set. electronics, rather than digressing over the whole field. Relative addressing, index registers follow as logical The author where anticipates difficulties lie and guides the progressions. SECOND BOOK OF TRANSISTOR EQUIVALENTS reader through them. AND SUBSTITUTES BP14 BOOK 1 55.92 Interchangeability data BP62 covers semiconductors 57.52 manufactured all over the world. Immediate equivalents All fundamental theory necessary to full understanding of are shown and possible substitutes are included. simple electronic circuits and components. reference BOOK 2 and data handbooks BP63 57.52 GIANT CHART- RADIO, ELECTRONICS, Alternating current theory. SEMI -CONDUCTORS 8, LOGIC SYMBOLS BP27 $1.92 BOOK 3 AUDIO CYCLOPEDIA Identify those symbols at a glance. A must for beginners BP64 S7.52 20675P 566.00 and advanced enthusiasts alike. Professionals can always Semiconductors technology leading to transistors and ICs. A complete, In-depth look at the art of audio - from the hide it in their desks) basic principles of sound to solid-state and integrated BOOK 4 circuits. Over 3000 entries and hundreds of Illustrations BP77 59.76 and circuit diagrams cover acoustics, amplifiers, record- RESISTOR SELECTION HANDBOOK ing, Microprocessing systems and circuits. reproduction, test equipment, audio measurements, BP28 52.24 and much more. Shows how to combine two preferred values of resistor to BOOK 5 obtain virtually any required value of resistance. Includes information about fixed resistors, standard ranges, colour BP89 $9.76 REFERENCE DATA FOR RADIO ENGINEERS 5 codes and markings, power ratings and resistor Communications. 21218P 54.50 calculations. The largest and most comprehensive collection of equations, graphs, tables, and other reference data BASIC ELECTRICITY/ELECTRONICS VOL 1 ELECTRONIC CALCULATOR USERS' HANDBOOK needed in general radio engineering and design. Contains 21501P 513.25 hundreds monographs, BP33 55.12 of charts, diagrams, curves, tables Presents First volume of five volume set provides thorough theoretical and illustrations. formulae, data, methods of calculation, con- and practical background to the overall sublect of electricity version factors, etc, for use with the simplest or most and electronics. sophisticated calculators. Includes the way to TUBE SUBSTITUTION HANDBOOK calculate using only a simple four -function calculator: trigonometric 21746P $8.75 BASIC ELECTRICITY/ELECTRONICS VOL 2 functions, hyperbolic functions, logarithms, square roots Complete, accurate, up-to-date to 21502P guide direct substitutes and powers. 514.95 for receiving and picture tubes. Contains over 6000 Volume 2 in this series builds on the basic information in receiving tube substitutes, over 4000 monochrome and Volume 1 by giving detailed information on AC and DC colour picture tube substitutes, and 600 communications AUSTRALIAN MICROCOMPUTER HANDBOOK circuits - covering series and parallel circuits, electro- substitutes. Also includes for quick pinouts operational 72505 NOW magnetism, resistance, capacitors and inductance plus checks. 515.00 associated calculations. Normally 525.00. A detailed buyer's guide to micro- computer systems and application packages in commercial, CONTEMPORARY MATHEMATICS FOR ELECTRONICS BASIC industrial, scientific. educational and home/hobby areas. ELECTRICITY/ELECTRONICS VOL 3 70274P 21503P S29.75 514.95 This book is split into three sections. Direct current maths This, the third volume in this series, introduces valves and Introduces the student to the calculator, fractions and TRANSISTOR SUBSTITUTION HANDBOOK transistors -from an introduction to vacuum tube through dimensional analysis. Alternating current maths covers 21515P $8.75 multi -element tubes, semiconductor devices, power phasors, quadratics and RMS in both sine and digital 17th edition - Accurate transistor substitution in a matter supplies, amplifiers, oscillators, pulse circuits - to special waveforms. Active device maths Introduces number of seconds with this replacement listing of over 19 000 semiconductor devices. systems and boolean. American and foreign bipolar transistors. ETI July 1983 - 145 ELECTRONIC PROJECTS FOR BEGINNERS 28 TESTED TRANSISTOR PROJECTS PRACTICAL ELECTRONIC CALCULATIONS BP48 S4.64 2218 54.32 & FORMULAE This book gives the newcomer to electronics a wide range Some circuits are new, others are familiar designs. BP53 59.76 of easily built projects. Actual components and wiring Projects can be split and/or combined for specialised For the practical persons workbench. Bridges gap layouts aid the beginner. Some of the projects may be built needs. between technical theory and cut-and-dried methods without using soldering techniques. which work but leave the experimenter unfulfilled. There's and higher maths avoided a strong practical bias. Tedious POPULAR ELECTRONIC PROJECTS 50 CMOS PROJECTS where possible. BP49 54.96 224B 54.64 the most popular types of circuits and Many interesting and useful projects multivtbrators, EQUIVALENTS GUIDE A collection of - INTERNATIONAL TRANSISTOR projects to interest most electronics constructors. The amplifiers and oscillators; trigger devices; special devices. 59.76 BP85 projects cover a wide range and are divided into four basic Companion to BPI and BP14 equivalents books, but con- and equipment. types: radio, audio, household test AUDIO HI-FI PROJECTS tains a huge amount of information on modem transistors MAJOR SOLID STATE produced by over 100 manufacturers. Wherever possible, BP29 53.04 ' BEGINNERS GUIDE TO DIGITAL ELECTRONICS equivalents are subdivided into European, American Three projects for the more experienced constructor: BP61 53.36 and Japanese types. Also shown are the material type, 12.5 stereo amplifier, eight input stereo/mono mixer Covers all essential areas including number systems, W /ch polarity, manufacturer and indication of use or application. 4x14 W quadraphonic amplifier. Full constructional codes, constructional and sequential logic, analogue/ and digital/analogue conversion. details provided. HOW TO IDENTIFY UNMARKED ICS BP101 52.46 ; ELECTRONIC GAMES BUILD YOUR OWN METAL AND This shows the reader how, with just a test -meter, HOW TO chart BP69 S5.92 about recording the particular 'signature' of an TREASURE LOCATORS to go How to build many interesting electronic games using IC which should enable the IC to be identified BP32 55.92 unmarked modern ICs. both simple and complex circuits for with reference to manufacturers or other data. Covers Electronic and practical details on the simple and beginner and advanced builder alike. inexpensive construction of heterodyne metal locators. FOR BEGINNERS RADIO CONTROL HOW TO MAKE WALKIE-TALKIES BP79 55.92 $5.12 with details of BP43 How complete systems work constructional low power transmitter -receivers (walkie- receivers. Also included This treatise on solid state transmitters and - talkies) covers many aspects from licensing requirements meter, crystal controlled superhet antennas, field strength and bands, through practical circuitry and construction to controls. Section dealing with electro -mechanical the various types of aerials that may be used. electronics licensing etc. not applicable to Australia. PROJECTS IN OPTO -ELECTRONICS for beginners EASY ELECTRONICS -CRYSTAL SET CONSTRUCTION i. 11 56.56 á BP45 55.92 BP92 Included are simple circuits using ordinary LEDs as well as who wish to participate in the intricacies of For those more sophisticated designs such as infra red transmitters electronics more through practical construction than by and detectors, modulated light transmission and also theoretical study. The circuits are based on those from modem photographic projects etc. BEGINNERS HANDBOOK OF IC PROJECTS earlier publications but have been modified to use home wound coils. .. 74286P 519.25 inexpensive components and the fundamentals of The novice is guided in mastering POPULAR ELECTRONIC PROJECTS building, troubleshooting and testing electronic projects. IC PROJECTS FOR BEGINNERS BP49 54.96 In addition to many elementary projects, more advanced BP97 S6.56 the most popular types of circuits are included concerning bipolar integrated circuits Especially written for the less experienced hobbyist, and Includes a collection Of ones radio, household projects and medium and large-scale integrated circuits. offers a range of fairly simple projects based around and projects which cover audio, a number of popular and inexpensive linear and digital and test equipment. HI-FI LOUDSPEAKER ENCLOSURES ICs. Complete layout and point-to-point wiring diagrams included. 2058 $3.36 SINGLE IC PROJECTS Data for building corner reflex, bass reflex, exponential BP65 55.12 ELECTRONICS IT'S EASY VOL. 1 55.95 horn, folded horn, tuned port, Klipschom labyrinth, tuned - IC. A few Simple to build projects based on a single loaded multi speaker panoramics. Clear Meters, resistance, capacitance and Inductance, emitter column, port and projects use one or two transistors as well. A strip board included followers, op amps, power supplies and electronic filters. dimensioned diagrams layout is given for each project plus special constructional and setting up info. Contents include low level audio IT'S EASY VOL. 1 512.95 SOLID STATE NOVELTY PROJECTS ELECTRONICS - audio power amps, timers, op-amps and in hard form. circuits, 219B 53.04 Same content a -cover miscellaneous circuits. A number of novelty projects using modem ICs and tran- IT'S EASY VOL. 2 55.95 sistors. Includes 'Optomin' -a musical instrument played ELECTRONICS - ELECTRONIC GAMES hand, water warbler for Digital sub -systems counters and shift registers, A -D and by reflecting a light beam with your BP69 S5.92 LEDs and ladders game, D -A conversion, digital instruments and test equipment, pot plants, music tone generator, A number of interesting electronic games projects using roulette wheel, etc. computers, transmission links and oscilloscopes. touch switch, electronic Cs for both the beginner and advanced enthusiast. RECEIVERS ELECTRONICS ITS EASY VOL. 2 512.95 SOLID STATE SHORTWAVE - ELECTRONIC HOUSEHOLD PROJECTS Same content in a hard -cover form. FOR BEGINNERS BP71 55.92 222B 54.32 Most useful and popular projects for use around the home. Design and construction of several solid-state shortwave HOBBY ELECTRONICS PROJECT BOOK 54.95 Includes two-tone buzzer, intercom, smoke and gas receivers giving high level of performance yet utilising Fifty projects ranging from very simple ones for complete detectors, baby alarm, freezer alarm etc. etc. relatively few inexpensive components. beginners to more elaborate ones for those with more experience. There's a complete guide to soldering and REMOTE CONTROL PROJECTS BUILDING instructions on how to make your own pc boards. BEGINNERS' GUIDE TO BP73 56.56 ELECTRONIC PROJECTS Covers radio, infra -red, visible light, ultrasonic controls. 