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7 No. f 68 216 TRANSISTOR ,'\ ) CIRCUITS MAI{UAI, { No. 4 by CLIVB SINCLAIR C,lTTCLI'IS I!,\I] iiis] R,UCTXOiVS F]S}I BLIilLDING "frvo L tran.sistor supr:rilet. ). Ii!-Fi tape acri picii-up pre-arnp. l. lli-lji 3+irtt unrpli!iir- l. triiii;rture ma:.;\ D.:\,.cr packs. 5. 5 ficis to 2 mc/s sign:il injecfor. 6. Scnsitive subrtiniaiure lcudsgre:rker.racllo, 7" Single t;rrasistor reg;r_.ner*tivereceiver. .i5-rrntf $, puirlic arirlrer;sanip!ifiei. -[ransirlor 9, voltmrrer. Ii.i" Sirnple earpiece r.eflex receir.er. ; i. Simp)i..transnritter. BERNARDS RADIO MANUALS r TRANSISTOR CIRCUITS MANUAL No. 4 by CLIVE SINCLAIR LONDON BERNARDS (publishers)LT.D BERNARDSRADrO MANUALS No. 168 GeNrn.,rr-Eorron : CLIVE SINCLAIR First publishedDecember 1960 Repr.in,tedNovember, 1964 ReprintedJanuary, 1966 ReprintedMay, 1967 On Page II TAPE AND PICK-UP PRE..{N,PLIFIER In third paragraph of text, third line should read : 8 volts, not 2 volts. On Page 12, Fig. 3 The 330K rcsistor betweenthe beseof Tr. I arrd the emitter of Tr_I should bc of pre_settype. o 1e60. Printed by V. Cooper parrners - & Ltd. Flitcroft Street, W.C.2. I'or Bernards(publishers) Ltd., The Grampians,western Gate, w.6. l* '- l CONTENTS Page Introduction 5 Noteson useof OCl69 transistor :'. 6 l. Two TransistorSuperhet.., 8 . ) I'Ii-Fi Tape and Pick-Up Pre-amplifier... 11 3. Hi-Fi 3-wattAmplifier 15 4, Miniature Mains PowerPacks ... l8 5. 5 Kc/s to 2 mc/s SignalInjector... 2L 6, SensitiveSubminiature Loudspeaker Radio 23 " 7. The " Mighty Atom SingleTransistor Receiver t{ 8. l5-Watt Public AddressAmplifier 28 9. TransistorVoltmeter 29 10. Simple EarpieceReflex Receiver... 34 11. SimpleTransmitter 39 Addressesof Manufacturers 40 LIST OF ILLUSTRATIONS Fig. No. Page l. Physicaldetails of the OC169 .,. 7 2, Two TransistorSuperhet .,. 9 3, Pre"amplifierfor tapeor magreticpick-up 12 4. Responsecun'es for circuitin Fig. 3 13 5. Bassboost circuit lor Fig. 3 14 6. Circuitdiagran, of the 3-u,attamplifier 16 7. Miniaturemains pouer sr"rpplycircuits .,. 19 8. 5 Kcis to 2 nrclssignal injcctor ... 22 9. Circuitfor 3 transistorreceiver ... 24 10. " Mighty Atom " transistorreceiver 26 11. Additionof longwave coil to I'ig. l0 ... 27 12. First 3 stagesof publicaddress amplifier 30 13. Driverand outputstages.,. 31 14. High input resistancevoltmeter ,.. 32 15. Simpleearpiece reflex receiver .,. 36 16. I-ayout for simplereflex receiver... 37 17. Simpletransmitter circuit... 38 INTRODUCTION The , rapidity with which new componentshave appearedon lhe nome constructor-marketin recent months has betn pleasantlv surprising. It seemsthat,manufacturers are UeginningiJ i;i;'; new interest in this outlet for their products. - In the field of transistorsa new drift type hasbeen made available, the OCl69. This unit has the samepara-eters as the OCl70 bui ry]19.fo1 only l8/0d. which makes if far less of a luxury articf.. As rrs cnaracterutlcs are ertremely good it may be used in a great many a_pplicationsthat might suip-risesomeone unfamiliar iii'h