NEC MultiSync FP1350 - 5-6.Distortion Correction Circuit

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