TM 11-5820-890-30-4
2-30. TROUBLESHOOTING FLOWCHARTS. Continued
CHART
SYMPTOM
1
RT power supply is shorted.
2
Fails Built-In test.
3
Display fails to blank.
4
“HUB LOW” is displayed.
5
Some dots in display fail to light.
6
No "E C" is displayed during self-test.
7
Fail display in self-test.
8
No 1.5 to 2.5 V p-p, 2870 to 2890 Hz sine wave during rem I/O
test.
9
No “CALL” display.
10
No “00000” display (keyboard
11
N o “ - - - - -” display (keyboard
12
No “FILLn” display (frequency
13
14
15
16
17
18
19
20
21
22
23
24
is inoperative).
is inoperative).
display is incorrect).
RF output is incorrect (DMM reading is not 35 to 39 dBm).
RF output is incorrect (DMM reading is not recorded level minus
4 to 7 dBm).
No SIG display.
RF power is incorrect in PA (DMM reading is not 35 to 39 dBm).
RF power is incorrect in M (DMM reading is not 20 to 25 dBm).
RF power is incorrect in LO (DMM reading is not -7 to 1 dBm).
Incorrect transmit frequency.
Incorrect low receiver sensitivity (900 to 1100 Hz, 14 to 20 V p-p
sine wave is not present or noisy).
No SIG display (low receive sensitivity).
No sidetone with squelch on (sine wave is present).
VOL control does not work (no variance in sine wave amplitude).
Will not receive audio, COMSEC data (sine wave is not present).
2-49
