Stuart you point is well taken. Al's antennas were at best in the most hostile
environment.The antenna was made from coiled copper strip and then with a
motor, it was tuned as a
1/4 wave on whatever frequency that was used.
Al also made the first no-tune amplifier that I have seen. Used two 3-500Z
tubes and aquite complicated tank circuit. It was a Pi L tank with the antenna
tapped at the 50 ohmpoint of the L network. Simply band switch to a given freq
and tune the antenna then youwould have 1.5 to 2kw on the air.
From: Stuart Rohre <rohre@arlut.utexas.edu>
To: tentec@contesting.com
Sent: Tuesday, September 22, 2015 3:19 PM
Subject: Re: [TenTec] OCF Antennas - Which commercial antenna is gest?
True,the theoretical impedance of free space is taken as 377 ohms, but
no earth bound antenna is in "free space", which implies well away from
other couplers, earth, ground, counterpoise, etc.
The nitrogen or helium filled radomes protect a ship board antenna from
the salt air. The condensation of salt air at sea upon a HF antenna can
detune it from optimum operation. That is why your friend's antennas
worked well, they were protected from corrosive salt air.
we fresh water washed down our sea borne or sea side antennas every work
shift before using them for this reason.
-Stuart Rohre
K5KVH
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