2278 $5.12 HOW TO BUILD ELECTRONIC GAMES 53.95 Full explanations are provided so that the reader can Enables total beginners to tackle electronic projects. Alien invaders, electronic die, sound effects, two slot car adapt the projects for domestic and industrial as well as Includes component identification, tools, soldering, build- controllers, electronic poker machine, the family ferry and model use. ing methods, cases, legends, etc, etc. Practical basic lots more. projects are included. POWER SUPPLY PROJECTS HOW TO BUILD GOLD AND TREASURE BP76 55.92 DETECTORS ESSENTIAL THEORY FOR THE ELECTRONICS 53.95 This book gives a number of power supply designs, HOBBYIST Tells you how metal detectors work and how to construct including simple unstabilised types, fixed voltage regulated 2288 $4.32 the different types of detectors: discnminating, BFO, types and variable voltage stabilised designs. The designs induction balance and a professional deep -seeking This book supplies the electronics hobbyist with the back- unit. are all low voltage types for semiconductor circuits. ground knowledge which will exactly suit their specific How to build a geiger counter. requirements. Minimum maths. POPULAR ELECTRONIC CIRCUITS - BOOK 1 BP80 56.56 RADIO AND ELECTRONIC COLOUR CODES Yet more circuits from Mr. Penfold! Includes audio, radio. AND DATA CHART test gear, music projects, household projects and many BP7 51.60 more. An extremely useful book for all hobbyists, offering This large wall chart covers all colour codes in use constructional projects remarkable value for the designs it contains. throughout the world. For all radio and electronic components made in UK, USA, Europe and Japan. ELECTRONIC PROJECTS USING SOLAR CELLS general BP82 56.56 FIRST BOOK OF PRACTICAL ELECTRONIC PROJECTS Includes a number of projects that benefit from solar power BP23 52.72 and obviate the problems encountered with batteries, Full constructional data, circuits, components lists for such as weight and bulk, frequency of replacement, and many practical projects including audio distortion meter, DESIGN OF TRANSISTOR CIRCUITS, failure when batteries are exhausted. superFET receiver, guitar amp. metronome, etc. WITH EXPERIMENTS 21626P 520.75 DIGITAL IC PROJECTS RESISTOR SELECTION HANDBOOK A self -teaching course in transistor circuits - seven BP84 $6.56 BP28 52.24 chapters explore the fundamentals of active semi- Companion to No. 225 Practical Introduction to Digital ICs Shows how to combine two preferred values of resistor conductors and their operating principles and procedures. and BP61 Beginner's Guide to Digital Electronics. The to obtain virtually any required value of resistance. Experiments in design and semiconductor testing provide projects included in this book range from simple to more Includes information about fixed resistors, standard hands-on experience. . advanced projects - some board layouts and wiring ranges, colour codes and markings, power ratings and diagrams are included. resistor calculations. BUILD YOUR OWN HI-FI & AUDIO ACCESSORIES 220B $3.04 AUDIO PROJECTS HOW TO BUILD YOUR OWN METAL AND Essential for keen hi-fi and audio enthusiasts. Projects BP90 $6.56 TREASURE LOCATORS include stereo decoder, three -channel mixer, FET preamp Covers a wide range of audio projects including pre- BP32 55.92 for ceramic pick-ups, mic preamp with adj. bass. stereo amplders and mixers, power amplifiers, tone controls and matching layouts wiring Electronic and practical details on the simple and dynamic noise limiter, loudspeaker protector, voice - etc. A number of board and diagrams are included. inexpensive construction of heterodyne metal locators. Is operated relay, etc. deoo3ó% 146 - July 1983 ETI LOOK! More books! mail order coupon on page 152 DESIGN OF VMOS CIRCUITS, WITH EXPERIMENTS 21686P $ma17.50 The authors look at the technology ELECTRONIC TIMER PROJECTS which makes dratic CMOS COOKBOOK advancements possible with VMOS, BP93 and show how these 56.56 21398P components can easily and effectively These may have S19.25 be integrated into a high degree of accuracy with quartz This book explains CMOS technology and its application common Circuit designs to enhance their responses. control or they may be quite simple designs, using only a to 'real world' circuitry. A mini -catalogue is Included, few components. which A number of specialist timer projects lists over 100 devices, giving their pinouts and application IC OP -AMP COOKBOOK are car windscreen wiper delay unit, darkroom timer, notes. 21695P metronome etc. S23.75 Basic op -amp theory in detail, with 200 practical, illustrated IC TIMER COOKBOOK circuit applications: JFET and MOSFET units are featured, ELECTRONIC PROJECTS FOR AND CARS BOATS 21416P plus manufacturers' data sheets and company addresses. BP94 S15.95 56.56 Gives you a look at the hundreds of ways IC timers Fifteen fairly are simple projects designed for use with 12 V used in electronic instrumentation. EXPERIMENTS IN ARTIFICIAL INTELLIGENCE electrical systems but in some cases can also be FOR SMALL COMPUTERS employed with 6 V and/or positive earth systems as well. IC CONVERTER COOKBOOK 21785P 513.25 21527P Artificial intelligence is the MODEL RAILWAY PROJECTS $20.75 capability of a device to perform Written for the practising engineer, technician, hobbyist or functions normally associated with human BP95 intelligence. S6.56 student, this book will be an invaluable working guide to With this book, a small computer with extended BASIC Projects include such things as controllers, signals and the understanding and use of IC analogue/digital and and some knowledge of BASIC language, you can sound effects units. Construction stripboard layouts are digital/analogue converters. cointelligence.nductinteresting and exciting experiments in artificial provided for each project. DESIGN OF OP -AMP CIRCUITS, WITH EXPERIMENTS CB PROJECTS 21537P S16.50 PRACTICAL SOLID-STATE CIRCUIT DESIGN BP96 56.56 The design of the fundamental circuits that are the basic 21787P $14.95 A number of useful designs include a speech processor, building blocks of more sophisticated systems. A series of An introductory course in practical solid-state circuit interference filters and a simple CB radio receiver. Strip - 35 experiments illustrates the design and operation of design for the experimenter, designer or technician who is board layouts, wiring diagrams and notes on construction linear amps, differentiators and integrators, voltage and interested in constructing tailor-made circuits. are provided. current converters, active filters, and lots more. SCRS AND RELATED THYRISTOR DEVICES POPULAR ELECTRONICS 555 TIMER CIRCUITS - BOOK 2 APPLICATIONS SOURCE BOOK, 21806P $19.25 BP98 57.52 WITH EXPERIMENTS Written for experimenters, technicians and engineers, this A companion for BP80, this book provides a wide range of 21538P S11.25 book is a practical and comprehensive guide to theory, designs for electronics who enthusiasts are capable of This book describes the construction of the 555 timer and operation, specifications and applications of silicon - producing working projects from just a circuit diagram controlled rectifiers related gives numerous practical examples of its applications in all . (SCRs) and thyristor devices. without the aid of detailed constructional information. areas of electrical and computer engineering, including 17 simple experiments. REGULATED POWER SUPPLIES MINI -MATRIX BOARD PROJECTS 21808P $29.75 BP99 56.56 DESIGN OF ACTIVE FILTERS WITH EXPERIMENTS Comprehensive discussion of the Internal architecture This book provides a selection of 20 useful circuits which 21539P S15.95 and operation of the latest solid-state regulators. Explains can all be built on a mini -matrix board which is just 24 holes Introduction to the theory, implementation and design of when regulated supplies are needed and how to incor- by 10 copper strips in size. Simple and easy for those with active filters using the 741 op-amp. porate them in your projects, and discusses modem not much experience In electronics. circuitry including linear and switching circuits and late Z80 MICROCOMPUTER DESIGN PROJECTS ICs. MULTI -CIRCUIT BOARD PROJECTS 21682P 520.75 BP103 ANALOG INSTRUMENTATION FUNDAMENTALS S6.56 This book provides a complete look at the internal All circuits are based 21835P on one specially designed pc board. architecture of the Z80, the heart of many microcomputers, 529.75 Recommended to the less experienced hobbyist. and even shows how to build a microcomputer, the EXBO, Numerous practical, hands-on lab experiments and using this powerful chip. solved problems are included, plus discussions of move- ments, dc ammeters, voltmeters, ohmmeters, bridges, AERIAL PROJECTS filters and attenuators. No calculus is required. BP105 $6.56 DESIGN OF PHASE -LOCKED LOOP CIRCUITS, Practical aerial designs including active, loop and ferrite WITH EXPERIMENTS RF CIRCUIT DESIGN which are relatively simple and inexpensive to build. The 21545P 21868P S33.95 complex theory and mathematics $15.95 of aerial design have An excellent introduction to A practical approach to the design of RF amplifiers, been avoided. the theory, design and implementation of phase -locked loop circuits using impedance -matching networks and filters. Uses a minimum various TTL and CMOS devices. Includes manufacturers' of complex maths. MODERN OP -AMP CIRCUITS data sheets and describes the use of breadboarding aids BP106 56.56 in the wide range of laboratory -type experiments. SOLAR CELLS A collection of widely varying circuits and projects based 22270P 537.95 on the op -amp ICs. AUDIO IC OP -AMP APPLICATIONS In-depth description of the basic operating principles and 21558P $13.25 design of solar cells. It also covers the techniques HOW TO GET YOUR ELECTRONIC PROJECTS WORKING This book discusses IC op -amps and their application In currently used to produce solar cells and reviews system BP110 $6.56 audio systems, and describes the numerous advantages applications. Heips you to overcome the problems of a circuit that of using op -amps, including small spatial needs, low doesn't work by indicating how and where to start looking power consumption, reliable performance and low cost. ELECTRONIC DESIGN WITH OFF -THE -SHELF ICS for many of the common faults that can occur when Assumes a basic understanding of op-amp theory. 