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AV3000 AVC Unit Service Manual
8. SERVICING INFORMATION
8.1. Diagnostics
Phenomenon
Check
Point
Potential
Problem
50-way cable between AVC and FC4? Cable disconnected
PDP LED is
flashing
Digital interface cable DVI24 or DIN8 disconnected? Cable disconnected
No picture See "AV Board Troubleshooting"
Crystal oscillates?
Dry joint/solder bridge
X100/C135/X101/C136
Component dry joint/solder
bridge/broken in CHROMA lines,
e.g. R208/Q121/Q122
Picture unstable
Comb filter works?
Components of comb clock IC101 pin
19
Noisy picture on
RF (TV)
VIF inputs around pins 1~4 of IC100 input proper signal?
Dry joint/solder bridge at pins 1~4 or
broke device of IC100
Slow response toward R/C handset R319 disconnected
No sound
IC301 pins 58/59 input proper signal (0.1~0.8Vp-p) F-sound-out line component failure
No WSS
response and no
TELETEXT
IC100 pin 32 signal observed?
Pin 32 solder bridge (to pin 31)/dry joint
or in line of CVBS-micro
8.2.
AV Board Troubleshooting
No picture,
power working
Composite,
component in
Check SAW
filter, tuner
& around
Check TR101 & TR100
No Picture
Both
All
No picture
Yes
No
No
Yes
No
RF
Component IN only
No picture
No
Yes
RF, video
in
Pins 49~51
of IC100?
Pin 10 of
IC100?
Check IC100
& around
Pins 16 & 28
of IC08?
Check IC10
between
IC03 & PSF
Pins 1~4
of IC003, signal
observed?
Yes
Check IC02
& parts around
Check pins 1,
2, 21, 22 & 26
of IC08
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