Toshiba TW40F80 - Manual (Page 100)

100
7. CONVERGENCE TROUBLESHOOTING CHART
Fig. 11-6
Pump-up
Convergence output signals correction wave
+30V
-15V
0V
Vertical
Q751
(R/G/B)
Horizontal
Q752
(R/G/B)
Reray OFF Reray ON
Reray ON
Reray ON
Reray OFF Reray OFF
NG
NG
NG
OK
OK
OK
OK
OK
Protect 1
Relay turns on
once but immediately
turns off. Relay operation sound
at power on. No Convergence
correction wave.
Check screen modes
of picture.
Convergence PCB,
pull out of P712.
Check power
supply circuit. Check Q751, Q752
and repair.
Reray OFF
Proceed to "protection
circuit diagnosis procedures".
Check P708 R/G/B
correction wave.
Check voltage at
±15V+30V pump up. Check power supply
circuit.
Are output signals
applied to H, Vblk of P711.
Check DEF PC13.
Check voltage across
±9V+5V Q754, Q755, Q756. Check Q754, Q755,
Q756 and repair.
Check signals of all IC
and associated cirduits.