50274P $14.70 a building up project. It contains virtually all the information you need to design UNDERSTANDING CMOS INTEGRATED CIRCUITS and build electronic circuits, systems and subsystems with 21598P S9.95 readily available ICs. Shows how to interlace them into This book tells you what CMOS ICs are, how they work, highly complex systems. and how they can be used in electronic circuit designs. circuit techniques Many practical circuits, complete with parts values, MODERN FILTER DESIGN are included. 94663P 549.95 and This book details the advances in active RC filters, botn design DESIGN OF TRANSISTOR CIRCUITS from a practical standpoint and from a state-of-the-art WITH EXPERIMENTS point of view. It is the first book that gives detailed analysis 21626P $20.75 and design procedures for switched capacitor filters. A sell -teaching course to provide the background and UL COOKBOOK explanations necessary to teach the reader the art of 50 PROJECTS USING CA3130 ICS 21035P 517.50 designing transistor circuits. 2238 54.32 A complete look at TTL logic circuits - what TEL is, how it The CA3130 is an advanced operational amplifier capable works, and how to use it. Many kinds of practical TTL are GUIDE TO CMOS BASICS, CIRCUITS, of higher performance than many others: circuits often included, such as digital counters, electronic stopwatches, AND EXPERIMENTS need fewer ancillary components. Audio projects. RF digital voltmeters, etc. 21654P $14.95 projects. Test equipment. Household projects. Misc. If you are already familiar with TTL devices and are ready projects. ACTIVE -FILTER COOKBOOK to examine the benefits of CMOS, this book is your 21168P 521.95 complete source. It tells you what CMOS devices are, their PRACTICAL INTRO TO DIGITAL ICS Learn how to construct filters of all kinds - highpass, Characteristics and design rules. 22 experiments demon- 2258 $4.32 lowpass, bandpass. The book is easy to understand - no strate the concepts discussed. Introduction to digital ICs (mainly TEL 7400). Besides advanced maths or obscure theory is used. simple projects, includes logic test set to identity and test PRACTICAL TRANSFORMER DESIGN HANDBOOK digital Cs. Also includes digital counter -timer. 21657P UNDERSTANDING IC $35.50 OPERATIONAL AMPLIFIERS An easy lo understand, illustration -filled guide 50 CIRCUITS USING GERMANIUM, SILICON 21511P to 510.25 designing and constructing transformers. Reviews the AND ZENER DIODES Latest edition of this book covers theoretical practical and fundamentals of electricity, magnetism and algebra needed BP36 53.36 aspects of operational amplifiers and associated circuits. to understand transformer theory, and This edition covers general 50 interesting and useful circuits and applications using includes material on BiFET and BiMOS and design considerations, transformer types, power losses the CMOS op -amps. germanium and silicon signal diodes, silicon rectifier and transformer use in converters and Inverters. Ir...a diodes and zener diodes etc. ETI July 1983 - 147 ,111" ETI CIRCUITS BOOKS 1/2/3 52.95 ea 50 PROJECTS USING RELAYS, SCRS AND TRIACS Many of these circuits have been published in the 'Ideas BP37 55.92 for Experimenters' section in ETI. electronic Practical working circuits using silicon controlled rectifiers, relays and bi-directional triodes. With a minimum of ea music/audio/video difficulty you can use them in motor control, dimming and ETI CIRCUIT TECHNIOUES VOLS 1/2 $4.75 heating control, timing and light sensitive circuits, warning The how, what, which, where, why and how much anthology devices and many others. of electronic components, circuits and techniques. 50 FET PROJECTS 3 54.95 I ETI CIRCUIT TECHNIQUES VOL BP39 $5.92 converters, test equipment, Projects include smelters and CHEAP VIDEO COOKBOOK receiver aids, mixers and tone tuners, receivers and $11.75 The PET used is not critical. This book is 21524P controls etc etc. new, low-cost way to get words, interest and value to SW listeners, radio amateurs, hi-fi Complete discussion of a of your and onto any enthusiasts and general experimenters. pictures and opcode out of computer ordinary TV screen, using a seven -IC easy -to -build circuit which you can build for less than $20. 50 SIMPLE LED CIRCUITS VIDEO 8P42 53.36 equipment AN INTRODUCTION TO 50 interesting and useful circuits and applications using test BP100 $6.56 is for the LED. Also includes circuits for the 707 Common Anode This book is written in layman's language and Display for the beginner and advanced enthusiast. and fault finding anyone who is thinking about buying or renting or who has just bought or rented a video recorder and wants to get the best out of the machine. IC555 PROJECTS AUTOMOTIVE TUNE-UP AND EMISSION MOBILE DISCO HANDBOOK 56.56 BP44 CONTROL SERVICE BP47 54.64 how life went on before the 5551 Included One wonders 21712P 520.75 Most people who start mobile discos know little about circuits, motor car and model are basic and general Car owners who wish to save money and maintain their equipment or what to buy. This book assumes no pre- and noise makers plus section on railway circuits, alarms cars at peak performance will learn from this book how to liminary knowledge and gives enough info to enable you to and 559s. subsequent 556, 558 adjust, repair and maintain the systems that ensure best have a reasonable understanding of disco gear. operation. PROJECTS IN OPTO -ELECTRONICS TROUBLESHOOTING WITH THE OSCILLOSCOPE AUDIO CYCLOPEDIA 566.00 BP45 55.92 21738P 515.95 20675P look the of audio from the Included are simple circuits using ordinary LEDs as well as Excellent for the professional service technician or the A complete in-depth at art - of sound to solid-state and integrated more sophisticated designs such as infra -red transmitters serious hobbyist, as it combines step-by-step procedures basic principles Over 3000 entries and hundreds of illustrations and detectors, modulated light transmission and also for using the scope with the specific nuts and bolts of TV circuits. photographic projects etc. receiver troubleshooting. and circuit diagrams cover acoustics, amplifiers, record- ing, reproduction, test equipment, audio measurements, and much more. MICROCOMPUTER DESIGN AND TROUBLESHOOTING 526.75 LM 3900 IC PROJECTS 21819P ELECTRONIC MUSIC CIRCUITS and BP50 54.64 Tells you how to design microcomputer systems 21833P $24.95 make them work without an expensive commercial Unlike conventional op -amps, the LM 3900 can be used How to build a Custom electronic music synthesiser, development system or the need for costly test instrumenta- for all the usual applications as well as many new ones. outlines numerous Other circuit designs and then shows a complete description of It's one of the most versatile, freely obtainable and tion. The author also provides how to modify them to achieve particular responses. two popular microprocessors- the 8085 and the 6502. you inexpensive devices around. This book provides the Many of the circuits can be used as special -effects boxes groundwork for simple and advanced uses - it's much for guitars and other musical instruments. more than a collection of projects. Very thoroughly PRACTICAL REPAIR AND RENOVATION recommended. OF COLOUR TVS INTRODUCTION TO ELECTRO -ACOUSTIC MUSIC BP34 54.32 81515P S15.95 This book shows how to obtain a working colour TV for This book assumes no previous technical knowledge. It very little outlay by repairing and renovating a set that has discusses the relationship between the technology and 50 CIRCUITS USING 7400 SERIES ICS been 'written of by a dealer. Includes practical details of the composition of eiectro-acoustic music. BP58 55.12 how to construct your own CRT tester/rejuvenator and 50 interesting and useful circuits and applications using cross hatch generator. MODERN RECORDING TECHNIQUES these inexpensive and versatile devices. 21037P 519.25 TRANSISTOR RADIO FAULT-FINDING CHART Explains the equipment controls and techniques found in a modem recording and how to use them creatively BP7D S1.92 studio and correctly to produce a desired result. Numerous 50 CMOS IC PROJECTS Used properly, this chart should enable the reader to trace photographs, diagrams and charts. 