Daewoo DF-8100, Service Manual

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9
TROUBLESHOOTING
8
TROUBLESHOOTING
Noise appears on the
playback screen.
Is noise diminished by tracking
adjustment.
Noise band is trembled up and
down?
Re-adjust PATH.
Is the height of CTL HEAD normal?
No dust?
Is there problem in CTL Input
circuit and amplifier.
YES
NO
NO
NO
Is there CTL pulse at IC501
pin#97?
Check IC501.
Noise appears on the screen even
though changing tape.
Re-adjust the height of AC HEAD.
Remove the dust.
Check C510,R545~R547
IC 501 pin #91, 92, 98.
NO
Re-adjust PATH.
C-1. Bad playback quality (1)
YES
YES
YES
YES
Noise appears on the Full
playback screen.
Are SW pulse and HA SW normal?
Recheck step B-1
(Bad playback quallty (1)).
Check HEAD AMP connector
and HEAD.
YES
YES
NO
NO
ENVE Wave at P502 pin #4?
Check VIDEO circuit.
Are there SW, HA SW pulse at
IC501 pin #16, 18?
Check PCB Pattern.
Check IC501.
C-2. Bad playback quality (2)
YES
NO
YES
No broadcasting signal
received
Is the output at IC501 pin# 61(CLK),
60 (DATA) normal?
Is SIF,Video output at TMI(RF101)
pin#16,19 normal?
Check IC 501.
Check IC301.
Check P100
YES
YES
NO
NO
NO
Is Video Signal input at IC501
pin#56?
Is there Video output at P100
pin#1?
Check TMI (RF101) Block.
NO
Check Video Buffer Q670, Q671
D. No broadcasting signal received
YES
YES
YES