Abnormal Display(The Relative Video Amplifying Circuit) - Philips 109B7 Service Manual

19" CDT Color Monitor
7-4. Abnormal Display （The Relative Video Amplifying Circuit）
Check IC801 Pin9 VCC about 12V
OK
Check IC801 Pin5、6、7
(R,G,B)input signal
OK
Check IC801 Pin23 vice pulse
and Pin24 blanking signal
OK
Check IC801 Pin19, 20,21
three gun output signal
OK
Check IC801 Pin1, 3,4(R, G,
B) zoom circuit output
waveform
OK
Check the voltage of CRT tube
socket R, G, B cathode about
65V and the waveform
NG
Check the relative circuit of 12V
NG
Check signal source and
video card
NG
Check IC101 Pin8 and horizontal blanking
relative circuit.(references Item5)
NG
Check IC801 and IC802
NG
References Item3
NG
31
Check the relative circuit
of IC803
109B7