224B 54.64 most common faults quickly. Across the top of the chart Projects include multivibrators, amplifiers and oscillators, ,. are four rectangles containing brief descriptions of the trigger devices and other special devices. faults. Selecting the appropriate fault, the reader simply SOUND SYSTEM ENGINEERING follows the arrows and carries out the suggested checks in 21156P 532.50 sequence until the fault is cleared. Dealing with audio systems as a whole, it includes installing and equalising the sound system and interfacing the acoustic systems. Instrumentation, the SECOND BOOK OF CMOS IC PROJECTS ELECTRONIC TEST EQUIPMENT CONSTRUCTION electrical and designing for acoustic gain are BP75 S5.92 acoustic environment and BP59 55.12 covered. Leading on from book number 224 '50 CMOS IC Describes construction of wide range of test gear including PROJECTS', this second book provides a further FET amplified voltmeter, resistance bridge, field strength SUBSTITUTION HANDBOOK selection of useful circuits mainly of a fairly simple nature. indicator, heterodyne frequency meter etc. TUBE Contents have been selected to ensure minimum overlap 21746P 58.75 between the two books. POWER SUPPLY PROJECTS Complete, accurate, up-to-date guide to direct substitutes BP76 55.92 for receiving and picture tubes Contains over 6000 receiving tube substitutes, over 4000 monochrome and COUNTER DRIVER AND NUMERAL DISPLAY PROJECTS Includes simple unstabilised types, fixed voltage regulator picture and 600 communications types and variable voltage stabilised designs. The designs colour tube substitutes, BP67 55.92 substitutes. Also includes pinouts for quick operational features and are all low voltage types for semiconductor circuits. Well-known author F.G. Bayer applications checks. projects using various types of numerical displays, popular counter and driver ICs, etc. HOW TO GET YOUR ELECTRONIC PROJECTS WORKING HOW TO BUILD SPEAKER ENCLOSURES BP110 56.56 VMOS PROJECTS Helps you to overcome the problems of a circuit that 20520P 58.75 $6.56 doesn't work by indicating how and where to start looking A practical guide to the whys' and 'hows' of constructing BP83 high -quality top -performance loudspeaker enclosures. Though primarily concerned with VMOS power FETs and for many of the common faults that can occur when their applications, power MOSFETs are dealt with too, in a building up a project. chapter on audio circuits. Projects Include audio circuits, ACTIVE -FILTER COOKBOOK sound generator circuits, dc control circuits and signal 21168P 521.95 circuits. USE OF THE OSCILLOSCOPE Learn how to construct filters of all kinds - highpass, 39389P $27.95 lowpass, bandpass. The book is easy to understand - no Programmed instruction course for use in a basic electrical theory is DIGITAL IC PROJECTS advanced maths or obscure used. engineering laboratory course. Author assumes basic BP84 $6.56 knowledge of DC and AC circuits but none of oscilloscopes. ACTIVE WITH EXPERIMENTS Helps the reader to develop a knowledge of the workings DESIGN OF FILTERS This is an essentially practical course - thoroughly 21539P 515.95 of digital circuits. Board layouts and wiring diagrams are recommended. included. Introduction to the theory, implementation and design of active filters using the 741 op -amp. HOW TO USE OP -AMPS TEST GEAR METERING AND POWER SUPPLY - j ...t BP88 57.52 PROJECTS $3.00 AUDIO IC OP -AMP APPLICATIONS Design notes and applications on many topics including Includes many types of meters, audio noise and signal :1 21558P 513.25 basic theory, amplifiers, power supplies, audio circuits, generators, simple CMOS tester, oscilloscope calibrator This book discusses IC op -amps and their application in oscillators, filters, computers and control engineering. It s etc. audio systems, and describes the numerous advantages written around the 741 IC but includes design notes for of using op -amps, including small spatial needs- low reliable performance and low cost. most of the common op -amps. TEST GEAR - VOL. 2 $3.95 power consumption, Projects include audio oscillator, transistor tester, true Assumes a basic understanding of op -amp theory. ELECTRONIC TIMER PROJECTS RMS voltmeter, RF signal generator, versatile logic test BP93 $6.56 probe, microwave oven leak detector etc. VIDEO TAPE RECORDERS These may have a high degree of accuracy with quartz 21521P 517.50 control or they may be quite simple designs, using only a ELECTRONIC PROJECTS FOR YOUNG In this completely revised second edition, the author tells few components. A number of specialist timer projects are SCIENTISTS $3.95 in simple language how helical VTRs work and how to car windscreen wiper delay unit, darkroom timer, . PH meter, geiger counter, helium-neon laser, sound level operate and service them. Includes numerous examples metronome etc. 9 ti? meter, solar cells, negative ion generator and much more. of circuits and mechanical systems. 148 - July 1983 ETI USING THE 6800 MICROPROCESSOR 21512P 513.25 This will guide the reader through the conception, configuration, writing and running of a variety of programs More that demonstrate practical OOPSI books! use of a 6800 system. Z80 MICROCOMPUTER DESIGN PROJECTS 21682P S20.75 mail This book provides a complete look at the internal order coupon on page 152 architecture of the Z80, the heart of many microcomputers, and even shows how to build a microcomputer, the EX80, using this powerful chip. ELECTRONIC MUSIC AND CREATIVE TAPE RECORDING A MICROPROCESSOR PRIMER BP51 MICROPROCESSOR CIRCUITS VOL. 1 S5.92 BP72 $5.92 Shows how electronic music can be made at home with Learning about 21877P S14.75 microprocessors is easy with this book, Presents the simplest and most inexpensive of equipment. written in a style that is easy to follow. The basic microprocessor concepts in simple shortcomings of language for Describes how the sounds are generated and how these this basic machine discussed beginners and teaches you to construct a are and the reader is shown useful microcontroller may be recorded to build up the final composition. how these are overcome by to the system. Offers 30 demo circuits changes instruction set. which take you through Relative addressing, index registers follow logical assembly, operation and pro- as gramming of a PRACTICAL CONSTRUCTION OR PREAMPS, progressions. microcontroller. TONE CONTROLS, FILTERS, ATTENUATORS INTERFACE PROJECTS FOR THE BP60 AN INTRO TO BASIC PROGRAMMING TECHNIQUES APPLE II S4.96 69387P This book shows the enthusiast how to construct a variety BP86 515.95 $6.56 A series of interface projects that of magnetic tape recording, microphone and disc pre- Ideal for beginners seeking to understand and program are easily built and In enable the user to realise the computer's amplifiers, and also a number of tone control circuits, BASIC. Book includes program library for biorhythms, potential through project construction. Projects rumble and scratch filters, attenuators and pads. graphing Y against X, standard deviations, regressions, are primarily hardware - orientated, with some software supporting the generating musical note sequences, and a card game. hardware. ELECTRONIC SYNTHESISER PROJECTS PET INTERFACING BP81 BEGINNING BASIC S5.92 21795P For the electronic music an 39806A S19.95 S25.25 enthusiast, invaluable Demonstrates how to build numerous reference. This is full Intended for beginners with no Interfacing devices book of circuits and information on computing experience, one for hardware. BASIC how to build analogue should be able to intelligently PET language programs are used delay lines, sequencers, VCOs, program In BASIC in a short throughout, and the book envelope shapers, The time. includes a discussion of the etc. etc. author takes a clear and microprocessors Internal architecture logical approach to and general the subject that should enable the hardware/software interfacing. average enthusiast to understand and build up what BEGINNING FORTRAN appears to be a quite complex instrument. 46011A 519.95 6809 MICROCOMPUTER PROGRAMMING AND Starts with simple and elementary examples proceeds to INTERFACING, WITH EXPERIMENTS AUDIO PROJECTS intermediate level programs. Also includes references, 21798P BP90 56.56 tutorials, flow charts, deck set-ups and matrix algebra. $21.95 a solid Covers a wide range of audio Gives understanding of how to program and projects Including interface the preamplifiers and mixers, power tone high-performance 6809 microprocessor. The amplifiers, controls UNDERSTANDING COMPUTERS author and matching etc. A number of layouts wiring completely explores internal structure, addressing board and 39815A $17.95 modes, diagrams are included. data movement instructions, registers, arithmetic This book describes how computers work. For people who logic and test instructions for the 6809. use small computers, it starts with the most elementary ELECTRONIC MUSIC PROJECTS gates works and up to the complete computer. Gives an Z80 MICROCOMPUTER HANDBOOK BP74 understanding of languages and how they in the 55.92 operate 21500P Provides constructors with practical for the less computer. 517.50 Circuits This thorough handbook hardware, complex music equipment including fuzz box, waa-waa covers software and microcomputers built around the Z80. pedal, sustain unit, reverb and phaser, tremolo generator NAILING JELLY TO A TREE etc. Text covers guitar effects, general effects, sound 39842A $24.95 THE S100 AND OTHER MICRO BUSES generators, accessories. This guide to software teaches you machine about 21810P language, assembly language programming and BASIC. 513.25 SONICS The key to 1982 YEARBOOK 55.35 The emphasis is not on learning to write programs but on successful computer expansion is a complete An interview with Kraftwerk, how to cope with recording, learning to use the thousands of available programs that understanding of the bus system, through which the lighting, rock acoustics. guitars, equipment reviews and have already been written. computer communicates with peripherals. This book will more. give you that understanding. PEANUT BUTTER AND JELLY GUIDE TO COMPUTERS SONICS MAGAZINE MICROCOMPUTER DESIGN AND 52.35 ea 39813A 514.95 TROUBLESHOOTING The Australian music magazine to the art and 21819P dedicated A simple, easy -to -digest source information on personal 526.75 craft of sound. Published Apnl, July, October, Yearbook in of Tells how computing for the potential buyer who is less than an you to design microcomputer systems and December. 515 for one Please indicate them year subscription. expert in the field. make work without an expensive commercial starting Issue. development system or the need for costly test instru- mentation. The author also provides a complete description INTRODUCTION TO WORD PROCESSING 3i of two popular microprocessors- the 8085 and the 6502. 88076A S17.95 Written for the non -technical reader, this book tells about '3H1.1 DON LANCASTER'S MICRO COOKBOOK, VOLUME 1 the concepts common to all word processing systems, 21828P then analyses all features in detail. '. $20.75 This 'cookbook' starts with the very fundamentals of microprocessors and microcomputers and takes computers YOUR you FIRST COMPUTER through number systems, codes, memory, etc, until you 88045A S12.50 can work intelligently with micros. for beginners An easy -to -understand beginner's book to small computers. Understanding them, buying them and using them for personal and business applications. MICROPROCESSOR CIRCUITS VOL. 1 21877P 514.75 COBOL FOR BEGINNERS FROM CHIPS TO SYSTEMS: AN INTRODUCTION Presents basic microprocessor concepts in straight- forward language for beginners. Teaches you to construct 39378P 521.95 TO MICROPROCESSORS a useful microcontroller system through progressive It is a solid text for introductory programming courses in 88063A $19.95 demonstration circuits. Cobol, using a format that is easy to understand, yet Explains exactly what a microcomputer system is and how comprehensive enough to make supplementary readings it works. Introduces fundamental concepts and covers all 8080 MICROCOMPUTER EXPERIMENTS unnecessary. aspects of microprocessors and related components: internal operation, memories, interfacing and system 39808A 529.50 This' hands on' includes THE PET PERSONAL COMPUTER FOR BEGINNERS development etc. book 105 experiments presenting programs and diagrams as required for clarification. 