Jerry,
I started with one radial.. and added inductance here the radial connected to
the base
of the antenna.. wish I remembered what valuee I used .. but I dont. then
trimmed the radial I had
pre cut somewhat longer than 1/8 wl..I dont remember if I used an RF sniffer or
a clamp on ammeter
to trim the radial when you are done each radial will be ballanced to the
correct length and be physically
1/8th wl long but loaded to 1/4 wl.. These seem to work well. My problem at
the moment is that
with the new McMansions next to me I now have all kinds of common mode
problems.
Of course it could be some new appliance or device my wife has added to the
house.. I still have to
resolve it.
Jim
----- Original Message -----
From: "Jerry Keller (K3BZ)" <k3bz@verizon.net>
To: wa3mej@comcast.net
Sent: Friday, November 11, 2011 9:23:44 PM
Subject: Re: Topband: Inverted L antennas.
Hi, Jim.... W3LPL ought to know! Very interesting ideas! I had arrived at
the conclusion that elevated radials were what I want to try, and certainly
1/8 wavelength is a lot easier than longer ones.... however, I'm not sure
what you mean by "1/8 wl long now but they are loaded and tuned to 1/4 wl
electrical length".... how do you tune 1/8 wave radials to 1/4 wavelength?
Jerry K3BZ
-----Original Message-----
From: wa3mej@comcast.net
Sent: Friday, November 11, 2011 5:49 PM
To: topband@contesting.com
Subject: Re: Topband: Inverted L antennas.
I use an inverted L here but it goes to within 6 inches of the ground.
total length is about 160ft
with about 70 vertical. I use a homebrew variable cap to match it. My
radials are 4 loaded radials that
are tuned to be electrically 1/4 wl long.
When I first installed this antenna many years ago it was at the suggestion
W3LPL. After installing
it I got frustrated when everyone else was hearing and working things that I
could not even hear.
A call to Frank helped solve some of the problems.. he told me to walk out
about 6-10 ft from
the base of the antenna, grab the radial throw it up in the tree about 6 or
7 ft above the ground.
Then he told me to disconnect my ground from the base of the antenna.
20 minutes later I was hearing and working all kinds of europeans to include
russians.
Over the years I have made several modifications to the antenna like adding
an UNUN at
the feed point to mitigate common mode problems etc.
The secret is elevated radials and disconnecting the ground at the base of
the antenna... I only use
4 radials that are 1/8 wl long now but they are loaded and tuned to 1/4 wl
electrical length... It works great
Hope this helps the gentleman that is wanting info on inverted L antenna
installation.
Jim WA3MEJ
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UR RST IS ... ... ..9 QSB QSB - hw? BK
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UR RST IS ... ... ..9 QSB QSB - hw? BK
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