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Recapped My Predicta Tandem, I don't know what to do
Bob Andersen
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Posts: 802
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#16

01-05-2022, 09:33 PM
Two of the wires are for the AC tube filament supply.

Sounds like your horizontal frequency is way off. The frequency is determined by one of the couplates near the 6CG7 tube. There is also a coil with a mica cap in parallel that should be set to resonate at 15,750 Hz to help the oscillator stay in tune.

When you are feeding a signal the AFC circuit is trying to get the frequency right. Predictas tend to freak out like in you photo when the horizontal get too far off frequency.

Have you tried adjusting the slug in that horizontal coil? The frequency range control plays a part here too.

You should go through the horizontal setup procedure outlined in the service info.
(This post was last modified: 01-05-2022, 09:33 PM by Bob Andersen.)
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RE: Recapped My Predicta Tandem, I don't know what to do - by Bob Andersen - 01-05-2022, 09:33 PM



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