Aiwa HV-FX7800 Service Manual page 61

ELECTRICAL TROUBLESHOOTING -9/17
3. System & Front Panel Circuit
A.
Auto stop.
Does SW30 waveform
appear at IC501 Pin 105?
YES
Do Take-up reel pulses
appear at IC501 Pin 49?
YES
Change IC501.
NO
Check the Drum Motor
Signal.
NO
Do Take-up reel pulses
appear at the base of
Q514?
YES
Replace the Take-Up Reel
Photocoupler in the
Deck(RS501).
-61-
NO
Does 5.3V appear at
RS501.
YES
Check the Power.
NO