61827P 520.95 This handy guide is written for use with all varieties of PET COMPUTERS FOR EVERYBODY A STEP-BY-STEP INTRODUCTION TO computer, from the 2001 to the new Super original 8032 39849A PET. It is suited to novices with no practical expenence 58.95 8080 MICROPROCESSOR SYSTEMS In this and provides advice and practical examples. easy -to -understand book it is explained how a 39804A S16.95 computer can be used at home, in the office or at school. Doesnt require any electronics or computer background. Includes a consumer's guide to computer equipment that This book describes the 8080 architecture and Instruction BIG THINGS FROM LITTLE COMPUTERS will help the reader decide what to buy and who to buy set through simple examples. Some basic software is 77859P 519.25 it from. introduced. A layperson's guide to personal computing with all the basic information and lots of how examples of personal DIGITAL computers can be used. CIRCUITS WITH MICROPROCESSOR APPLICATIONS BEGINNER'S GUIDE TO DIGITAL ELECTRONICS 46032A $39.50 BP61 An introductory text, this book provides readers with the 53.36 basic ideas and needed Covers all essential areas including number tools to analyse and design digital systems, computers circuits and codes, constructional and logic, computer systems. Discusses micro- sequential analogue/ processor digital/analogue conversion. computer organisation, machine language hardware & techniques number systems and gate circuits. BEGINNER'S GUIDE TO MICROPROCESSORS MICROPROCESSOR INTERFACING TECHNIQUES 8 COMPUTING 88029A $24.95 BP66 S5.92 IAPX 88 BOOK Teaches you how to interconnect a complete micro- Introduction to basic theory and of binary 93016P S20.25 concepts processor system and interface it to the usual peripherals. arithmetic, microprocessor operation and machine This from Intel itself Intel book describes the unique 8088 The hardware and software skills needed to effectively language programming. Only prior knowledege in assumed microprocessor total detail. Absolutely invaluable for all interface peripheral devices are covered along with is very basic arithmetic a::"11 and an understanding of indices. involved with the 8088. various buss standards and A/D conversion. ETI July 1983 - 149 THE 68000: PRINCIPLES AND PROGRAMMING QWIKTRAN PRACTICAL INTRO TO DIGITAL ICS Ft' $19.95 21853P 519.95 39824A $4.32 for Micros, Minis and Main Frames. 225B An easy -to -read, systematic approach to the 68000 Quick FORTRAN to ICs (mainly TTL 7400). Besides of computing and Qwiktran, Introduction digital 16 -bit microprocessor. The book guides you Starts with the basic concepts includes logic test set to identify and test advanced FORTRAN IV. Lots of examples simple projects, through the complex architecture, instruction set. pinouts a fundamental subset of ICs. Also Includes digital counter -timer. proficiency. digital and interfacing techniques. Written for design engineers, to increase the reader's programmers and students. BEGINNER'S GUIDE TO MICROPROCESSORS THE UCSD PASCAL HANDBOOK 8 COMPUTING 35536P 523.75 BP66 55.92 PROGRAMMING IN BASIC FOR Language descriptions organised in a quick and easy Introduction to basic theory and concepts of binary PERSONAL COMPUTERS reference are given in this book for readers with no prior arithmetic, microprocessor operation and machine $14.75 experience of Pascal programming. is 30739P language programming. Only prior knowledge assumed Simple instructions show how to give BASIC commands indices. very basic arithmetic and an understanding of and statements a wide range of applications, from INTRODUCTION TO PASCAL programming video games to developing business or 91522P 519.95 A MICROPROCESSOR PRIMER scientific programs. The second edition of this popular book has been updated BP72 55.92 to conform to the new international standard of Pascal. Learning about microprocessors is easy with this book, The contents illustrate the design and construction of PROGRAMMABLE CALCULATORS written in a style that Is easy to follow. The shortcomings of Pascal programs, involving a wide range of basic com- this basic machine are discussed and the reader is shown 46008A 524.95 puter algorithms in a practical context. how these are overcome by changes to the instruction set. This book suggests which calculators to buy, their follow as logical and limitations, and the how -tos of pro- Relative addressing, index registers possibilities PASCAL gramming them. progressions. 46028A S19.95 For people with little or no programming experience, this TAKE A WITH YOUR CALCULATOR PRACTICAL COMPUTER EXPERIMENTS CHANCE book gives lots of examples that clearly explain proper 514.95 BP78 55.92 39807A usage of language features. Discusses top -down this book deals How to build typical computer Circuits using discrete logic. An introduction to modem mathematics, programming, debugging, self -documentation etc. This book is a useful intro to devices such as adders and with programming of programmable calculators and source book of logic circuits. includes probability problems. storers as well as a general THE PASCAL HANDBOOK 88053A 523.50 AN INTRO TO BASIC PROGRAMMING TECHNIQUES THE 6809 COMPANION book summarises the entire Pascal vocabulary, 56.56 This BP102 56.56 BP86 including the variations introduced by different com- in It is not a beginners introduction to microprocessors in Ideal for beginners seeking to understand and program mercial versions of Pascal. All in dictionary format. general but a discussion of the features of the 6809 and a BASIC. Book includes program library for biorhythms, programmer in particular. graphing Y against X, standard deviations, regressions, reference work for the 6809 PASCAL PROGRAMS FOR SCIENTISTS generating musical note sequences, and a card game. AND ENGINEERS COMPUTERS 8 COMPUTING BASIC FOR EVERYONE 88058A 523.50 YEARBOOK 1982 S4.95 most frequently used scientific algorithms. 61481P $19.75 Over 60 of the Includes disks, CP/M and your computer, learners along with their program implementation in Pascal, are in 349 pages of BASIC information for all purposes. microcomputer, programming in CHIP -8, alphasort, fast this book. plotter, PET talk, the System 80 etc. BEGINNING BASIC 39806A $19.95 TRS-80 COLOUR COMPUTER GRAPHICS Intended for beginners, this book discusses how a 97864P S21.95 programmer and a basic computer interact with the com- Explore the creative and maginative blending of computers software puter, problems likely to be met by the beginner, the need and colour. Shows how to create dynamic and interesting computing for and uses of documentation etc. graphics to enhance your own computer programs. FIFTY BASIC EXERCISES STARSHIP SIMULATION 88056A 517.95 39810A $11.95 Designed to leach BASIC through actual practice, this HOW TO WRITE AN APPLE PROGRAM book offers both a specific simulation which can be graduated exercises in math, business, This 92990P 523.25 book contains played, and a complete look at The programs implemented, modified and much a 'how-to' book. Author assumes only a minimal operations research, games and statistics. Very run with how to put together a simulation on almost any subject. familiarity with computer and BASIC. The book covers were designed to run directly on a TRS-80 and will program writing from initial minor or no changes on any system with Microsoft BASIC. every aspect of simple BASIC PROGRAMS FOR SCIENTISTS AND ENGINEERS Concepts to final debugging - wittily illustrated too! INSIDE BASIC GAMES 88073A 519.95 This book contains scientific and engineering application TO WRITE A TRS-80 PROGRAM 88055A 519.95 HOW programs written in BASIC. 92992P 523.25 The medium of games teaches readers how to design book is virtually identical to 'How to Write an Apple error -free, interactive BASIC programs. Rules, algorithms This COMPUTER GRAPHICS PRIMER Program (92990P) described above. Changes have been and coding differences for the PET, APPLE II and TRS-80 $21.95 made to allow for differences in the two machines and are also included. 21650P has a colour drawing, photograph. variations in BASIC. Also wittily illustrated! Almost every page MICROSOFT BASIC picture or a schematic to help you learn computer graphics and easily. Programming concepts apply to all TO WRITE AN IBM PC PROGRAM 39823A 519.95 quickly HOW microcomputers, and examples are given in BASIC for the 92991P S23.25 Includes branching and loops, arithmetic in BASIC, the a description Apple II. See above. strings, editing, arrays and files, disk and of the Radio Shack Level II BASIC. INTRODUCTION TO TRS-80 GRAPHICS USING THE UNIX SYSTEM INTRODUCTION TO FORTH 39818A $17.95 98162P S24.95 21842P S14.95 It begins with the basic concepts of line drawing and leads figure This book by Richard Gauthier of RGL has been written for The most complete book available on the MMS FORTH the reader on to geometric shapes, moving no people with some knowledge of computers, but with version of FORTH, but also a fundamental approach to animation and other more advanced topics. Specific knowledge of Unix. It is however also of value to programming in all versions of FORTH. Many program- Current Unix users. ming examples are provided, with direct comparisons to '", CIRCUIT DESIGN PROGRAMS FOR THE TRS-80 the Microsoft Level II BASIC version of these programs. 