[Boatanchors] Drying power transformer

[Brian Clarke]

Hi Vic,

TV-type power transformers were usually sealed up with polyurethane-style varnishes 
rather than wax or pitch. The likelihood of your getting water through such a coating 
is very small.

I'ld be inclined to carry out a HiPot test - you know, very high Voltage with current 
limiting and measure the leakage current between windings and to frame.

73 de Brian, VK2GCE.
  Vic asked:

  I have a TV-type power transformer that a friend recently gave me which was 
  sitting in his garage for several (maybe more than several) years.  He hooked it 
  up and measured voltages, which are within spec.  The question is, before using 
  it in a project, should I put it in the oven for a few hours at low temperature 
  (say 150 f) to drive out any moisture?