Topband: T - vertical improvement

[Mike]

Great discussion, is there a good source of vacuum variables (at reasonable prices)
for this application.  Everything I've found has been in the $300+ dollar range?



________________________________
From: DAVID CUTHBERT <telegrapher9 at gmail.com>
To: Roy <royanjoy at ncn.net>
Cc: topband at contesting.com
Sent: Wednesday, July 22, 2009 4:38:43 AM
Subject: Re: Topband: T - vertical improvement

The radial system you have will be fine. What you give up is matching
simplicity. The T will need a base series capacitor as a minimum and an
L-network if you like a 1:1 VSWR. At 1.5 kW the 370 pF cap will see 10 kV
RMS. You are looking at a vacuum variable capacitor.


    Dave WX7G