Stuart;
Balanced antennas are of course the better choice and in fact are my
preferred antennas. However, for those of us who are fighting
[unconstitutional] antenna restrictions are forced to use stealth or
otherwise hidden antenna techniques to fool and deceive our neighbors.
Typically the antenna of choice is either a random or resonant length of
wire against ground (or a counterpoise). In my current situation I use a
200 foot (random) wire and an SGC-230 remote antenna tuner located right at
my "reasonably excellent" ground system. With this set-up I am able to work
160 thru 6 meters worldwide and have no detectable RFI problems or "hot
spots". This was not true when I used a manual tuner located in the shack
with a ground lead that had to be about 12 feet long. So it is quite
possible to use end fed wires with very good worldwide results and no RFI
problems to deal with.
Reid, K7YX
-----Original Message-----
From: Stuart Rohre [mailto:rohre@arlut.utexas.edu]
Sent: Monday, June 11, 2001 2:03 PM
To: Jack, W7EJJ
Cc: tentec@contesting.com
Subject: Re: [TenTec] Ten Tec & RF sensitivity
A long wire is a fairly useless antenna, (flame suit on, HI), having way
too high an impedance (3000 or more ohms plus reactance), for most
transmatches, even if you are getting one to one, it is all RF loss in the
transmatch I will wager. The long wire mainly has response off its far end,
and depending on exactly how long may have some other lobes, but is so
directional I would not use one again as a general antenna. I HAD a 400
foot one in 9M2 land, and could never get it to not have RF in the shack on
the case of every radio at 50 watts!
I had very poor ground conductivity there, do you? I would try a quarter
wave counterpoise insulated wire around the base board or out the shack
wall, if you can.
I started out radio with Marconi antennas, and never did any real good until
I got a dipole. Now I use balanced antennas either vertical dipoles or
horizontals, loops, quads or Yagis.
73,
Stuart K5KVH
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