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Old 9th Mar 2018, 5:17 pm   #35
Keith
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Join Date: Jan 2003
Location: Tewkesbury, Gloucestershire, UK.
Posts: 690
Default Re: Bush TV22 restoration

I pleased to report a bit of a breakthough. The random line jitter was not interference due to corona in the LOPT. The cause was actually a wiring error introduced by a previous "repairer". Along with the substitution of the metrosil by a 1N4007, the A1 smoothing capacitor C31 had also been replaced. But instead of connecting it's cold end to 0v, it had been moved two tags along to the junction of C26/C28 i.e. the line sync drive. Correcting this completely removed the random jitter. Next job is sorting out the line tearing/ringing after frame flyback.
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