[AMRadio] Drying out HV transformers / Chokes

Donald Chester k4kyv at hotmail.com
Tue Sep 20 21:09:54 EDT 2005

>I have several 2.5v and 10v rusty,dirty, and rattling UTC small can S 
>series filament transformers that I want rebuild and would like to know a 
>source for transformer varnish and potting material, wax,tar, or whatever.
>On pulling the cover off the most rattling around one I found only sections 
>of corrugated cardboard to be the "packing/potting"  material !!.

Those were the "cheapies" made by UTC.  Their higher quality transformers 
were potted with tar.  Some of the older S series actually had louvres in 
the case for ventilation.  These were essentially open frame transformers 
with a protective case against physical abuse.  Later S series did use 
potting material.  These were the lowest quality transformers UTC made, and 
their ratings are for intermittent amateur service.

Don k4kyv

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