Hi John and group,
Here was my experience from my old QTH. I had a 60ft Rohn55 tower. I tried
shuntfeeding, using 3 tuned insulated radials bent tightly around my meager
70X100 ft lot. I had several Force 12 antennas on the tower, none with
traps. The shunt feed worked somewhat OK I thought, but nowhere near as good
as an Inverted L. Feed the L wire at the base of the tower. Run the wire up
the side, start about 18inches from the tower (you may need to adjust the
distance from the tower later to get the lowest SWR). In my case, I ran the
wire up to about 55ft, then sloped it out to a tree at about 30ft high in
the front yard. I still used the 3 tuned radials for 160 with the Inverted
L. Make the L 1/8 wave long, depending on your planned freq of operation.
Make the L out of the heaviest wire you can find. I used insulated #10.
The antenna worked like a champ for being on a relatively short tower. I now
have 90 countries on 160, many of them from that antenna.
Like me, you really don't have the necessary height to get up a better
antenna for 160.
73 and hope this helps,
Darrell AB2E
>From: "W5JMW John" <w5jmw@cableone.net>
>To: <TowerTalk@contesting.com>
>Subject: [TowerTalk] help with shunt feeding
>Date: Thu, 6 Oct 2005 18:09:28 -0500
>
>With all the talk about shunt feeding.I have a question.I am currently
>using
>3 slopers,(80,40,160) comming off my hdx-555 at abt the 50 ft level.I also
>have a hy-gain hy-tower that is midified for a 40 meter vertical with
>elevated feed.That is to say that a 35 ft element is insulated from the
>lower tower,Third ant is a 140ft dipole fed with open wire.My tower is a
>hdx-555 with a 2 ele 5 band quad on a 12 ft mast.What can I do for 160 that
>would be better?
>Wouls a shunt fed tower be the way to go ?? Should I use the hytower and
>make it back to a 75 meter ant and add a wire to inverted L.All suggestions
>welcome..73,john...BTW my city lot is abt 40 x 80...tnx
>
>_______________________________________________
>
>See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless
>Weather Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any
>questions and ask for Sherman, W2FLA.
>
>_______________________________________________
>TowerTalk mailing list
>TowerTalk@contesting.com
>http://lists.contesting.com/mailman/listinfo/towertalk
_______________________________________________
See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless Weather
Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any questions
and ask for Sherman, W2FLA.
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TowerTalk@contesting.com
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