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Topband: matching an inverted-L

To: <topband@contesting.com>
Subject: Topband: matching an inverted-L
From: sbertsch@lists.acs.ohio-state.edu (sbertsch@lists.acs.ohio-state.edu)
Date: Mon, 02 Dec 2002 15:58:09 -0500 (EST)

When I said 70' that was a typo, and may have caused some confusion.
I meant to say 170 feet. 

I have a 25' wooden pole at the back of the house. 10 AWG stranded,
insulated wire goes 25' up the pole on insulated standoffs, then the
remainder of the 170' (145') goes horizontal, through a tree, over
the barn, and ends at a dogbone with nylon rope tied to another tree
to hold up the far end.

So far I only have 8 130' radials. These, and two ground rods, are
bonded to a single-point ground plate just inside the basement wall.
RG-8, ground wires, and a 8-conductor control cable (CAT-5) run 
about 25 feet to the den/shack. There are 8 ferrite toroids, spaced
out, over this bundle of wires to help with common-mode noise. Under
the operating table, there is a copper box (homemade) with connectors
for these cables. The box also serves as a ground point for the shack,
I do not use the ground wire in the house wiring.

All in all, this is a good all band antenna. It's one of the quietest
I've put up, and hears very well.

The advice I've gotten so far has been to use an air variable cap,
possibly with a motor drive. I'd like to stick with my fixed capacitor
and relay idea for a reason I didn't mention: The TS-850 auto tuner
can handle everything above 160 meters, except for the low end of
80 meters; there I need a 10uH series inductance. Please, nobody
suggest I put a motorized roller inductor outside.

BTW, I tried a SGC tuner. It was quite happy with a 1.5 to 2 SWR.
I, however, was not happy, and neither was the rig. Sometimes the
dumb thing would find a low SWR but keep hunting and then settle
on a higher one. Off to ebay it goes.

Thanks again,
Steve K8ZG


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