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  #18  
Old 03-24-2017, 01:17 AM
EdKozk2 EdKozk2 is offline
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Join Date: Mar 2014
Location: Elkhorn, WI
Posts: 542
Tim,
Since you don't have a scope you could try to isolate the trouble better. Disconnect/ unsolder C61 250mmf from pin 4 of V9. Leave C61 disconnected and then turn on the set. The picture should roll but, see if you can adjust the vertical size, if so set it. Next see if the vertical hold control has any effect on the vertical roll. If you can get the vertical roll to almost stop with the vertical hold in mid-position thats good. If the vertical hold has no effect or won't slow down enough then the trouble could well be a bad cap or resistor. The bad cap or resistor would determine the time constant the free running vertical oscillator frequency.
If the vertical roll can be slowed down and controlled, then I would next start checking the output of the sync separator. Try connecting a voltmeter set on AC volts, high range to start, to the end of the disconnected C61. You should be getting an AC voltage reading of some sort. You may have to adjust your voltmeters range downward to get a better reading. If there is no AC voltage present then the trouble is syn related. The integrated sync pulse voltage is what your trying to measure. Try these steps and let us know the results.
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