NEC DPro2070SB Service Manual page 77

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