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46-480 Power Transformer Vibrates
#9

Well here's what I've done thus far.

I completely overhauled the bandswitch along with the whole RF section. Seperated all the wafers from the bandswitch and thoroughly cleaned each one of them. Replaced all original caps and resistors with new components. I replaced all mica caps with silver micas. I installed new tube sockets for the 7F8 and 7H7 along with all new wiring. I replaced one of the chokes on the 7F8 filament. Didn't like the way it looked even though it did read less then 1 ohm. And I'm not really sure what those chokes do.

I went through all three of the IF cans and replaced all the mica caps along with any resistors I found. Installed all new wiring from the cans to their connection points in the radio.

Now my 1K resistor doesn't get hot any more but I still have problems that I haven't been able to isolate even with the signal generator or DVMM. All my voltages are within tolerance and a set of NOS tubes installed although all the tubes that were in it test good. All Loctal pins scraped until nice and shiny. I replaced a few of the caps in the main chassis but everyone I took out was good. Figured I was wasting my time and came here. I did install new E-caps.

The radio is motorboating only when I turn the volume and tone controls up. I still have no reception on any bands and the motorboating is there on all bands with no change.

Any ideas would not only be helpful but greatly appreciated.

Johnny

"It's Nice To Be Nice To The Nice"
Major Frank Burns Mash 4077th


Messages In This Thread
46-480 Power Transformer Vibrates - by Pepperoni - 07-28-2013, 10:18 PM
RE: 46-480 Power Transformer Vibrates - by Pepperoni - 08-22-2013, 08:49 PM
RE: 46-480 Power Transformer Vibrates - by EricS - 09-17-2013, 07:09 PM



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