[NJARC] Advice Needed:

[NICHOLAS SENKER]

At the risk of beating a dead horse, I would like to add my two cents.  I have not come up against this type of problem yet so all the replies were of interest to me for future reference. If I was working on this set, I would just put a fuse in the circuit so I could sleep better and let it go at that.
Nick Senker

----- Original Message -----
From: JOE CRO <n3ibx at verizon.net>
To: New Jersey Antique Radio Club <njarc at mailman.qth.net>
Sent: Tue, 1 Jan 2008 07:56:00 -0500 (EST)
Subject: [NJARC] Advice Needed:

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Happy New Year and Hello to All,
                                                I finally got a "roundtuit" and worked on one of the forgotten orpans of a console radio, namely a Philco 41-290 I picked up at one of our club auctions sometime ago. Besides doing a complete recap, needed tube replacement, even replaced the audio output transformer, etc etc I noticed the power transformer coughed up most of it's original insulating tar on the wooden base it sits on. Having previously read somewhere that Philco's are notorious for having bad power transformers, I approached powering the set up with a bit of caution. I first pulled the rectifier (#84 tube) and powered the set up on a variac to see if teh transformer, or anything else would smoke up. Nothing. Good, on to the next step. I then ramped up the AC voltage again with the rectifier tube installed. (as a sidenote, the original rectifier tube didn't have filament continuity - a bad sign that it may have been taken out by the transformer or other components) and still no smoke. I then went through and did a total paper and electrolytic capacitor replacement, etc etc, and the set came to life. 

Needless to say I was very pleased to now have another good player in my stable of old consoles. I'd like to add that the audio sounds terrific from it's push-pull 41 output into a 14" speaker and correct replacement audio output transformer. 
My question is what do I dfo with the power transformer? It does run warm after playing it for an hour or so. I suspect some of the heat being generated is by convection from the tubes that surround it. I'm just concerned that it's inevitable that it'll eventually short out or become defective; unless I "re-pot" the transformer with some sort of insulating material. 

Has anyone else in our group come across a situation like this? If so, what did you use to repot the transformer? I was thinking of silicone RTV, but due to it's curing properties I don't know if it would be a suitable medium to use. Should I just leave it alone and hope for the best? Again, any advice will be greatly appreciated.

Many thanks in advance for any advice, and a very Happy new year to all. May 2008 bring you more radio that glow in the dark!

Joe Cro N3IBX

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