them. Many of ,thecircuits in thij book make use of the OCl69 and a chapter o! the transistor itself is also included for those of )ou who hke to know exactlyrvhat sort of animal you are deating with. some of it is rather technical but a rittle uri"fttr..w o*i no one any harm. ., I have.bee.nreceiving a great many letters recentlyconcernine rne clrcurtsthat have appearedin the transistorcircuits manualsl-ind Many of them contain some query about one of tire clriuits llre.se.I3p .only.to-o pleased to-aniwer althoughsometimes I g;; ; Iittle behindwith them. However,I shouldliie to hearfrom irori of you concerningthe type of equipmentyori are most ilile;i;a;; so perhapsyou could sendme a postcard. From the letters I have so jt lTj*:d far appears thaf receivers are the ,"o.i-;;p;ia; proJects(to borrow an excellent Americanism) and thi imall-f-[i, pocket sets^wjth.loudspeakerare the -ort poprilu. .f att. nas oeenreflected ln thls tssueand new setsare beingdesigned and tested at the moment. However, there may be othei ttp6 ;a;;i; which have not yet appearedbul which w6uld be welio^med. Transistors continue to replace valves in their traditional applicationsand the next take oler bid is likely to take placei,r the high fidelity field. power transistors are now available with performanceswhich are in no.way inferior to those ;a;;;".;bG valvesand thesemake it possibre-todesign quaiity "-piriii,i, *rtrt outpujs in_theregion of 20 watts. As a stirt iri this fieldihis manuil contains the circuit for a pre-amqiifier of extre;"t high F;i;;- ance and equipmentfor .usewiih this will appeir iri the future manuals-- whilst many still tend to think of th'e'transistorin terms ot portableusage it, has, in fact, many propertieswhich make it prercrabre to the valve in I?ICJI typesof domestiqequipment. ln tape recorders and other Hi-Fi equipment, where ttre 6rimination of mainshum is.of paramountimportince, tireii largescale adoption may not be far in the future. 'inaustsron. 6 C;ecurrs Maxr_lar,No, 4 In the books we have^publishedand in the n.ragazines,many cjrcrrits. have- -appear"a transistor ,.c"iu.., which simplicrt., {qa cornbine and low costrpith sufficientlytrign ferform"";; i;;iir;;; i ntcn,.l:ci .pplication. yuny superhefciriuit! n"u"- . jnto'th" ufio-;;il;i but ttrcschave never fallen ;G;;;i'ih; ;il j"iffi;;: tioned as they have used,.virtually withoiri 6xception,O, 8 transisiors. t;;;;;; This may have grvin ttri iverage fro* *nrti*toi-"*ir*o-ri"rv the erroneous idea that ar t-ransisioi r"pJi"t, c,ompricaicd,. iil expensive.anddifficult to uiiio. r.'iir'iii,i-tr*"."i.rr" theory this book contains -superhit "ii."itt'o-r ."riti".i"v lrp]i.itv which are suitabre?";ih"* ;^hl i'uu" buirt T.R.F. r.covered their first from their nrst itriitt ui-i,"a.ing it;;;i, ;;; dccidedri;at they require,ory.tt ing mo.J poi."t. the OC The arrivalof In,.)has made,v tur[ i.iufi";j;';;;i" in designing se^tsfor i;:, these colossalgain at tl.W. iriqGn.i.r-r.0.r".,' ti; "-G;;; of-siagrsrcquired foi any ei* p.if;;i;... By thc u'ay, . I am alwayiintereit"o n rr"u.inghow the circuitsin thesebooks are buirt andhow *.rr-'t"v r*it itiuu.iouipuii.itr,"^ countr),..Ma-ny.of you, I.know, thi;k up new- ways bf buildine ",d mod i tyi ng t he cqu i p.meni : l: ll i'*hi' describe'd. Sh"ii r,i v.""' U".ii,l""? tnese not write to,me giving_details p.