TROUBLE SHOOTING TABLE
Circuits to be checked: » IC1500, 1501 and its peripheral circuit
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NO VERTICAL SCAN
IC1500
IC1501
Normal
Check the voltage at pin (6) of IC1501 and pin (6) of IC1500.
Abnormal
IC1500
(6)
IC1501
(6)
Check vertical trigger pulse at pin (31) of IC2801.
Check L1500, D1576 and R1576.
IC2801
(31)
L1500
D1576
R1576
Normal
Abnormal
Check IC1500, IC1501 and related circuits
Check IC2801 and its peripheral parts.
IC1500
IC1501
IC2801
Note 1: Make sure that not for the horizontal centering mode. Turn on the service mode. (Short J351 and J352.) Then when you press "- / --" key on the remote you can get in the horizontal centering mode. Note 2: The vertical sync signal must be fed to pin (2) of IC1000 in oder not to activate the vertical no-scan protector. Take this measure with the protector circuit for the troubleshooting on the following pages.
