5-6.Distortion Correction Circuit - NEC MultiSync FP1350 Service Manual

5-6. Distortion Correction Circuit
Check whether the distortion on the screen varies by OSD
distortion correction control (SIDEPIN) or not ?
NG
Check the waveform at CN-DSB pin 11 is present.
OK
Check the waveform at IC5GA pin 3.
OK
IC5A1, Q5A1 or their ambient circuit failure.
OK
Check whether the distortion on the screen varies by OSD
distortion correction control (TILT) or not ?
NG
Check the waveform at C519.
OK
IC511 or its ambient circuit failure.
OK
H OSC/DEF/HV circuit failure. (see item 6 )
NG
Check the waveform at IC511 pin 5.
NG
• IC501, R544 or C524 failure.
• Digital control circuit failure (see item 12)
OK
IC511 or its ambient circuit failure.
NG
IC5GA or its ambient circuit failure.
NG
IC501, R526 or C519 failure.
vertical period
7-15
Sidepin +
Sidepin -
vertical period
Approx.0.5Vp-p.
vertical period
Approx.0.5Vp-p.
TILT min.
TILT max.
Approx. 0.5Vp-p when TILT
control is min. condition.