NEW *** High Dynamic Range 70CM Transverter Kit ***
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Down East Microwave Inc. 954 Route 519Frenchtown, NJ 08825 Phone: 908-996-3584 (Voice 908-996-3702(Fax NEW*** High DynamicRange 70CM Transverter Kit *** NEW DEMPart Number 432-28 Operational Overuiew The New DEM 432-28 is a 70cm to 28 MIIZ transverterwith a list of new featuresthat allow it to be more versatile in operation.It will operatewith all 28 MHz. transceiverswith transverterports andwith a simple option, it will be compatible with any 28 MIIz. transceiver with l0 Watts or lessoulput power. The 432-28has a maximumlinear ouq)utpower of 30 watts and can be limited with an adjustableattenuator to preset the outputpower ifyou choseto use an additionalpower amplifier. The most noticeableinprovement in the transverteris in the receivesection. Additional filtering, (two separate helical filters) a high biasedGaAs-FET prcamplifier coupledwith the edsting high level mixer (+17 dBm Local Osci.llator),provide a sensitive,yet over-loadprooffront endwith superiorout ofband rejection. This is the bestreceive converteron the markettoday! The 432-28has a built in tranffiit / receiverelay but provisionshave been made to allow separatingthe tansmit and receiveports to add a high power amplifier or to interfacethe tansverters additionalreceive filtering with a extemalor mast-mountedpreamplifier. Additional optionshave been included to customtune youxreceive gain requhementsto obtain the bestperforrnance (sensitivity and IMD) possible. Dual oscillatorsaxe provided for operationin the satellite portion ofthe band.Keying options for +l to + 15VDC, PTT-H or a closureto grormd, PTT-L, havebeen provided. Auxiliary relay contactsto control extemalhansdt and receive firnctionsare available.A commonIF option that will operateat drive levelsbetween -20dBm and 10 watts may be purchasedseparately. All IF connectionsare BNC comectors.The control, power, and auxiliary connectionsare RCA 'N' jacks,and the 70crnconnectors are Type (2 supplied).The 432-28 is housedina8.7" x5.7" x2.2" aluninumdie cast enclosurewith an external8 lz" x 4" x3A" heat sink to provide cool operationunder any conditio[ \ DEM 432-28Operating Spec ifications OperatingVoltage 11.0- 16.5VDC. 13.8nominal Current Drain 6 ampsmaximum on Transmit, 600 milliamps on Receive Output Power (Standard) Maximum 30 W linear. Output has25 dB of adjustablerange. Minimum I mW (0dBm) for l0 watts output power. OutputPower (Optional) The sameoutput power can be achieved,with -20 dBm or up to 10 watts of drive dependingon the option used ReceiveNoise Figure and gain 1.0 dB maximum, 0.8 dB nominal, @ 17 dB conversiongain for best receiveintermod performance.Other gain options are availablethat will affect systemnoise figures, and IMD performance. Assembly Options Common IF input/output option I - l0 Watt IF drive option External TR switching control -20 dBm IF drive option SeparateTransmit and Receiveports External preamplifier option +1 to 15 V TTL or PTT ground keying Factory alignment available on all kits I File 432-28_C.doc * DEv, 4J2-28Revision c t2ttstgSpage 1 Down EastMicrowave lnc. gs4 Route s1g, FrenchtownNJ 0ss25 -6 + Phone:908-996-3584 (Volce)908-996-3702 DEMI (Fox)http:/Aruww.downeostmtcrowwe,com DEMI oo TF 3.8VDC XMIT RECEIVE PTT- H L AUX RX Connect Wur transceiver to the transverter: Interfacingthe transverterto the transceiveris easy. lf your transceiverrequires a DEM TlB, follow thoseinstructjons for interfacing.If the transverterwas configuredfor direct connectionto your transceiver,follow the stepslisted below. 1. Open lid of transverterby removing6 screws. 2. Dependingon the makeand modelof yourtransceiver, it may or may not be necessaryto enablethe transverterports. Followwhatever instructions you have,inyour transceiver'soperation manual to enabletransverter operation. lf it requiresa specialconnector or cableassembiy, it shouldbe made now or contactDown EastMicrowave for assistance. 3. Connectall lF cables. Both receiveand transmitare BNC connectionson the transverter.Use qood qualitycoax cableto connectthe 28 MHz. transverterports from your transceiverto the TXIFa;d RXIFconnectors on the transverter. 4. Connectthe Pushto Talk line out of your transceiverto the transverter.lt is labeledpTT- H or pTT-L on the transverterand usesa RCAconnector. The correctkeying type is alreadyconfigured for your transceiver. 5. Connectthe 70cm antennasystem or a dummy load with a power meterto the transverter.lf one of 'Antenna" the "N" connectorsis labeled thenthe internaltransfer relay in the transverteris installed. Bothtransmit and receivefunctions will be providedthrough this connector. lf the ,,N,,connectors are labeled"Transmit" and "Receive",the internaltransfer relay has been bypassedand the separate portswill providethe labeledfunctions. 