Zenith XBV 443, Service Manual

Page: 23 / 108

3-14
3. Y/C CIRCUIT
(4) When the Video signal doesn’t appear on the screen in REC Mode,
Is the EE signal normal?
Is 5.2V/5.3VA applied to the
IC301 Pins 4, 22, 47, 60, 84?
Does the REC RF signal
appear at the IC301
Pin76?
Check EE Mode.
Check the system of
REC”H”(IC501 pin74)
Replace the IC301.
Check the SW 5V/ 5.3VA
Line.(Power Circuit)
Check PB Mode.
Does the REC “H”(4V~5V)
signal appear at the Q303,
Q307 Base?
Check the REC Luminance
Pass and Color Pass.
Does PB Mdoe operate
normally?
YES
YES
YES
Does the REC RF signal
appear at the IC301
Pins86, 90?
Check the Drum &
Drum Connector.
YES YES
YES
NO
NO
NO
NO
NO
NO