21741P 521.75 FILES APPLE A number of programs written to aid you in using your 523.25 90191P STARTING FORTH TRS-80 and Level II BASIC for the design and analysis of people who know some BASIC and would This book is for 42922P 523.75 many electronic circuits. The programs analyse inform- like to expand and apply this knowledge by using file integrated circuit A and complete guide to FORTH, this book covers ation on ms values, periodic waveforms, of the Apple. Includes programs for the clear capabilities fundamental principles and then a full set of high- timers and bipolar transistor circuits. Stock market. mailing lists, inventories, grades and It with advanced records. level FORTH commands. concludes medical techniques and style. MOSTLY BASIC: APPLICATIONS FOR YOUR TRS-80 CP/M PRIMER BOOK 1 A FORTRAN PRIMER - 21791P 521.95 21788P 519.25 80454P $6.95 A complete one -stop course on CP/M, the very popular 28 ready -to -use BASIC programs which have been Assumes no previous knowledge of program writing. II operating system for 8080, 8085 and Z80 -based micro- completely tested and debugged. Programs include a fundamentals the FORTRAN language, computers. Complete terminology, hardware and software covers the of telephone -watch, spelling test, house writing concentrates on dialler, digital stop concepts, startup of a CP/M system, and a complete list of enables extensive program and buying guide. mileage calculator, and others. Com- programming style. gas CP/M-compatible software. plete with explanations of each program, sample runs, and complete program listing. THE CP/M HANDBOOK (WITH MP/M) INTRODUCTION TO STRUCTURED FORTRAN 519.95 46007A 519.95 88048A MOSTLY BASIC: APPLICATIONS FOR YOUR TRS-80 Contains a step-by-step description of all the CP/M Written for the beginner, the text incorporates the command features. Designed for the beginner, the book new FORTRAN 77 with a discussion of structural pro- - BOOK 2 progresses to detailed explanations of the file transfer gramming. Includes a discussion of time-sharing, pseudo 21865P S19.25 program, the debugging program and CP/M's text editing language programming and WATFIV statements. 32 ready -to -run BASIC programs. including two to test program. your ability in history and maths. a Dungeon of Danger that's strictly for fun. eleven household programs, seven ASSEMBLY LANGUAGE PROGRAMMING your ESP level, and HOW TO GET STARTED WITH CP/M CP/M on money and investment. two to test 520.25 more. Complete with explanations, sample run and listing 39832A 519.95 88250P the user for each program This practical book eases the reader into the essentials of This valuable guide provides beginning computer learning language the system, giving an overview of the operating system, an with a hands-on method of assembly it and what it do for the programming. Very Mile prior knowledge is assumed either idea of what will be like to use can INTERMEDIATE PROGRAMMING FOR THE TRS-80 reader. of CP/M or assembly language programming MODEL I AUSTRALIAN MICROCOMPUTER HANDBOOK BEGINNING FORTRAN 21809P S14.95 72505 NOW 515.00 46011A $19.95 Step-by-step instructions for the TRS-80 user who wants Normally $25.00. A detailed buyer's guide to micro- Introduces readers to FORTRAN. Included are references to progress from BASIC to machine and assembly Model I system computer systems and application packages in commercial, for further study, brief tutorials on key punching, flow chart- language programming with the TRS-80 industrial, scientific, educational and home/hobby areas. ing, deck set-ups and matrix algebra. .-..d A complete how-to guide with numerous examples 150 - July 1983 ETI ...and for good computing for measure... business BASIC FOR ACCOUNTANTS 80098P S9.95 TRS-80 MORE PET GAMES AND RECREATIONS f3 - THAN BASIC Shows accountancy students and accountants how to use 95529P 21813P 518.85 a computer to perform the repetitive tasks associated with 515.95 Presenting an interesting mixture Learn to program in Z80 mnemonics by using the book's of diversions guaranteed record keeping, calculating and report writing. Using the to entertain and educate. Ideal for beginners, error -tolerant interactive monitor program. Over 26 com- yet also BASIC language attention Is concentrated on debtors, mands available, challenging to computer veterans, the book features inventory and general ledger with total documentation that helps you progressive systems. change the commands to meet levels of difficulty and five different types specific applications. of games. COMPUTER BASED BUSINESS SYSTEMS TRS-80 ASSEMBLY LANGUAGE MADE 80192P SIMPLE 32 BASIC 510.95 21851P PROGRAMS FOR THE PET COMPUTER A short Introduction 519.25 39825A to the sorts of systems used by a If you have an understanding of BASIC S29.50 ""` ' i typical business to handle Its typical activities. The book programming, this Each chapter fully documents book will help you learn to plan, write and hand -assemble a different bug -free aims at providing a general understanding and therefore program. If readers have a good working your own assembly language programs In memory, knowledge of avoids technological detail. using BASIC, they can and the T -bug and Level II BASIC ROM subroutines. devise Implement their own program changes. THE COMPUTER SOLUTION PROGRAMMING THE TRS-80 POCKET 80195P COMPUTER THE ATARI ASSEMBLER S13.50 30531P 513.25 It should be of interest to business people contemplating, 90236P 519.25 This book explains all aspects of problem -solving in Implementing or already using computer data processing This practical book gives detailed Instructions for using BASIC, and covers cassette machine interfacing and how the or to any non -technical person curious to know why and Atan Assembler cartridge for novices with some knowledge how to make the best use of the system's keyboard and display. computers are used in Australian businesses and of BASIC programming. Fundamental Information pro- organisations. gramming in assembly language is given. TRS-80 ASSEMBLY LANGUAGE SUBROUTINES SMALL BUSINESS COMPUTERS: A GUIDE 31188P I ATARI AND $19.25 GAMES RECREATIONS TO EVALUATION AND SELECTION A wide spectrum of applications is discussed in this book, 90242P which 519.25 81134P 514.95 provides easy -to-use routines that can be used as Beginners and advanced users can use the prepro- Ideal for the inexpérienced user, this text emphasises they stand or modified. grammed games in this book to improve their skill. Charts, management considerations In determining the feasibility, flash cards, an error dictionary and paper graph designs economics, evaluation, selection, contracts and 32 BASIC PROGRAMS FOR THE TRS-80 COMPUTER are among the features. practicality of installing a computer. 39827A $29.50 Programs for the TRS-80 Level II or Model Ill BASIC (with EXPLORE COMPUTING WITH THE TRS-80 SMALL BUSINESS COMPUTER SYSTEMS 16Kor more user memory). (AND COMMON SENSE) 81136P 514.95 96137P $17.95 APPLE BASIC This book provides a bridge between the accountant and This Introduction to microcomputers and the BASIC the DP professional explaining 39099P by every step of the trading 519.25 language is Suitable for novices and users of the TRS-80. and reporting process in DP terms. It is This book gives especially useful to the beginner a thorough Introduction to Among the topics covered are creating tables, arts and engaged in the BASIC people specification processor in auditing programming on an Apple computer, and covers graphics, games and simulation. DP accounting systems. all areas of programming, Including graphics, games, mathematical programs, and a great deal more. 32 BASIC GAMES FOR THE EXIDY SORCERER THE VISICALC BOOK - APPLE EDITION 39835A 529.50 98397P 522.25 CIRCUIT DESIGN PROGRAMS FOR THE APPLE II Full of programs with practical applications, educational If you your 21863P are using Visicale on Apple II and want to learn 523.75 uses, games and graphics. Each chapter documents a more about its expanded uses then this book will show you ready A series of -to -run Apple II programs ideal for different bug-free program. how to build a model, enter your and electronics data solve problems design engineers and others faced with about profit/loss projections, pdcing/costing estimates etc. solving problems related to plotting and verification of THE ART OF PROGRAMMING THE 1K ZX81 experimental data. The programs may be used as sub- BP109 S6.56 THE HANDBOOK (WITH routines in larger programs, CP/M MP/M) and many can be translated to This book explains how to use the features of the ZX81 run on other microcomputer systems. 88048A 519.95 including its random number generator, graphics and Containing a step-by-step description of all the timer. PEEK and POKE are explained and you should CP/M the APPLESOFT LANGUAGE command features, book progresses to detailed learn enough to develop programs of your own. explanations of the file transfer 21811P program, the debugging 513.95 program and CP/M's text editing program. Written for Apple II micros that use the Microsoft language, PROGRAMMING THE 6502 this introduction covers each aspect of programming in 88046A YOUR FIRST non -technical language, 518.95 COMPUTER from elementary concepts to Principles of assembly language for advanced techniques. programming the 88045A 512.50 6502 microprocessor are taught In this Introductory text. A beginner's guide to small computers, understanding Includes a discussion of trade-offs between hardware and them, buying them and using them for personal and APPLE MACHINE LANGUAGE software and detailed explanations of the 6502's internal business applications. Includes peripherals, languages 90230P 521.95 registers and buss operation. and application packages. This straightforward book teaches machine language programming through BASIC, the transition made being 6502 APPLICATIONS BOOK DON'T (OR HOW TO CARE FOR YOUR COMPUTER) step-by-step. Many sketches ) of video displays are 88015A $17.95 88065A provided, as well as exercises with answers. 516.95 Use this book and a few low-cost components to build a A guide to computer and peripheral preservation. Specific complete home alarm system, an electric piano, a motor advice for the floppy APPLE PASCAL computer, disks, hard disks, the CRT GAMES speed -regulator, a timeof-day clock, a simulated traffic terminal, the printer, tape units, the computer room, soft- 88074A 519.95 control system and a Morse code generator, etc. ware and documentation are included. Explore all the essential elements of UCSD Pascal and learn the Important Apple Pascal extensions. 