G07 chassis too bright

KorbenD

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Won't adjust down, screen is washed out with retrace lines.

Previous symptom was high voltage shutdown, and I just put a Bob Roberts repair kit in it, which brought it (mostly) to life.

X303 tests ok, any other suggestions what to check?
 
Check the cap you put on the neckboard. Make sure it is in correctly, and no solder bridges or lifted traces are there. Problems with this cap (C107 - 10uF 250v) will cause this problem...
 
Has the black coating on the back of the tube been wiped off, worn off, flaked off? A CRT without the aqadag coating on the back of the tube can cause this.
I just went through this with a k4600 that was left out in the weather. The chassis was fine, but the tube had a large portion of the coating flaked off and no matter what, I could not adjust the screen voltage down enough to get rid of the retrace lines.
 
Could also be something like the grounding strap that goes around the back of the tube being disconnected allowing voltage to build up. (working in conjunction with the aquadag)
 
Cap on the neckboard is correctly installed. No cold solder joints or cracks on the neck board, no solder bridges.

The tube is fine, a second G07 chassis I just finished works beautifully when connected to it.

I'll write down the voltages at x303 and other places and compare them. Something might be measuring good, but breaking down under load.
 
Found the problem. Voltages on X101, X102 and X103 were way too low. Started tracing it back and found a crack right at the edge of the solder pad on pin 6 of the flyback.

Patched it and the screen control works fine.
 
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