[shawncao]

Found an open resistor (1ohm 1/4w) in vertical output. The resistor connected to a diode and a capacitor (33uf, 250v). Replaced the resistor and it was burned out again after turned on the TV. Any suggestion?

[shawncao]

BTW the P/N of the pcb where flyback located is PW9533-1.

[shawncao]

Thanks cory. I found 2 caps (33uF 200V); and 1 cap (33uf 250v) which connects with a diode. But none of them seems defect. (I used a multi-meter to check them on board).

[cory]

there should be a capacitor near flyback rated at least 250 volts.follow connector back from crt onto main pcb.there will be a diode and cap right off flyback secondary.change cap.

[shawncao]

The voltage is around 60-70 V. Trying to figure out the defect component now...

[mazmaz]

hello
low voltage in cathods driver (180~200) may cause this problume(check fbt out line to dc circuit diode cap , ....)
if problume not stay in stable mode (variable screen voltage) change fbt
bad video driver circuit too may made this problume(zener diods,driver ic ...)

[cory]

check 200 volt line going to crt neck pcb. if low find capacitor, probably near flyback.

[shawncao]

Thanks, both of you. Let me describe the problem a little more in details.
The screen is bright, the picture is pale but stable, and the white retrace lines are full of the screen. I had tried to turn down the screen control voltage, the retrace lines were gone, but the screen and the picture became very dark. I have already replaced a cap on CRT control board which is attaced to the end of the CRT.

[bbp1]

there can be other faulty comp causing symptom- before condemning tube, I would check electros, res, djs etc. If tube is suspect, there are ways to rejuvenate/ fix problem- but must know what doing- I know from hard won experience & making equipment needed how to do- but really, do you think anyone asking such a basic thing could do it?!- I think not!!.

[minnie]

Try turning down the screen control on the flyback, if it's still there, bad CRT.