Toshiba CN27E90 Technical Training Manual page 133

(B) OSD IS OK, PICTURE DOES NOT APPEAR
Check waveform at pin 53 (Y
of Q510. Approx. 0.7V
Check waveform at pin 4 (Y
of Q510. Approx 0.7V
Check waveform at pin 15 (Y
of Q501. Approx 1V
Check waveform of comb Y output.
Check A/V circuit. Go to (C).
OK
input)
2
P-P
NG
OK
output)
1
P-P
NG
OK
output)
1
P-P
NG
NG
2V
P-P
OK
Check I 2 C bus line waveform
at pins 27, 28 of Q501.
Check C203.
Check Q501.
Check waveform of comb Y input.
2V
P-P
OK
Check waveform of comb Y input.
0.4 V (3.58MHz)
P-P
OK
Check Comb Board.
133
OK
Check Q501.
NG
Check I C bus line
2
and QA01.
NG
Check A/V circuit.
Go to (C).
NG
Check Q501.