Even at 2013 money it is not a budget buster. The vacuum variable could; depends on how resourceful you are!!! Tom:::: how many KV would be a minimal cap for this tuner and the PF range???
I am not aware how many built the tuner and did not use a vacuum variable.
I did.
Fred
Hola Fred,
Just like the inductor heat example, voltage rating for the cap depends on the impedance matched and power level used.
Usually, a standard 500 pf vacuum variable cap rated at 10 KV is more than adequate for any matching job or QRO power level up to 160M.
I have used air variables on several tuners and found 300 pf at 4KV handled a standard parallel match quite well at 1500w.
Worst case is the air variable cap arcs over and we need a bigger one. So we have little risk trying whatever we have available for the job. WTF.
T