GO7 board re-capped but no go.

Pilot53

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I recapped, re-flowed, changed HOT, Flyback, fuses, checked the board with a magnifying glass. Put it back in. No Go. Turns out, the voltage at the emitter of XO4 is 165 volts DC. It cannot be adjusted down with R909. I checked 909 and it is linear. What could be causing the voltage to remain high? It used to come on if I would plug and unplug the unit until a picture came up. When it stopped working completely, I bought the parts from QuarterArcade.Any thoughts.
This is in a Missle Command, original, with a GO7-CBO 19 inch. No glow on the tube, either. It think the limiter is keeping things off.

Help please. I am in SoCal.

Pilot
 
G07 no joy

X901 and X902 are part of the high voltage section and are suspect if you are having trouble with B+. Also double check for cracks in board if those are good. I tested mine unmounted bot 120 V, bolted it in place and my voltage was way out, cold solder or cracking never was sure what finally fixed it.
 
There was a mention of changing R512 to 80K ohms instead of the 8.2K ohms. Would that help anything? Trying to figure out what could be wrong.
 
Fixed it!!

Stupid me. I put the VR transistor in backwards, and the pins were shorting against the chassis. I looked at everything, and checked the transistor, but found it shorted. Looked at the pins and saw that I put the transistor in upside down, and the pins were shorting. Reversed it, powered up, and bingo, picture!!

Thanks for all the help.

Pilot
 
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