[Amps] PTFE dielectricum variable cap

[pc5m, Carel]

Hi, I would like to get the opinion of this group on constructing a homemade
variable 500 pF/1nF capacitor for my new 160mtrs amp. To get sizes down I am
considering using 1mm (40 mill) thick teflon sheet material as dielectric
(10 times or so capacitance increase when comparing with air construction).
So a sandwich of several stator-PTFE-rotor-PTFE-stator-etc, etc. Capacitor
stress will be around 5KV and 20 Amps of RF current. 

 

Did google a bit,but no hits.should this be attainable ? I think losses of
PTFE are well enough at 2 MHz to cause any heating or change in Eps
R/capacitance and 40 mill will provide enough rigidness and stability ?

 

Thanks, Carel

 

p.s. Yes, of course I do know that vacuum capacitors do exists ...