Tatung VM77S Service Manual - page 23
Manual is about: Tatung Vibrant VM77S - 17" Color Monitor
of
32
Page 22
Troubleshooting
VM77S
5-5 Out of Horizontal Synchronization
5-6 Out of Vertical Synchronization
Check or replace
the signal cable or
H. sync pin 41
of I701.
Check or replace
I401, C406
Yes
Horizontal
sync present at
pin 15 of I401
Check
I401 pin 8 H. output
frequency & pin 29
waveform
Out of Horizontal
Synchronization
No
Yes
No
Check Q401,
T401, Q402,
R424, D401
Check signal cable
& V. sync pin 42
of I701.
Check or replace
C303, I401,
Yes
Verizontal
sync present at
pin 14 of I401
Check
I401 pin 24 waveform
Out of Verizontal
Synchronization
No
Yes
No
Check I401 pin 13 & pin 14.