NEC DPro2070SB, Руководство по обслуживанию

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3-3
OK
Expected failure point
1) IC701, Q701 or peripheral circuit
2) T701 (FBT), C726, R720 or peripheral circuit
OK
NG
Check the R/G/B video output.
Expected failure point
Video circuit is (See Item 3.4.5
)
OK
NG
Measure the R/G/B video output at Pins R, G and B of CRT socket.
GND
Normal
65 to 75Vdc
Normal
35Vp-p
Check the heater voltage.
Expected failure point
CN202, CRT socket, CRT or peripheral circuit
OK
NG
Measure the (heater) voltage at Pin 7 of CN202 on the CRT PWB.
Check the screen voltage.
Expected failure point
T701 (FBT), CRT socket or screen lead
OK
NG
Measure the voltage of CN201 on the CRT PWB.
Usually, the screen voltage is 600 to 800.
Expected failure point
CRT socket or CRT
Is the high voltage maintained at approx. 27kV?
CONTINUE