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  #1  
Old 05-17-2017, 02:27 PM
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Check the value of the cap across the Oscillator coil, make sure you used the correct value.

I have mistakenly put in a .00* instead of a .0* on several occasions, that will throw the frequency so far off you can;t adjust it out.

Another possibility is someone in the past adjusted the Horiz coil to compensate for a bad cap and when you replaced it it's now way off.

I don't know this chassis or have a schematic so I'm guessing that in addition to the regular Horiz Hold control on the front , it has an adjustable Horiz coil somewhere in the Oscillator circuit, a coil with a slug most often, find that and give it a tweak and see what happens.
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Old 05-17-2017, 02:29 PM
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And yes, a bad Mica could be throwing it off, there have been more and more reports of failed Micas recently, even they don't last forever I guess.
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Old 05-17-2017, 04:31 PM
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When you say horizontal coil, do you mean the horizontal frequency, drive or linearity controls?
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Old 05-17-2017, 06:09 PM
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Frequency of course.
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Old 05-17-2017, 06:27 PM
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Here's an example, it's an Admiral but probably older than yours and a different model, same idea though.

Coil L20, B1 would be the adjustment I would look for, and make sure the capacitor C61 across the coil is the correct value for your set.
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  #6  
Old 05-17-2017, 07:55 PM
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The squealing noise is sometimes of mechanical origin. If it's still there, try tightening the flyback clamp nuts and mounting hardware.
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Old 05-17-2017, 06:19 PM
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What's the model number of the set?
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Old 05-17-2017, 06:24 PM
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321k47
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Old 05-18-2017, 05:26 PM
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Sounds like a short somewhere, is there a doorknob cap in that set ?
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Old 05-18-2017, 08:28 PM
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There is a doorknob cap in this set. How do you test them, a continuity check?
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  #11  
Old 05-18-2017, 09:34 PM
old_coot88 old_coot88 is offline
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Since you weren't getting any arc off the HV rectifier plate connector (even with the connector lifted and floating), what does that tell you?
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Old 05-19-2017, 05:06 AM
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Ok I missed that...
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Old 05-19-2017, 08:49 AM
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I'm not sure old coot-what does it tell me?
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Old 05-19-2017, 08:57 AM
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If you can't draw an arc from the fly lead that normally connects to the HV rect. top connection, when that lead is disconnected from the HV rect then it means the fly is not generating any HV.

Timmy was suggesting that you test to see if the doorknob was loading down the HV...Which is irrelevant at this point because if there is no HV to load down.
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Old 05-19-2017, 12:20 PM
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With power applied, what color is the 6BQ6 plate, black or red...?
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