Marty:
I had an inv L for Topband before I built a self-supporting tower and
shunt-fed it. For a while I operated both and did A-B comparisons on the
air. The tower was 5-10 dB better than the L on TX and RX according to my
S-meter and others' reports on my sigs. I have a single varibale
bread-slicer cap at the base (I run 100 W max) and can match it anywhere
from 1800 to 1950 kHz or so with the rig's internal tuner.
I have admitted before that I may not have built the L properly or had
an adequate radial field underneath it, although I did manage to lay down
about a half mile of scrap insulated copper wire as radials. (The tower's
radial field consist of seven shallow wires, 5 of 100 foot length and two of
35 foot length, plus 130 plus feet of deeply-buried lightning radials and
ground rods.) So the superiority of the tower might be explained by a poor
radial field for the L. But that's my experience with shunt-feeding. I'd
say do it and you'll probably be pleased with the results.
73 de
Gene Smar AD3F
----- Original Message -----
From: "k8mv%k8fc.com" <k8mv@k8fc.com>
To: <Topband@contesting.com>
Sent: Wednesday, May 02, 2012 9:21 PM
Subject: Topband: Antenna
> Need some help. Came home from Florida to find damage to most antenna
> systems here. Have been using 50 foot high inverted L's on 160 and 80.
> Want to see it shunt feeding tower will be better but no software to do
> that. I have 52 foot of Rohn 25 with a TH6DXX and A3WS on top. Already
> have 80 radials out under the L's. The L's will go. Can somebdoy plot
> this thing? One thing I can not live with is a very narrow bandwith. I
> run the station remotely via the internet in the winter. Any help would
> be appreciated.
>
> 73's
>
> Marty, K8MV
> _______________________________________________
> UR RST IS ... ... ..9 QSB QSB - hw? BK
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UR RST IS ... ... ..9 QSB QSB - hw? BK
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