C2, TM 11-6625-564-45
ceiver-transmitter installations. W h e n d e -
and power relay K1 in the receiver-
pressed, the switch completes the circuit to
transmitter. T / R l a m p D S 1 l i g h t s .
ground for automatic relay operation.
(3) T / R + G . A g r o u n d i s p r o v i d e d f o r
T/R+G lamp DS2 and guard receiver
relay K6 in the receiver-transmitter.
1-7. Test Set, Radio TS-1962/ARC/51X
T/R+G lamp DS2 lights.
(4) A D F . T h e g r o u n d p r o v i d e d i n t h e
operation in (3) above is removed.
a. Main Audio. The main audio output sig-
The ground is now applied through
nal from the receiver-transmitter is applied to
ADF lamp DS3 to ADF relay K8 in
HDSET H-101A/U jack J9 through RF DET
the receiver-transmitter. ADF lamp
switch S1 in the OFF position, AUDIO GAIN
control circuit R1 (test unit control head) and
f. PTT Switch. When PTT switch S3 is set
transformer T1. The test headset microphone,
to ON or MOM ON, a ground is applied
connected to HDSET H-101A/U jack J9, ap-
to XMIT lamp DS4 and T R relay K2 in the
plies a voice signal to audio amplifier 3A1 and
receiver-transmitter. The XMIT lamp, DS4,
then to MIC SELECT switch S2. When the
MIC SELECT switch is set to HDSET, the sig-
nal is applied to the modulator and audio mod-
g. SENSITIVITY Control and SQ
ule A4 of the receiver-transmitter.
Switch. The SENSITIVITY control varies the
sensitivity of the main receiver in the receiver-
b. Antenna Signal. The modulated rf out-
transmitter. When the control is turned ex-
put of the transmitter is applied to the detec-
tremely clockwise to the SQ DIS position, SQ
tor circuit from the receiver-transmitter when
DIS switch S5 provides a ground to squelch re-
RF DET switch S1 is in the ON position. The
lay K1 to remove all squelch action of the re-
detector removes the modulated intelligence
and applies it to HDSET H-101A/U jack J9
through RF DET switch S1, AUDIO GAIN
h. FREQ SELECT Switches S1, S2, and S3.
control, and transformer T1.
The switches provide a ground path for the
various frequency selection switches in the
c. DUM MIC Input. When an external au-
mechanical tuner module in the receiver-trans-
dio signal is applied to the DUM MIC jacks,
mitter. In this way, the function of the radio
the signal is routed to the modulator and au-
set control may be simulated for test on the
dio module A4 of the receiver-transmitter
through MIC SELECT switch S2 when the
switch is in the DUM MIC position.
i. AUX AUDIO.
power is applied to the auxiliary audio load
d. Power Input. Plus 27.5 volts dc is sup-
and AUX AUDIO jacks J10 and J11. Jacks
plied to the test unit at PWR jack 55. The
J10 and J11 provide test points to measure au-
power is distributed to audio amplifier 3A1
xiliary audio power.
and three lamps (T/R, T/R +G, and XMIT)
when POWER circuit breaker CB1 is set to
j. Test Jacks. The +225V jack J13 provides
a test point at which the adf plate power can
e. Function SELECT Switch. FUNCTION
be checked. The +27.5V jack J12 provides a
SELECT switch S4 has four main positions and
test point at which the +27.5-volt dc pri-
operations as follows:
mary power can be checked. C A R . R E L A Y
jack J15 provides a test point at which re-
(1) OFF. No power is being applied to
ceiver-transmitter squelch relay K1 can be
checked to determine whether the relay is en-
(2) T/R. A ground is provided for T/R
ergized of not. AVC jack J14 provides a test
lamp DS1 and power relay K1 in the
point at which the avc amplifier voltage in the
receiver-transmitter. T/R lamp DS1
receiver-transmitter can be checked.