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Re: Coil form



Hi all,
        Brad wrote...               

<snip>
> And second has anyone used epoxy glass circuit boards with the coper etched
> off for a border as cap plates wet or dry in reguards to my post about the
> big TC coil plans? The only source of large pc boards I have found at a
> reasonable price is Electronics Goldmine, but they are double sided could
> they be separated by PE sheets? Thanks again.

I have built a couple of PCB plate caps using double-sided PCB with
borders removed. They worked reasonably well, but it is difficult to 
quantify as I was just getting going on a new system (rotten tune and 
all that). The major failure mode was arcing around the ends. I was
running this cap in engine oil (never again - it carbonizes much too 
easily). I've often wondered just what the merits of fibreglass are.
Plenty of low powered RF circuitry is constructed on these. Even
stuff in the 100's of MHz range. In fact stripline filters and 
transformers are etched in as part of the circuits. The losses can't
be too bad (at least at low power). I might have another crack at
some stage but this time in transformer oil when I have a better
controlled system running.

Malcolm

** If it's under 10 Amps it's leakage current **