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Recapped My Predicta Tandem, I don't know what to do
#49

After thinking about it for a while. The symptom of the grid pattern is being obscured by the rolling banding interference. I think the AC interference is getting into the video signal which is coming from the IF section. It's interesting to note the ringing (very fine horizontal lines) is riding on the AC noise.

You really need a oscilloscope to check the DC voltages for AC noise. And looking for distorted waveforms otherwise you are flying blind.

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                                 [Image: http://philcoradio.com/phorum/images/smi...on_eek.gif]  Chris


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RE: Recapped My Predicta Tandem, I don't know what to do - by OZ4 - 01-16-2022, 03:08 PM



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