[Lowfer] question about drilling holes in plastic coil forms

[W5JGV (Ralph Hartwell)]

> read on the net also that this causes the plastic to be more
> like an air dielectric, and maybe a little less lossy. Has
> anyone tried both methods, and saw any improvement with the
> holes versus solid plastic ??

Theoretically, yes, it will reduce the losses if you fill it full of
holes.  Personally, I never bothered to drill any holes on the forms I
used for my 166.5 KC gear.  Most large buckets are made from
Polyethylene, which has pretty low loss, even at microwave frequencies.
I never noticed the plastic itself becoming warm from the effects of the
RF, just from heat conducted from the wire in the coil.  Even PVC
generally works FB.  After all, the Tesla Coil guys and gals use it for
the forms for their secondary coils running at multi-mega volt levels
with no problems.

73,

Ralph   W5JGV - WD2XSH/7