Pentranic ch-288 with vertical collapse

mwturnquist

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Fist a little background on this. At first this monitor just had issues with dim dark pictures that came in better after a 10-15 min warm up and it would not always stay in position so adjustments were often needed. I decided that it was time for a cap kit and one was ordered from Bob Roberts. two days before the kit was to be installed the images on the screen went into foldover, So I shut down the game and on restart it went into vertical collapse. I was left with a horizontal line.
OK here is what I have done so far. Based on the horizontal collapse I replaced all the caps that came in the kit in addition I also looked at the schematic and also tested first but still replaced D399, D401, D407, R386, R401, R369, D304, L401, R396 and . none tested bad but were replaced since I had already pulled them out I also replaced IC3. I reassembled everything and powered up. Upon startup I looked and listened for anything unusual.....all good. So now I have the same horizontal line only now it is bright and crisp.
OK so now I am at kind of a loss. I replaced IC3 again for good measure same result. I have also checked My B+ voltage is 122v. Where I am at now is when I checked for 18v at my L401 inductor leg I read 0v and it is also 0v @ R401. checking for Voltage at IC3 I read 30v on pin 6. Should I see some voltage on pins 3 and 7 on IC3 as well, I currently read 0v. I did recheck D399, D401, C326, C393 and R336. They all pass and match schematics. What am I missing, could the flyback be bad? Is there a good test? Checking for opens at flyback I show no opens between pins 4-5, 4-7, and 5-7. Resistance of flyback is 4 to 8 ohms depending on pins I was checking.

Thanks in advance
Mike
 
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