6502 GAMES INTRODUCTION TO WORD PROCESSING 88023A 517.95 88076A S17.95 PASCAL PROGRAMMING FOR APPLE THE You learn how to play ten sophisticated games and also Written for the non -technical reader, this book tells about 95454P 518.95 learn assembly language programming. Also learn the concepts common to all word processing systems, then This book teaches UCSD Pascal on the Apple II. Many techniques of algorithm design and data structures. analyses all features in detail, from screens to scrolling examples, programs for financial applications, graphics, and formatting. Ile structures and sound reproduction are supplied. 8080 MACHINE LANGUAGE PROGRAMMING FOR BEGINNERS SMALL COMPUTERS FOR THE SMALL BUSINESSMAN 32 BASIC PROGRAMS FOR THE APPLE COMPUTER 39814A S12.95 39831A 524.95 38834A 529.50 The book will take the reader step-by-step through the The book tells readers how and where to shop for a Full of programs with practical applications, educational most common 8080 op codes and it will do so at a level computer successfully: what to expect their computer to uses, games and graphics. anyone can understand. do for them; how to select software; whether or not to use a consultant; how to introduce the computer to the staff and PET/CBM BASIC PROGRAMMING THE Z80 how much computer is necessary. 61751P 519.25 I 88047A 519.95 This book provides a thorough introduction to BASIC pro- This book will enable every reader to write complete appli- INVENTORY MANAGEMENT FOR SMALL COMPUTERS gramming on a PET computer, explaining programming cation programs for Z80 -based computer systems. 39848A S24.95 concepts for graphics, including three-dimensional letters, Includes exercises to measure progress and compre- Owners of retail businesses and their employees need this bar graphs and the use of sound effects in PET programs. hension at each level of programming. book. The program provides an inventory control system so that you know what stock is on hand, where it is located, THE PET PERSONAL COMPUTER FOR BEGINNERS PROGRAMMING THE Z8000 what price was paid for it and the selling price. 61827P 520.95 88072A S19.95 This handy guide is written for use with all varieties of PET A complete introduction to programming concepts and BASIC FOR BUSINESS FOR THE TRS-80 computer, from the original 2001 to the new 8032 Super techniques for use with the 16 -bit, Z8000 microprocessor. 90352P 522.25 PET. It is Suited to novices with no practical experience Presents detailed descnptions of the architecture and This book covers the application of BASIC language to and provides advice and practical examples. functions of this 'super chip'. business uses on the TRS-80 models II and III. PET BASIC 1 START WITH BASIC ON THE COMMODORE VIC 20 FROM THE COUNTER TO THE BOTTOM LINE 95524P S19.25 97070P $14.75 39811A $24.95 For users of the PET computer, this book covers such Helpful exercises and step-by-step instructions show you A demystifying guide to basic accounting needs and topics as creative graphics, humour and Interesting small >:;4 how to program in BASIC utilising all the graphic functions computer use. Includes inventory and purchasing, billing, programs. .k on the Vic 20. w accounts receivable, accounts payable and general ledger. ETI July 1983 - 151 INTRODUCTION TO AUTOMOTIVE SOLID-STATE LONG DISTANCE TV RECEPTION (TV -DX) THE OFFICE AUTOMATION PRIMER ELECTRONICS 515.50 BP52 56.56 31077P many and 21825P $14.95 i4 Written by UK authority, the book includes units the user step by step through all aspects of as welt as the home mechanic Guides devices made by active enthusiasts. A practical and For the professional - planning, evaluating and installing stages. Lively vignettes functions of most on -board automotive black authonative intro to this unusual aspect of electronics. explains the illustrate how automation increases productivity in word logic systems, including anti-skid braking. mail, boxes and and data processing, photocomposition, electronic electronic spark control, diagnostic systems and trip telecommunications, scheduling and message switching. INDUSTRIAL & computers. Probably the most comprehensive guide of its kind for HANDBOOK OF RADIO, TV, every manager seeking to maximise productivity and TRANSMITTING TUBE & VALVE EQUIVALENTS profitability. BP2 S2.25 More Equivalents book for amateurs and servicemen. than 18 000 old and new valves from UK, USA, Europe, (military) listings with commercial Japan et al. CV EXPERIMENTS IN ARTIFICIAL INTELLIGENCE equivalents included. FOR SMALL COMPUTERS 21785P 513.25 Artificial intelligence is the capability of a device to perform RADIO STATIONS GUIDE with human intelligence. $5.92 functions normally associated DX, BP55 With this book, a small computer with extended BASIC amateur radio, have a radio receiver. This is an aid for all those who of BASIC language, you can frequency and/or and some knowledge Shows the station site, country, interesting and exciting experiments in artificial Radiation Power of the conduct communications wavelength, as well as Effective intelligence. transmitter and in some cases, the station's call sign as well. TUBE SUBSTITUTION HANDBOOK AN INTRODUCTION TO RADIO DXING 58.75 $6.56 ELECTRONIC SECURITY DEVICES 21746P BP91 55.92 Complete, accurate, up-to-date guide to direct substitutes One section is devoted to amateur band reception and the BP56 6000 band reception, with Besides including both simple and more sophisticated tubes. Contains over 1 other section covers broadcast for receiving and picture and ultra-sonics, over 4000 monochrome and advice on suitable equipment and the techniques burglar alarm circuits using light, infrared receiving tube substitutes, for gas smoke detectors, picture tube substitutes, and 600 communications employed when using that equipment. The construction of - ' this book also gives circuits and colour doorphones, baby alarms, etc. substitutes. Also Includes pinouts for quick operational a number of useful accessories is described. flood alarms, fire alarms. checks. AERIAL PROJECTS RF CIRCUIT DESIGN BP105 $6.56 21868P S33.95 Practical aerial designs including active, loop and ferrite ELECTRONIC CALCULATOR USERS' HANDBOOK to the design of RF amplifiers. A practical approach which are relatively Simple and inexpensive to build. The BP33 $5.12 networks filters. Uses a minimum ' impedance -matching and complex theory and mathematics of aerial design have formulae, data, methods of calculation, con- maths. Presents of complex been avoided. version factors, etc, for use with the simplest or most sophisticated Calculators. Includes the way to calculate using only a simple tour -function calculator: trigonometric COMPUTERS AND THE RADIO AMATEUR functions; hyperbolic functions: logarithms; square roots 66306P 528.00 and powers. For the radio operator who wants to know how computers function and how they can be used with other equipment. general SOLID STATE SHORT WAVE RECEIVERS YOUR ELECTRONIC CALCULATOR AND YOUR MONEY FOR BEGINNERS TELEMATIC SOCIETY BP54 $4.64 decimals. $4.32 102460P 517.50 Starts with a basic revision of percentages and 222B with mortgages, cars, insurance, fuel, construction of several solid-state shortwave An extensive update of 'The Wired Society', this book then deals Design and tax etc. There's a section on investment and the giving high level of performance yet utilising demonstrates how developments in telecommunications shopping, receivers last section deals with the calculator in a small business. relatively few inexpensive components. See also 226. will affect the way we Ilve. -ORDER FORM 1 Send to ETI Book Sales, 140 Joynton Ave, Waterloo NSW 2017. Allow 4-5 weeks for delivery. Post & Handling $1 per book. Effective until July 31, 1983 Please supply: BOOK TITLE BOOK NO. WV TOTAL PRICE Post and handling I enclose TOTAL S Name: Please debit my Bankcard Expiry Date American Express Card Address: Number Postcode Signature J 152 - July 1983 ETI WANTED TO BUY: Standard mini -floppy drive, Ep- MINI -MART son printer. B.J. Wight (08)356-0817. Where readers can advertise FOR SALE: DIGITAL CASSETTE drives (3), 720K/ - cassette, 24 Kbaud. Fast fwd/bwd file search, load a 15K file in 5 s. Full documentation including pro- For Sale/Wanted/Swap/Join ven Interface. S120 each. (03)339-5604 bh or (03)379-4438 ah. We'll publish up to 24 words (maximum) totally free Conditions: Name and address plus phone of charge for you, your club or your association. Copy number (if required) must be included within the 24 MICROBEE OWNERS: The Sydney MicroBee Us- must be with us by the 1st of the month preceding the words. Reasonable abbreviations, such as 25 W RMS ers' Group (formerly Northside) is your most con- month of issue. Please - please - print or type or 240 Vac, count as one word. Adverts must relate to centrated source of information, with monthly adverts clearly, otherwise it may not turn out as you electronics, audio, communications, computing etc - meetings and newsletters. Phone Tony Williams intended! Every effort will be made to publish all general adverts cannot be accepted. (02)909-3951 or Colin Tringham (02)92-6408 ah. adverts received; however, no responsibility for so Send your advert to: doing is accepted or implied. Private adverts only will FOR SALE: MICROBEE 'Guess the Number' pro- be ETI Mini -Mart, accepted. We reserve the right to refuse adverts gram. Three levels of play. Tape 55. T. Knowler, 37 considered unsuitable. 140 Joynton Ave, Waterloo NSW 2017. Bingley Crescent, Fraser ACT 2615. ACT VIC-20 BIMONTHLY NEWSLETTER: Many in- teresting articles and programs. June issue S1.50. AUDIO Bimonthly S8 per year. Write to Chris Groenhout, MISCELLANEOUS 25 Kerferd St, Watson ACT 2602. SELL: ZX 80/81, 4/8K ROM, FOR SALE: STAX SRA-12S full preamplifier FOR SALE: DISCO STROBE, variable flash rate, 16K RAM. Complete with printer, tape includes high voltage amp, drives electrostatic working 100%. Hardly used, great for parties, recorder, mags, etc. Perfect run- 520. ning order. headphones directly. No longer made but critical (02)451-1620. Half price 5399. (08)384-4208 spares included. Mint condition. Retailed 51100, sell 5550 ono. (07)229-3631. SELL: ADDO tape punch, reader, spare punch SELL: TI RS232 interface, 5180. Tandy Mk. VII mechanism, 10 rolls tape, 580. Model 15 TTY, 535. printer, 5350. SD Z80 starter kit, 5250. B.J. Wight (08)356-0817. FOR SALE: DAVID HAFLER DH200 amplifier, Paul Fuller, 24 Penman St, New Lambton NSW 100 WRMS/ch, dc 150 kHz. Superb sounding 2305. (049)57-2409 weekends. - FOR SALE: ZX81, 1K, leads, manual, 1.2 A power power amp. Mint condition, 5620. (02)896-2975. FOR SALE: UNUSED parts, 74181N, DM74126N, supply, numerous programs, constructional arti- DEC7476, FNo500, NM74C175, DM74153N, cles (add-on memory, etc). 