*ipr, photograph "nitt.r'itiri,lr'v"uand ln.f"j,.;; or circuitciagrim. rrve the l.oncion or work in area ]'ou coitC cattln^i;;h ii ^y'ofn." which is in The Grampiansbuildiris -bein Streptreris ft";e. Should you have anythingrhat can usecl'inon" of tfr.iJGanuals you will, of coursc,be paid for it. NOTI]S ON THE USE OF THE OC169 TRANSISTOR The introduction of at a price, which l:ygtlt'ol rhat .the^OCl69 at 1g/0d is of eventLe^gg+s; ;ari, it Lrii6r" td;"1;;i!;;; OC45's,OC,44's or OCl70'snavlUii" ur.Jt.io.". The ocl69 is madebvrhe,attov oinuiion-tt'Lnique which achieves resultsfer superiorto ihe best'p;;;i6i; ;ri;; normatgermanium alloy.rnethoddby whichmeans rhe OC45and'OC4+;"-;;il;;il: Thc i ncreii ble i mDrove ment I " . rfoi,na,i."-u"ti"u.O' the oSJ69 f ;n;;;t"; may be reatised*ti*-;;;-;;;siders that its atoha cut-offfrcquencv is 100mc/s o. -o.". .o-piilO-rciJls jS for.rhe *itf,'"i,lv'dioii. ,i'ii,,o oC44 and thar irs po-wergain at ?50 'ifr"il" unila-teralisedcircuit compaiedwitfr ii ob. *it, is l'000,@0 tiribc+i timesas comparedwit-tr-5,000- td".. when usedas a mediumwave band frequenq,clqler ii--ufi piouit";;;: version.gainof 40 dB. comparedwith fri zd an OC44. os. "ut"i"iur" r-- Thehigh , frequencycJrt-offmakestheocl69 -it- ideal for usein F.M. recerverI.F. stageswhich,pormaJly operate Irequency to.l ,*lr.- ,,ii iirii eachstage will p,rovidei gain of ZS aS.--A;;#; appiicationthat is l-iketyto-^be reattv p-oputa'iiJin receivers raAio;;;i;;i operaringin ine zl mc/iuaiol-li hri, riiqid"y ;,h'; TnaNslstoR Ctncutrs ll{am;.lr- No { ALL DIMENS|ONS iN mm. L-9'l .r INTERLEAD SHIELD 'nox' | I AI.iD METAL CASE -c I r-rl mA I l',' \.il/ zsto o'-j*l |..-l zs*o os-l l-- | ffi-l s O +0'15-+1 l.- -!1.-o ou FIG. I. PHYSICAL DETAILS OF THE OC 169. OCl69 operatesexcellentll', particularly in superretcn- circuits.. The O-C169u'ill, in fact,-replaccthe N1ullardOC170 or the Edisrr,anXA131 in any circuit and may be usedin superregen' circuitsat frequenciesup tc about 90 mc/s' If you wish-to incorporatetl-ris transistor in circuitsof your orvn desigirhcrc are tirc lirriting val':rcsr"'hich lrust not be exceeded:- -VCB 20V. -lc 10mA' Ic 10mA' -Ic lmA. Pc (Tamb =-45'C) 50mW. The averagevalue cf common emiiter current gain-is,100. The charatteristics at an ambient temperaturc of 25oC are as follori's:- Normal \lininrum Maximum -ICBC (-VCB .- 6V) : l'5microamps <13 -lC -- _vLrJlIE,,.o ,f 50mu.A\ ._ ."..g0\/. --,20\r. __0 J I -rp sn,n,rA\ -vEB - _ 0.5\. 1 rc'" u" ) -r'cs ' 1 --rD I av - 15mu.A' '<50 1 le -. lmA | -\'cB , 1 -\'BE,,^- f 6v : 260n.r\/' >210nrv'<330mv' t;''" : iJ,,li r -vcB . 6\- I F* I lc Im.A,! - tsoe. <'lodll. l-f ' - lKcis] TRaxsrsronCrncurrs Ml^-utt No. 4 * Spot r.roisefigure measured rvith an input source irnpedance o[ 500 ohms.
