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Set the VOLUME slide VR lever to the highest position. Set the CW/RTTY selector to RTTY side.
After thus setting, is the AFSK monitor sound oscillated when SEND-AUTO-RECEIVE selector is set
to SEND and does the oscillation stop shortly after the selector is returned to RECEIVE position?
Probable causes are trouble of crystal oscillator
or dividing circuit, failure of Computer or
wrong setting of CRTC. In the first place, check
the crystal oscillator and dividing circuit.
Trouble in CRTC block
Check the frequency of the following parts in the numerical order (checking of crystal oscillator, di-
viding circuit):
1. Pin 6 of IC5 (13.5168 MHz)
2. Pin 9 of IC3 (6.7584 MHz)
3. Pin 5 of IC3 (3.3792 MHz)
4. Pin 39 of IC31 (3.3792 MHz)
Output has ceased to come out normally;
trouble of initially checked part.
Is the output of pin 37 of IC31 844.8 kHz?
R76 is broken; C32 is shorted; trouble of RESET switch or
switch wiring; breakage of IC27, IC18, IC2, IC32, IC31
Computer is not working normally
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