Telex PROCOM2 User manual

PROCOM 2
AIRCRAFT INTERCOM
USER INSTRUCTIONS
INSTALLATION
(Referto the SystemConfigurationdrawing)
Plugthe ProCom2 (PC2) intothe aircraftradioor audio paneljacks.
NOTE: Ifthe aircraft radio does not providesidetone, the pilotwillnot be ableto hear himself or herself
inthe headsetduringaircraft-to-towertransmissions.
Plugpilotandcopilot (or passenger) headphone and microphoneplugsintothe appropriatejacks onthe top panel
of the PC 2.
PushTo Talk
(PlT) SwltchNotes
1. If the aircraft hasabuilt-inpilotyoke switch, it is not necessaryto usethe pilot PTTjack onthe PC
2.
However, it isimportantthat the aircraft radioor audio panelmicrophonejack tip be wired so that
keyingthetransmitterwith the built-inyoke switchwill also groundthe jack tip. This signal isthen
sensedby the PC
2 (viathe Ytable microphone/PTTplug)to cause properoperationof the intercom
duringtransmission.
2. If the aircraft has abuilt-incopilot yoke switch, it should not
be used. lf copilot PTTcapability is
desired,use a portable PTT switchpluggedintothe copilot PTT switchjack onthe PC 2.
3. If poltable
PTT switches are used, do not plugmicrophonesintothem, as the PTTswitches willhave
to
be pressedtotalkoverthe intercom. Plugmicrophonesintothe PC 2 microphonejacks only.
Connectanextemalmsicsource tothe rearpanelMUSIC INPUTjack of the PC 2usinga 0.140-inch (3.6 mm)
stereo "miniplug."
Use one of two methodsto providepowerto the PC 2 intercom:
Forinternalpoweroperation, installa9-~0ltbatteryinthe side compartmentof the PC 2.
Forexternalpower operation, use an optional aircraftcigarettelightercable (TelexCatalogNumber96513-
000). Itisrecommendedthat you use a 100 mA (fast blo)fuse inthe externalpower source. Plugthe cable
intothe aircraftcigarette lighterand intothe AUX POWER jack onthe rearpanelof the PC 2.
CAUTION
Ensurethat the polarityof the externalpower isas shown inthe figure
below. lrrpmperconnectionmay result indamageto the PC 2.
AUX POWER
12-28VDC
@ 100MA
O Copyright Telex Communicalions. Inc. All tights resewed.
TELEX,

AIRCRAFT
CIGARETTE AIRCRAFT RADIO MUSIC
LIGHTER OR AUDIO PANEL SOURCE
n m n
opTloNA$ PHOY ry
POWER Y-CABLE
CABLE
, --$/ -,
%%-*
nnra Q 4 go&
PILOT HEADSET COPILOT HEADSET
/-7 PC 2 REAR VIEW n
u
PORTABLE
PILOTPTT
SWITCH PORTABLE
PC
2 TOP VIEW COPILOT
PTT SWITCH
SystemConfiguration
OPERATION
Leavethe aircraft radioandmusicsourceoff, and set the PC 2 lockingpower switchtothe ONpositionby pulling
outwardonthe switchandpushing
it upward.
TumtheSQ (squelch)controlfully clockwise.
NOTE: This is nota "hot mic"position, but it isthe positionwhere minimumvoice levelwill be required
to activatethe intercom.
While talking into pilotandcopilot microphones,adjust the PILOTVOL andCOPILOTVOL (headphonevolume)
controlsasdesired.
Tum onthe music source. If the musicsource has avolume control, adjust it for the desired listeninglevelinthe
headohones. If the music source does not have avolume control. the levelmav be adiusted usinathe MUSIC
trimnier onthe rear panelof the PC
2.
Talk into a microphoneand notethe amount of music mutingduringtalk. If more or less muting isdesired, adjust
the MUSIC MUTEtrimmeronthe rearpanelof the PC
2.
Turn onthe aircraft radio, and adjustthe cabinspeakervolumeto an acceptable listeninglevel (thiswill establish
a nominal inputvolume levelforthe intercom). Notethe radiovolume when listeningwiththe headphones,and

compare it tothe volume levelwhentalkingon the intercom. Ifthere isa
differenceinlevels, adjustthe equalizationtrimmer (labeledRADIO)onthe
rearpanelof the PC 2 untilthe radiilevelisthe same asthe intercomlevel.
Set the powerswitchto OFF (FAILSAFE)whenthe intercomisnot inuseto
consewe batterypower. Inth'is positionthe pilotphonesareconnected
directlytothe radio (the pilot microphonesignalisalways connectedto the
radioexceptwhencopilotistransmitting).
RearPanelTrimmer Controls
AUTOMATIC SQUELCHOPERATION
The PC 2containsanautomatic squelchcircuitwhichmakesmost manual
squelch adjustments unnecessary. This circuituses a built-inmicrophone
to monitorthe noiselevelinthe aircraft. The microohoneis locatedonthe
top panelof the PC2 nexttothe pilotMICand
PHONE jacks. For proper
operation, do notobstructthe microphone.
Inmost casesthe manualsquelch controlshouldbeleft inthe extreme
clockwise ~osition.andthe automatic sauelchcircuitwillcomoensatefor
mostchan'gesinambient noiselevel; hdwever, ifthe ambieninoise level
duringoperationof the aircraftbecomestoo loud and causes undesirable
intercomactivation,rotatethe squelchcontrol slightlycounterclockwiseuntil
the intercomaudio tums off. The intercomshould reactivatewhen speaking
intoeithermicrophone. SquelchCircuit
Microphone
ACCESSORY INFORMATION
OptionalAircraft PowerCable ............................... CatalogNo. 96513-000
2-Foot (0.6 m), withCigaretteLighter Plug
ModelPT-300 Push-To-TalkSwitch
.......................... CatalogNo.63966-000