Quote:
Originally Posted by D Cassidy
May I ask why you are using oil rather than a potting compound?
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Hi there, it's a good question.
Oil has a lower specific heat capacity, so the resistors can do their job without overheating. The oil will heat much faster.
I'm also not convinced that a flashover would still not occur inside the potting compound, along the body of the resistors, since we're dealing with RF currents at a very high power. I can visualise this travelling down the body of the resistor even inside the potting compound. That can't happen with oil as it will to some tiny but sufficient extent penetrate the body material of the resistor.
The difficulty with the coax issue may have been resolved now. I am only now dealing with a bare copper lead-out wire. The coax will now be external to the unit.
I'm trying a combination of epoxy resin around the inside of the lead-out wire and Wellseal on the inside and outside.