Apache Labs ANDROMEDA ANAN-7000DLE MKII - 8 Connecting Accessories; 8.1 Linear Amplifier; 8.1.1 PTT Out; 8.1.2 ALC

ANDROMEDAManual Page41of56
8 ConnectingAccessories
8.1 LinearAmplifier
8.1.1 PTTOut
MostmodernLinearAmplifiers haveaconnectionforkeyingtheamplifier.Theradioincl udesaback
panelRCAconnectionforthispurpose.
ThePTTOutfeatureisbestusedtoswitch25vdcand1A.Exceedingthesevaluesmaydamagethe
PTTOUTPUTcircuit.
HowtotestyourPTTLinearAmplifiercircuit
BEFOREconnectingyourApacheTransceiver:
1. PoweryourLinear,connectthecontrolcabletoyourlinearbutdonotconnecttheother
endtoyourApacheTransceiver.
2. UsingaDC Voltmeter,measurethevoltagebetweenthecenterpinandtheouter
connectionofthecable.Thismustbeless
than25vdc.
3. ConnectaDCAmmeterbetweenthecenterpinandtheexciterconnectionofthecable.This
shouldACTIVATEtheLinearAmplifierandgiveyouaclearmeasurementofthecurrent
requirements.TheANDROMEDAPTTcircuitshouldnotdrawmorethan1A.
4. Ifeitherofthesevaluesare
outoftherequiredrange,thenuseanexternalkeyinginterface.
TherearemanykeyinginterfacesavailablefrommanysourcessuchasMFJ,Elecraft,DX
Engineering.
Important:ConnectingaLinearAmplifierthatdoesnotmeettheabovevoltageandcurrent
requirementsislikelytocausedamagetotheApacheTransceiver
linearswitchingtransistorand
extremecases,seriousdamagetootherparts.Damagetotheradiocausedinthismannerisnot
coveredbyWarranty.
LinearAmplifierKeyingISOLATIONadapters
http://www.dxengineering.com/search /product‐line/kd9sv‐products‐sv‐kr‐keying‐relays
http://www.ameritron.com/Product.php?productid=ARB‐704
http://www.sultantronics.com/product.html
8.1.2 ALC
ANDROMEDAdoesnotofferALCcontrolforanexternalamplifier.Itisimportanttosetthedrive
levelsothattheamplifierisnotdrivenintosaturation.Driveshowsa%ofANDROMEDAfullpower;
settingthePAgaininthesetupformisthebestwaytoachievethis.
8.1.3 OpenCollectorBCDkeying
AutomaticBandSelectioncanbeaccomplishedusingtheOpenCollectorOutputsavailableonthe
OCDB‐9Fconnectoronthebackpanel.
ThisisanexampleshowshowtoprepareOpenCollectorOutputsforBCD[binarycodeddecimal]for
controlofexternaldevices[suchasbandinformationforaHerculesLinear
Amplifier].