"Jimmie D" wrote in message
news:Ujwsh.298$ch1.65@bigfe9...
I was cleaning up today and came across an old dummy load I had that
looks
like it is made from 2 watt resistors. ITs mounted on a quart size paint
can lid and looks to be a 50 watts worth of resistors. This looks like it
may have been a commercially built unit and I was wondering what the
power
handling capability would be if the resistors were submerged in mineral

Related, sort of:

When I was in Navy ET School in the 1960's, we had a shipboard radio
transmitter lab which used banks of incandescent lamps for the dummy loads.
By the time we got to that phase of the school we understood the concept of
matching to 50 ohms and I wondered then (and now) what the actual impedance
of a bank of light bulbs would be. (Of course it changed with the amount of
power applied, since it lit the lamps more or less brightly.)

Nobody ever explained it. It's a wonder we didn't make more smoke than
light. [AN/SRT-14, AN/SRT-15, for those who've been there & done that.]

Also, for excellent heat dissipation and no conduction, a liquid called
FC-75 is used as a heat transfer medium. They literally immerse the gear in
a tank of the stuff and run it though a liquid-to-liquid heat exchanger.
It's totally inert. We used it in our high power pulse transmitters in ECM
gear and it's apparently still around [
http://news.thomasnet.com/fullstory/473395 ] . No, I don't have any :-(