TM 5-6350-264-14&P-12
NAVELEX EE 181-AA-OMI-120/E121 C-7359-60-1
TO 31S9-2FSS9-1-12
Table 5-1. Troubleshooting Procedures - Continued
Corrective action
Probable cause
Trouble
volts/division
e. (cont)
@2v
2. (cont)
time/division
@10ms
input
@dc
Connect scope probe to A2-TP6,
blue. Connect scope ground to
A4-TP3, orange. The scope
should display clock signal as a
squarewave of 6.8 0.4 vdc, and
81.3 to 85.4 ms (11.7 to 12.3
Hz). Maintain this check for a
period of time to ensure that
clock is stable.
b. If clock signal is good, use oscilloscope
to check FSK signal on Data Re-
ceiver PC board A4. Set oscillo-
scope as follows:
volts/division
@2v
time/division
@0.1ms
input
@ac
At the Receiver connect scope
probe to A4-TP6, blue. Connect
scope ground to A4-TP3, orange.
At the transmitter, ground A1-TP5
(green) by connecting a jumper
from A1-TP5 to transmitter chas-
sis. The scope should display FSK
signal as a sine wave of 9 0.5 vac,
and 0.81 to 0.76 ms (1231.9 to
1308.1 Hz). Maintain this check
for a period of time to ensure that
FSK signal is stable.
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