5170 ono. F. Los, 13 FOR SALE: EQUALISER/REALTIME spectrum MC14012B, DM74150N, DM7489N, DM7476N, Kroombit St, Dulwich Hill NSW 2203. analyser. Fast/slow LED grid, pink noise, cali- F7442APC, MC14001B, SN 7483 AJ, DM7474N, brated microphone, multi -purpose line/level pro- LM325N, 7622, HEF4081P, DM7486N, MC14078B, SELL: MICROACE (ZX80 equivalent). 2K adaptor, cessor. Audio control C-101. New 5800, sell S455. 7705, DM7448N. (08)295-3181. leads, manual, one tape, three books, 5170 ono. G. (02)620-1203. Clarke, 33 May St, Inverell NSW 2360. WANTED: TELONIC sweep generators, 1006- WANTED: ELCASSETTES and In player any 1011-1030, state price. Will consider others with SELL: CENTRONICS 737 printer. 30 cps upper/ condition. Also four track tape deck. Lachlan same coverage. Hickman, PO Box 74, Hamilton lower case, three font styles, friction/tractor feed. MacDonald, P.O. Box 218E, East Vic. Ballarat, NSW 2303. (049)48-5553. With manual, carry case and leads, 5800. J. 3350. (053)41-3658. Thomas (02)546-4321. AUDIORAMA RECORDING CLUB is the club for FOR SALE: SYSTEM -80 computer, 16K RAM, you. We seek the enthusiast and the beginner. joystick interface, over 5400 worth of software, Many services available. For details contact COMPUTERS manuals, books, etc. Good condition. Software G. Harris, 7 Coleman Ave, NSW Homebush 2140. recorded on 50 tapes. 5250. Tasmania (002)72-6412. FOR SALE: LED PEAK record/output level display FOR SALE: ETI-660 3K colour, modulator. Fibre- monitor. Calibration/reference level sets, profes- glass case, hex keypad, power supply, loud- FOR SALE: ETI-660 microcomputer, ETI-760 mod- sional features (invaluable Revox A77 owners) speaker, step -repeat function plus many ulator, 3K RAM, colour option. Constructional, Audio Technology. Model 5108, sell 5135. (02)620- programs on cassette, 5165. (02)542-1365 programming and software articles, also most of 1203 published software on tape. 5140. Peter (02)708- OSI SUPERBOARD II: Complete with 8K RAM, 2014. power supply, monitor, FOR SALE: HANIMEX 4400 SL synchrocorder. instructions and two BASIC games books. Lot Cassette recorder with inbuilt slide projector con- 5350. Dane Howe SELL: TARBELL SD/DD floppy disk controller troller. As new condition, with accessories, (03)350-1646. board, 5300. Godbout RAM 16 64K, 8/16 bit instructions, S190. Terry Day (02)73-0433 ext. 440. memory board, 5650. A. Cummins, 17 Torrington VOICE SYNTHESISER: Built and tested. Based on Rd, Maroubra NSW 2035. (02)349-3684. EA Compuvoice. Phoneme programmable, in- cludes speaker, data, plugpack. Suits parallel SIEMENS 100 TELEPRINTER: A limited number of Centronics port: -80, COMMUNICATIONS System Super -80 etc. 5250. operational units are available. The models come Greg (02)644-3491 ah. with or without a keyboard and/or tape punch or reader. They can be picked up or delivered for FOR SALE: HEWLETT-PACKARD HP -85 desktop vehicle running costs, meet you halfway, literally. WANTED: SINGLESIDEBAND receiver, 12 V, computer, 32K. Compact, built-in VDU, random- From 565. Frank Rees, 27 King St, Boort Vic 3537. crystal -locked, loudspeaker, covering channels access minicartridge and thermal printer. BASIC, used on small ships, broadcasts by Brisbane Visicalc, games, tapes, paper. As new, 52500. SPARE PARTS: Most parts except motors avail- radio. I require a circuit to be designed and a set to (03)80-5635 ah. able, to be sold as subassemblies, e.g: any part for be made. Contact H. Fraser, PO Box 158, type basket (character font) can be obtained by Bunderim Old 4556, MODEM CLUB for System-80 and TRS-80 comput- buying whole assembly. I have some arms (badly ers. (03)397-6972 for verbal enrolment. bent) with characters Intact for those capable of FOR SALE: ARC 3-channel/3-servo remote con- changing ends. All parts from 52 to 515. Parts trol system, never been used, 5100. Amphenol FOR SALE: DBASE II including ZIP and TUTOR. available include tape punch and reader assemb- 10 -channel AM transceiver, 550. Scott Relational database management system and re- lies complete, each 55. Despatch post or rail. (068)47-2532. port generator for Osborne 1. Total value over Frank Rees, 27 King St, Boort Vic 3537. 5900. Will sell 5400. Vic (02)747-4218. FOR SALE: SX200 scanner, IC290A. All mode 2 SUPPOR r AVAILABLE: As a keen hobbyist I'll metres, Daiwa VHF -UHF SWR. All as new. FM321 FOR SALE: DISK DRIVES for Apple. Two low - correspond with anyone needing assistance with 80 -channel UHF, 16 -element LPY. (047)54-2214, prof ile 250K drives. Brand new, never used, 5380 their hobby. Frank Rees, 27 King St, Boort Vic leave message. each. (03)339-5604 bh or (03)379-4438. 3537. ETI July 1983 - 153 ORCES Do not adjust reality . there's a fault in your fantasy. * ~mg b Ceti-. ` .4.S" J i FOR THOSE FANS of the computer and the same benign, familiar-with -that microseconds," said the microprocessor the ubiquitous computer game who fashion ever again. to the buss driver. have braved the queues and the crowds Sidestepping the kill -or -be -killed "Would you like a POKE?" said the data to see the movie (and I use that term basis of the Tron fantasy and drifting off buffer to the screen RAM. loosely) `Tron', ponder a moment what in a direction more reminiscent of "Seal it with a handshake," said the went on on 'the inside'. There was the Woody Allen or Mel Brooks, just let your I/O port to the printer. hero, whizzing around inside the cir- thoughts wander along a more whimsi- "No PEEKing," said the protected cuits, through gates, over flop -flops, cal or satirical path. RAM to the address buss. down the buss etc. in his own little 'car- Imagine the sort of conversations you "PEEK before you POKE, or you'll rier'. Pursuing our micro hero were might hear if you could plug in to the risk corrupting your data," said the OS numerous 'baddies', but along the way circuits inside a computer or computer to the input. were some friendly 'components'. It was game and 'have all those 'instructions' Perhaps some of you Dregs fans might all a deadly serious fantasy in the best decoded into speech. Your digito- come up with some 'conversations' in cops -and -robbers, cowboys -versus - doodling Dregs writer did this exercise the same vein? We'll publish the 'best' of Indians, good -versus -evil traditions. recently while doing a dump to the office them as they come along - no prizes, If you haven't seen Tron, dig it out in output port and found these 'conversa- just a chance to join in the fun. Write to: some suburban cinema or from a vid- tions' drifting through his memory "Conversations on the buss", E'I'1 eotape library and see it. You'll never banks: Magazine, P.O. Box 21, Waterloo NSW view a computer or computer game in "I haven't had a good interruption in 2017. 154 - July 1983 ETI e SONY. THE ONE AND ONLY The Sony CDP101 The magic of digital audio becomes a magnificent reality. Digital Audio is a revolution. The greatest automatic music sensor dual function digital advance in home music reproduction since the readout of playtime audible fast forward and gramophone reverse 10 function wireless remote control. record. As you'd Compact Discs Last Forever expect, Sony is the Just 12 leader of this cms in diameter, the Compact Disc plays up to 60 revolution with its minutes of music. It's protected from magnificent scratches, dust and finger prints by a plastic coating; and CDP-101 player because the pick-up is a laser beam, deterioration is that offers you non-existent. Reproduction remains perfect virtually original studio forever. Hundreds of master quality at titles will be available with many r more to home. follow from major companies such as CBS For the CDP-101 Specifications technically minded, the specifications Frequency Range 5Hz-20kHz ± 0.5dB read more Dynamic Range more than 90d B convincingly than S/N more than 90d B any superlatives flat frequency Channel Separation more than 90d B (at 1kHz) response over the entire audible range dynamic Harmonic Distortion less than 0.004% (at 1kHz) range and signal to noise ratio over 90dB perfect Wow and Flutter immeasurable channel separation immeasurable wow and flutter negligible distortion. Sony's CDP-101 uses an optical laser pick-up (incorporating three micro processors), it is easier to SONY use than a conventional turntable and connects see easily to your existing 7 system. Other features r include fully automatic linear skate iiiiii front disc loading -1-1..3r w I Contact Sony for the name of your nearest dealer. Sydney (02) 2660655, Adelaide and N.T. (08) 2122877, Brisbane (07) 446554, Perth (09) Melbourne (03) 3238686, 4193133, Launceston (003) 443078, Wollongong (042) 715777. AÚ00378 Every car, like a new born baby, starts off with a beautiful body. But the trick is keeping it that way, so the good news is Wash-n-Wox and Glo Wash from The Kitten System. Now you can buy a beautiful body off the shelf, and keep your car in showroom condition. Glo Wash is made especially for cleaning your valuable investment. ee 41 :ooidetergent and water may only41110. Whereas ordinary clean the surface, Glo-Wash removes stubborn road grime that would otherwise become ingrained and cause your paintwork to rapidly deteriorate. And if you want to give your car extra special protection, The Kitten System brings you Wash -n -Wax. Wash -n-Wax is the blend of specially developed high quality cleaning agents and waxes that protects as it waxes your cor's body. But the beauty of both Wash -n -Wax and Glo Wash is their wash-on/hose-off simplicity; there's no need to chamois anymore. And a good looking body won't cost you an arm and a leg: a bottle of Wash -n -Wax or Glo-Wash will wash the average carat least 17 times. So for a good looking body, use Glo Wash or Wash -n -Wax from The Kitten System at least once a week. I(IT ill I(ITTENe 511 17times. wax as it .deans. 00 f01 cars.Adds washes Spec '1 shame Ecorwn,Y pack 500m1 500m1 EM, KIW311/1 THE I(IT1'EI! THE CREAM OF CAR CARE