Racal Instruments AN/TRC-207, Operation And Maintenance Instructions, Page: 46 / 102

TO 31R2-2TRC207-1
4-12
j. Set the SENS control fully clockwise.
k. Place the bi-directional repeater MODE SELECT switch (6, Figure 4-1) in the TUNE B position.
l. Adjust the diplexer XMT tuning dial (4, Figure 4-5) with the red TUNE button (5) depressed until a
peak meter indication is noticed. If the meter produces 100% deflection, turn the SENS control
counterclockwise until adjustment of the XMT control yields a peak response less than 100%
deflection. Tighten the locking ring on the XMT tuning dial.
m. Set the MODE SELECT switch to either of the COMMS positions. Establish a communication link
with the corresponding remote unit (unit tuned to receive the transmit frequency of each of the
COMMS modes). The remote unit should be 20 or more feet away from the BDR (preferably at the
expected operational distance). If communication cannot be established, turn the POWER switch to
the 10 WATT position and attempt communication again.
n. Set the MODE SELECT switch to the other COMMS position and establish a communication link with
the other remote unit.
o. Set the MODE SELECT switch to the single directional (TR) or bi-directional (BDR) mode, as desired.
p. Monitor through traffic via the front panel audio connector, with both remote links set for clear
transmission. If the BDR stays keyed constantly, even with no through traffic present, connect a
frequency fill device to each radio and reprogram the squelch level to a higher setting. Alternatively,
all radios (including the remote links) can be programmed with CTCSS tones.
q. Place the DISPLAY switch (1, Figure 4-1) to the OFF position to conserve battery life.
r. Cover the BDR with the frame cover for concealment and for some protection from the elements.
After the above procedures have been successfully completed, the bi-directional repeater is in an operational mode and
can begin to relay radio traffic.
4-5 RECEIVING AND RETRANSMITTING MESSAGES
Whenever the bi-directional repeater is turned on, it is capable of receiving messages and transmitting them (relaying
them) back out. Receive and retransmit messages as follows:
a. Perform the initial power-up and diplexer tuning procedure of paragraph 4-3 to turn on the bi-
directional repeater and prepare it for operation.
b. Set the POWER switch (6, Figure 4-1) to 2WATT or 10WATT. Turn the DISPLAY switch to ON.
c. Ensure the receiver-transmitters are programmed with the proper type squelch settings to receive the
desired modulation format (carrier squelch or CTCSS tones).
d. When a carrier with the proper modulation format is received by the repeater, the RCV LED (3, Figure
4-1) and XMT LED (4) illuminate to verify proper re-transmit operation.
e. If the receiver-transmitter is programmed for carrier squelch and the repeater receives a carrier without
CTCSS tones, with CTCSS tones, or with encryption, the RCV LED (3, Figure 4-1) illuminates to
verify proper operation. If the receiver-transmitter is programmed for a CTCSS receive tone, the RCV
LED (3, Figure 4-1) illuminates only when a carrier with the correct CTCSS tone is received. If an
encrypted message is received, the RCV LED (3, Figure 4-1) will illuminate. Encrypted messages will
be received and retransmitted even if CTCSS tones are programmed on the receive channel.