6. Connectthe DC power to the transverter.lt usesa RCAtype connector. 13.8 volts is optimum but the transverterwill operatenormally from 12 to 15 volre. 7. Presetthe TXIFand RXIFgain controls. Turn the TXIFfully counter-clockwise(maximum attenuation) andthe RXIFfully clockwise( minimum attenuation). 8. Poweryour transceiver on and leaveit in the Receivemode on 28.100MHz. 9. Applypower to the transverterand turn on the powerswitch. The powerLED should light and the transmitLED should nol Setthe localoscillator switch to 432MHz. 10.Adjust the RXIFgain control counter-clockwiseuntil a slightnoise increase is heard in the transceiver or just a slightmovement in the "S" meteris detected. Powerthe transverteron and off to verifythe change.The RXIFgain may be increasedbeyond this poinq but it will startto degradethe dynamic rangeof your transceiver.Find a signalon the band or usea signalgenerator to determinecorrect lBuil|a32-2B.doc Rev.A 11lOBlA1 Down East Microwave fnc. 954 Route 519Frenchtown, NJ 0882'5 Phone: 908-996-3584(Voice, 908-996-3702(Fax PrintedCircuit Assembly Notes: Your kit is provided with easyto read componentplacement diagrans that showthe componentplacement and the referencedesignators that correspondto the provided componentlist (Bag 1 - Bag 4). Each side ofthe printed ctcuit board (PCB) is also shownto eliminatemirror imageassembly erlors. The top andbottom side assemblyoperation should aluays begin by aligning the PCB outline with the out line of the componentplacement diagams. Use the notcheson the longer sidesofthe PCB board as a key. You may also usethe printed lettering on the top side ofthe PCB board for a indicator. You will also notice on the assemblydiagram that thereare circles, doublecircles, and ')(" shown. Theseare shownto provide locating help when installing components.Components are mounted in the singleholes. Double Circles are Mounting Holes and Holes with 3'X" are for Wire installation only! Assenbly Tips: Solderingsurface mounted active components (transistors etc.): o The DOTS on the MMICs (ICl - IC4, IC6 - IC8) determinetheir orientationand mustbe observedand positioned correctly prior to soldering.The GaAsFET(Q6) andBipolar (Q5) orientationis determinedby their lead formation,either longer or anglecut. The GaAsFET(Q6) anglecut lead or dot is the Gate side vrhich corresponds to the assemblydiagram (See Figure 1B). The long lead on the Bipolar (Q5) is the collector and conespondsto the assemblydiagram (See Figure lA). Leadson all active surfacemounted components should be somewhatflat againstthe mountingsurface, ifthey arenot, a tool suchas a small bladedscrew driver can be usedto flatten them. (SeeFigure 2). o Align the componentin placebased on the diagram. o While holding the componentin place,solder one leadto hold the componentin place and observethe alignment of all leads. o If the alignmentis acceptable,solder the rernainingleads. You needenough solder to cover the lead andmormting swface for the entire lead length.Additional amountsresults in a smallersolder roll! (SeeFigure 2 shadedareas) Collector Long Lcad Q5 Figure 1A Q6 Figure 18 L€ads Itat to trace,4plm Solder shown in sbaded arcas Sonr 'l* backisU( Solder full length of lead,4 places vI FCtsTrace Typical side view offour leaded surface mounted device, lead bending close to body Figure 2 I File 432-28C.doc * DEv^ 4t2-28 Revisionc tzttstggp,.ge 2 Down East Microwuve Inc. 954 Route 519Frenclttown, ^{J 08825 Phone: 908-996-3584(Voicd 908-996-3702(Fax Solderingsurface mounted passive components (chip resistors/ capacitors): . Determinethe componentmounting position basedon the assemblydiagram. Without the componentin place, heatone side of the mounting areaand flow a small amount of solderon it. Placethe componentin the correct posilion per the assemblydiagram, it should now haveone end over the previouslymelted solder. Holding the componentin placewitl tweezersor other solderingaid, heat the end with the previouslymelted solderand allow it to flow into the solder,once solidified, removeholding tool. Now heat and flow the solderto the other side of the componentand your done! Solderingleaded components (resistors, capacitors, diodes, etc.): Dependingon your availabletools, you can solderyour transverter'scomponents from either the top or bottom of the PCB. It is suggestedfor the horneassembler to usea methodthat is comfortable.A simple holding vise can be utilized 'dropped to allow the componentsto be in' from the top side and solderedon this side withont flipping over the assembly.As an altematemethod, you can insert one componentat a time in the correct moundng location and gently push down to the circuit board, while holding the component,flip over the circuit board and bend the leadsover in oppositedirection to hold the compon€ntin place.Although