> Well, my problem was that my capacitance on my old tuner was pretty much
> maxed out. I couldn't add more. Believe me, I remember our conversation.
> But when the cap is fully meshed when it arcs, there's not a lot one can
> do.
Unfortunately wider spacing increases voltage at the same rate as
the wider spacing increases voltage rating when as you are using
far less than optimum capacitance. You really gain nothing, for a
certain physical size capacitor, unless the antenna impedance is
very high. Power handling can actually decrease by increasing
spacing at low and moderate antenna impedances, for a fixed
capacitor length.
The solution is to use enough capacitance to have operating Q as
close to minimum as reasonably possible. The ARRL Antenna
Handbook comes with some nice software for looking at tuners, it
is interesting to play with values and look at voltages (I use a Lotus
123 spreadsheet I wrote).
You'd be amazed at the problems T networks have on 160 and 80
when matching low load impedances and capacitive reactance
loads when the tuner C is too low.
My ATR 30 by far outdoes my old KW Johnson Matchboxes, which
are now all stashed away in a storage building. Of course I have no
idea how the latest Hrevnek? tuners are, I've only seen the units
from Viewstar and Vectronics. It might be much better engineered
than past products.
73, Tom W8JI
W8JI@contesting.com
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