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Re: Cardboard secondary forms...
Tesla List wrote:
>
> >From chip-at-poodle.pupman-dot-comSat Nov 9 21:50:43 1996
> Date: Sat, 9 Nov 1996 21:20:54 -0700 (MST)
> From: Chip Atkinson <chip-at-poodle.pupman-dot-com>
> To: Tesla List <tesla-at-poodle.pupman-dot-com>
> Subject: Cardboard secondary forms...
>
> Greetings,
>
> My experience with a cardboard secondary tube was poor. Admittedly it
> was my first coil, but it shorted out by arcing through the cardboard and
> down the inside. I would suggest, as Ira Groff pointed out, that if you
> use this type of secondary coil form, coat it with something like an
> epoxy resin first.
>
> Chip
>
> =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-> Chip Atkinson
> http://bhs.broo.k12.wv.us/homepage/chip/info.htm
> --- Everyone is someone else's weirdo. ---
> =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-Chip,
My experiences with fiberous materials for resonator forms (phenolic,
cardboard), is the material will absorb water rapidly. Any water
absorption will kill the Q of the resonator, and will be an additional
parasitic capacitive load the Tesla system must drive. If this material
must be used, it should be baked in an oven to drive out trapped
moisture, and then immediately coated with a epoxy, or poly-urethane
sealant.
Also, make sure NOT TO ALLOW WIRES TO PASS INTO THE INTERIOR OF
A RESONATOR, at the base or electrostatic load end; at high power the
coil will flashover and cut a spirallic shape carbon track down the
interior of the coil form. It has happened to me. :-(
Dave Sharpe, TCBOR