TM 11-5895-1090-34/TO 31 R2-2TSC-152
Table 4-7. Low Power Alarm Assembly A5, Test and Troubleshooting
Step
Test conditions
Normal indication
Remarks
ALARM OPERATION
1
Perform the initial procedures in paragraph 4-8.
2
On the test fixture, turn the +14V, +15V and -15V
switches to ON.
3
Readjust the +15V power supply to +15 +0.2 vdc,
- 15V power supply to - 15 +0.2 vdc, and the + 14V
power supply to + 14 +0.2 vdc.
4
On the test fixture, turn the three potentiometers
RF LOW lamp and PA NORM
Check Q1 and Q2, U1, and
INPUT LEVEL, OUTPUT LEV A and OUTPUT
lamps ON.
relays K1 and K2.
LEV B fully ccw and turn switches PA, A, B
INHIBIT to the OFF position.
5
Slowly turn the potentiometer OUTPUT LEV B
RF NORM lamp and PA NORM
Check U1, Q, and K1.
clockwise until LOW RF lamp goes off and RF lamps
ON < 30 mv.
NORM goes on test fixture. Measure and record the
voltage present at UUT TP K using the dvm.
6
On the test fixture, slowly turn OUTPUT LEV B
O to 8 mv less than reading in
Check Ul,Q1, and K1.
control ccw until RF NORM lamp goes off and LOW
step 5.
RF lamp goes on. Measure the voltage present at
UUT TP K with the dvm.
7
On the test fixture turn OUTPUT LEV B control
PA NORM lamp OFF
Check Q2, and K2.
fully ccw and INHIBIT B switch to ON.
PA FAULT lamp ON
RF LOW lamp ON
RF NORM lamp OFF
8
On the test fixture, turn switch INHIBIT
PA NORM lamp ON
Check K1, K2, CR5, and CR6.
A to ON.
PA FAULT lamp OFF
RF LOW lamp OFF
RF NORM lamp ON
9
On the test fixture turn switch INHIBIT
PA NORM lamp OFF
Check K1 and K2.
A to OFF.
PA FAULT lamp ON
RF LOW lamp ON
RF NORM lamp OFF
10
On the test fixture, turn PA INHIBIT
PA NORM lamp ON
Check CR5, CR6, K1,and K2.
switch to ON.
PA FAULT lamp OFF
RF LOW lamp OFF
RF NORM lamp ON
11
On the test fixture, turn PA INHIBIT
PA NORM lamp OFF
Check K1 and K2.
switch to OFF.
PA FAULT lamp ON
RF LOW lamp ON
RF NORM lamp OFF
12
On the test fixture, turn switch INHIBIT B
PA NORM lamp ON
Check Q2 and K2.
to OFF.
PA FAULT lamp OFF
RF LOW lamp ON
On the test fixture, slowly turn the INPUT
RF NORM lamp OFF
13
LEVEL control cw until the PA FAULT lamp goes
52 to 60 mv
Check U1, Q2, and K2.
on and PA NORM lamp goes off. Measure and re-
cord the voltage present at UUT TP H on the test
On the test fixture, slowly turn the INPUT
14
LEVEL control ccw until the PA FAULT lamp goes
0 to 8 mv less than reading in
Check U1, Q2, and K2
off and PA NORM lamp goes on. Measure and re-
step 13 above.
cord the voltage present at UUT TP H using the
dvm.
On the test fixture, turn INPUT LEVEL pot
15
fully ccw and the OUTPUT LEV A control to the
On the test fixuture, turn the OUTPUT LEV
16
B control cw just until the LOW RF lamp goes off
215mv+20mv
Check U1,Q1. AndK1.
and the RF NORM lamp goes on. Record the voltage
present at UUT TP K using the dvm.
On the test fixture, slowly turn the OUTPUT
17
LEV B ccw until RF NORM lamp goes off and LOW
0 to 8 mv less than reading in
Check U1, Q1, and K1.
RF lamp goes on. Measure the voltage present at TP
step 16 above.
K using the dvm.
Set all the DC power switches on the test
18
fixture OFF and disconnect UUT.
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