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Hello, Working on a restoration of a Philco 89. Radio plays on dim bulb but poorly. Need to recap yet. my question is there is wax on the chassis around the power transformer and also inside the bottom of the transformer. More than I would like to see. I think there was a melt down long time ago as the wax on the chassis is coated with dirt. As I said the radio plays. I ohmed out the windings and they are close to what the schematic says. The voltages are what I would expect with no load. Just wondering if the transformer is sound. Any thoughts? I plan to replace the wire as far into the transformer I can as they are all stiff and fragile. I have done this many times and it works out well.
Thanks,
Dan
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My suggestion is to remove all tubes and lamps. Throw the transformer on a variac and slowly raise the voltage in increments of 10 volts while monitoring the current draw.
Your looking for basically zero current with no erratic changes in current as the voltage is increased up to the operating voltage stated for the radio. Let it run for about 15 minutes and if you don't see the current movement as previously mentioned you should be good to go.
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It's not unusual to see a waxy residue under and around a power transformer. I would pull the rectifier and turn the radio on, after about 30 minutes, if the transformer is only slightly warm, call it good.
Steve
M R Radios C M Tubes
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Guys, Thanks for the suggestions.
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Hello dconant,
Are you sure that wax is not from a old wax coupling capacitor .
Sincerely Richard
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Yes as the wax is on top of the chassis and inside the transformer can.
Posts: 130
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Joined: Jun 2022
City: Marion
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Just wanted to state the radio has been playing quite well and the transformer is running just warm. So looks like I got lucky on that transformer.
Thanks all for the help.
Dan