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Re: [TowerTalk] Looking for thoughts

Subject: Re: [TowerTalk] Looking for thoughts
From: Jim Brown <>
Date: Mon, 06 Aug 2012 20:30:00 -0700
List-post: <">>
On 8/6/2012 2:40 PM, K1TTT wrote:
> I would use a decent low loss coax, a remote relay box, and keep the tuner
> in the shack.

I strongly agree.  In addition to switching antennas with relays, you 
might also consider designing some stub matching networks that you also 
switch in and out. You've got that new antenna analyzer, and it will 
write S1P or S2P files. Measure data for each of your antennas, then 
export it to SimSmith, then move along the line the antenna, then back 
down the line to a point where you can insert a stub.  I'm currently 
implementing exactly that strategy, replacing multiple manual antenna 
tuners with switched stubs.

SimSmith is freeware that runs in Java.  Very nice, very user friendly.

Depending on how long your lines are you might also want to consider 
finding some used hard line. The run to the top of my tower is 350 ft, 
and I've  been feeding it with a combination of 1/2-in and 7/8 line that 
I pieced together from a neighbor's estate.

  I recently acquired several pieces of 1/2-inch and 7/8-in 50 ohm line, 
and have been finding and installing connectors to fit them. So far, 
every piece has looked good when I swept it to 500 MHz.  One piece of 
7/8-in showed a small bump that turned out to be a small pinch in one 
side the shield. If I were going to run 50kW through it, I'd be 
concerned, but at ham power levels on the HF bands and 6M it will be 
just fine!  By the time I'm done, I expect to pick up about 1 dB on 6M, 
about half that on 10 and 15.

73, Jim K9YC

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