Vertical Oscillation / Deflection Circuit Failure - NEC DPro2070SB Service Manual

3.4.3 Vertical Oscillation / Deflection Circuit Failure

(Check "3.2.3.2 Vertical Sync Unstable" before checking of this item)
Check the +15V/-15V line.
NG
OK
Check the saw-tooth waveform at Pin 5 of IC401 on the MAIN PWB.
NG
Check the saw-tooth waveform at Pin 7 of IC401 on the MAIN PWB.
NG
Check the vertical control input.
OK
IC401, vertical deflection yoke or peripheral circuits
Check the voltage at Pins 1 and 6 on the MAIN PWB.
Expected failure point
Power circuit (See Item 3.4.1)
OK
NG
IC601, IC401 or peripheral circuits
Expected failure point
Expected failure point
IC401 or peripheral circuits
Check the saw-tooth waveform at Pin 15 of CN600 on the MAIN PWB.
Expected failure point
3-20
(Approx. 3Vp-p)