3. SERVO CIRCUIT (1) Unstable Video in PB MODE
Unstable Video in PB Mode. YES Does the Noise level of the screen change periodically? YES Does the CFG waveform appear at the IC501 Pin67? YES On tracking do the CTL pulses move? YES Does the Video Envelope waveform appear at the IC501 Pin82? YES Replace the IC501. NO Refer to �When the Y signal doesn�t appear on the screen in PB Mode�. NO Replace the IC501.
Refer to �(2) No 12VA of Power section�
(2) When the Drum Motor (2) doesn�t run.
When the Drum Motor doesn�t run, YES Does 12V appear at the PMC01 Pin8? YES Does 2.8V appear at the PMC01 Pin12? Check the connector (PMC01) and the Drum Motor Ass�y. NO NO
Do the Drum PWM Pulses appear at the IC501 Pin34? YES Aren�t the foil patterns and the Components between IC501 Pin34 and PMC01 Pin12 short? YES Do the DFG Pulses appear at the IC501 Pin104? YES Do the Drum PWM Pulses appear at the IC501 Pin34?
NO YES Do the DFG Pulses appear at the PMC01 Pin11? NO Replace the Cap M.
NO
Aren�t the foil patterns and the Components between IC501 Pin 104 and PMC01 Pin11 short? Replace the IC501.
NO
Aren�t the connecting patterns and the Components between IC501 Pin34 and PMC01 Pin12 short? 3-9