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Recapped My Predicta Tandem, I don't know what to do
#56

From the video it almost looks like he has an extreme vertical foldover where the top of the picture is superimposed on the bottom. 

Without a scope its really hard to tell, but instead of a vertical deflection sawtooth wave, he seems to have something like a distorted triangle wave vertical sweep. The deflection signal rises linearly but then instead of falling sharply it decreases as a slower rate which produces a folded over superimposed image.

There also seems to be some hum modulation of the vertical sweep where a 60 hz signal is beating with the 59.94 vertical frequency, causing the image to slowly vertically roll about the foldover point at the difference frequency.

Is there any way that you can get your hands on an oscilloscope, because I don't think you can easily troubleshoot this any further without one.


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RE: Recapped My Predicta Tandem, I don't know what to do - by Mondial - 01-17-2022, 05:07 PM



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