Topband: Tower Shunt Feed

[K4IQJ]

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 at 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": .....
.