Jerry,
I have a similar configuration only not as tall.
I have a 40' universal aluminum tower with a 3EL Steppir on top with
ungrounded elements and a 20' vertical extension above the beam.
I shunt feed it with a 35' arm of 1/2" copper pipe about a foot off the
tower and an omega match. I can resonate it on 80 and 160.
I use it mainly on 80 here and can tune it across the full 75/80 M band with
one of the old heathkit motorized capacitors. It works great
on 80 and less well on 160. My Inverted L seems to do better on 160 at this
location. I have not tried to ground the steppir elements here.
Before we moved, I had the same tower with a Mosley PRO67C3 on top with the
same shunt feed setup. At that location (only about 1 mile away) it worked
great on both 80 and 160. I think the smaller top load of the Steppir makes
a difference on 160.
I have 30+ radials here of widely varying lengths.
Dick, K4IQJ...
----- Original Message -----
From: "Jerry Keller (K3BZ)" <k3bz@verizon.net>
To: <>
Sent: Sunday, April 03, 2011 11:29 AM
Subject: Topband: Tower Shunt Feed
>I want to try a shunt feed on my 60' aluminum freestanding tower topped
>with
> a 4 element SteppIR. The tower is a Heights and it tilts over on a 4' high
> top-hinged base. I've come up with the following specs I dug out of K1ZM's
> book "DXing on the Edge": .....
.
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UR RST IS ... ... ..9 QSB QSB - hw? BK
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