No Blanking; Hor./Osc/Def/Hv Circuit Fault - HP D8904 Service Manual

CHECK THE RELATIVE
CIRCUIT OF BLANKING
OK
CHECK R859 ON VIDEO PCB,
CHECK G1 RELATIVE CIRCUIT
FBT PIN 5 ON MAIN PCB
1. NO RASTER (DISCONNECT WITH SIGNAL CABLE)
CHECK IC401 PIN 29 ABOUT 12 VDC
OK
CHECK IC401 PIN 26 WAVE FORM
ABOUT 3Vpp
OK
CHECK THE COLLECTOR VOLTAGE
OF Q402 ABOUT 20Vpp
OK
CHECK THE COLLECTOR VOLTAGE
OF Q403 ABOUT 1200Vpp AT FH:31KHz

6-3 NO BLANKING

NG

6-4 HOR./OSC/DEF/HV CIRCUIT FAULT

NG
NG
NG
NG
CHECK THE RELATIVE CIRCUIT
OF Q601, Q707
CHECK IC401 PIN 29 RELATIVE CIRCUIT
CHECK IC401 PIN 4~7, PIN 13
RELATIVE CIRCUIT
CHECK Q402, T401
RELATIVE CIRCUIT
CHECK T401, T402, Q402, Q403,
D408, C418, C419, H-DY, B+