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  • Reflex Radio Receivers 1924 Ocr.Pdf

    Reflex Radio Receivers 1924 Ocr.Pdf

    The "Experimenter's Library" 25c. Books Covering Every Branch of Radio Each book is written by a well-known author and con• tains 48 pages of valuable (••HM.TICAI. KflOlO information, fully illustrated. ftWf(U(Ni". r,fr.v Cover is in two colors, size 5/4 x7K inches. No. 1. Tips for the Radio Amateur Constructor. Hi No. 2. How to make Practical Radio No. 3. Receiving Set*. Radio Questions Answered. No. 4. Radio Frequency Amplification No. 5. Loud Talkers and How to Build Them. No. 6. IftAOlC QUESTION ALL ABOUT • How to Tune Your Radio Set. RADIO PARTS No. 7. 100 Radio Hook-ups. No. 8. All About Radio Parts. No. 9. History and Operation of the No. 10. Vacuum Tube. The Neutrodyne—All About It. No. 12. How to Locate Troubles in Your Radio Set. I © T«t(..^ Each 25c. Postpaid HOW TO TU«F. you ft f- flO.O SET THE CONSRAD COMPANY, inc. Selling Agents 233 FULTON STREET NEW YORK CITY THE EXPERIMENTER'S LIBRARY, No. 13 Reflex Radio eivers By P. E. EDELMAN TRADE Published by THE E. I. COMPANY 233 Fulton Street New York City Printed in the United State* of America Copyright by THE E. I. COMPANY 1924 All rights reserved, including: that of translation into foreign languages, including the Scandinavian INTRODUCTION. The growing popularity of reflex types of broadcast receivers is due to the efficient use of fewer vacuum tubes than equivalent outfits of different character re• quire. The reflex principle was proposed by Schloemilch and Von Bronk in their U.
  • No.17 Single-Transistor Reflex Radio Arrange the Blocks and Attach the Earphone and a Lead Wire (Used As an Antenna) As Shown in the Figure

    No.17 Single-Transistor Reflex Radio Arrange the Blocks and Attach the Earphone and a Lead Wire (Used As an Antenna) As Shown in the Figure

    in this project Blocks used Radio Circuits No.17 Single-transistor Reflex Radio Arrange the blocks and attach the earphone and a lead wire (used as an antenna) as shown in the figure. Then, turn on the main switch. Put the earphone in one of your ears. Turn the tuning knob back and forth bit by bit until you find a radio broadcast station that you can pick up. The transistor first amplifies high-frequency signals and then amplifies the low-frequency signals detected by the diode that have been returned to the transistor. A radio that works to amplify both high-frequency signals and low-frequency signals using the same single transistor, as described, is known as a “reflex radio.” * In blocks with lighter lines, current only flows along Block Layout Diagram the dark, solid lines. Circuit Schematic High frequency Voltage doubler detector Low frequency Circuit Mechanism As a basic outline, the transistor-based amplifier circuit formed using the 1-kΩ resistor and 1-MΩ resistor connected to the base and the 1-kΩ resistor and 4.7-kΩ resistor connected to the collector operates twice, once for high-frequency signals and once for low-frequency signals. First, the high-frequency signal current is received from the secondary coil of the tuning coil. The current is amplified by the transistor as it flows along the path indicated by the dotted line in the figure at right. The 100-pF capacitor passes only high-frequency signals. As shown, the high-frequency signals flow along the path indicated by the dotted line to enter the voltage doubler detector circuit (described below).