----Original Message Follows----
From: Pete Raymond <n4kw@infionline.net>
Subject: Re: [TowerTalk] Stepper Antennas and Shunt Feed Towers
Howard, That is very interesting as I would have thought that you would
want to use the Yagi as a capacity hat, and need to have the elements out
vice retracted. Course if your tower is tall enough for a full 1/4 wave
length then you do not need a capacity hat. What size tower do you have and
what freq do you have the tower shunt feed for?
73 Pete N4KW
Reply:
Pete and others,
I have an 80 ft tower with top 4 El at 82 ft and lower 4 at 40 ft. I use 2
separate shunt wires for 80 and 160. Actually, instead of wire I use 3/8th's
tubing which doesn't move much in the wind. I found extending the El's runs
my SWR up. I might possible be able to extend the El's and tune the
reactance out with the variable cap but have never tried it. Keeping the
elements retracted is an easyily repeatable position. My lower antenna is
rotated on a TicRing. I run the tubing inside the ring but outside the
tower. Where it passes through the Ring I wrap it with several layers of
Scotch 88. I use a gamma match with a vacuum variable. My SWR is less than
2:1 between 1805 and 1860 kHz with near unity at 1825.
Howard..K2HK
>__Don,
>I have had good results with a two stack of 4 element SteppIR's. I find I
>do
>best when all el's are retracted. No arcing noted.
>73,
>Howard..K2HK
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