Trouble Shooting Flow Chart - ViewSonic E70FSB-2 - E 70F+SB - 17" CRT Display Service Manual

6. Trouble Shooting Flow Chart

6-1 NO RASTER, CRT RELATIVE CIRCUIT PROBLEMS
CHECK MAIN PCB POWER
CHECK
SUPPLY 57.5V,14V,80V
53V, 14V, 80V
CHECK THE HIGE VOLTAGE OF
CHECK
CRT ABOUT 24.5~26.5KV
OF CRT ABOUT 25.5 ~
CHECK THE VOLTAGE OF
HEATER ABOUT 6.3V
CHECK SCREEN VOLTAGE
400V TO 600V
BRIGHTNESS SET TO MAX.
CHECK CRT G1 VOLTAGE
CHECK VOLTAGE OF THE
CATHODE ABOUT 65V TO
ViewSonic Corporation
MAIN PCB POWER
NG
OK
THE HIGE
NG
OK
NG
OK
LESS THAN 300V
OK
NG
OK
NG
CHECK POWER SAVING
H-SYNC, V-SYNC
Q909,
REFER ITEM S.M.P.S.
CHECK FAILSAFE CKT
PIN 25 RELATIVE CKT.
CHECK CRT'S HEATER
CIRCUIT Q907,
CHECK FBT
CHECK BRIGHTNESS CIRCUIT
CHECK
Q705 RELATIVE CKT.
Q705 RELATIVE CKT.
REFER ITEM 6-2
"ABNORMAL
16
Confidential – Do Not Copy
OK
BRIGHTNESS
E70f-5_E70fB-5_E70fSB-5