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Re: Topband: Quarter wave sloper ?

To: "jim.thom jim.thom@telus.net" <jim.thom@telus.net>, Felipe J. Hernández <np4zet@gmail.com>
Subject: Re: Topband: Quarter wave sloper ?
From: Rick Kunath via Topband <topband@contesting.com>
Reply-to: Rick Kunath <k9ao@yahoo.com>
Date: Sat, 27 Jul 2024 17:12:30 -0400
List-post: <mailto:topband@contesting.com>
Jim, I forgot to mention that 90 or 100 feet is plenty of separation for a phased flag array made of two un-terminated flags mounted vertically

I made a cheap water drill to mount mine and PVC pipe goes into the ground like butter and cements tight almost immediately. I droverr a 1 1/2 x 10-foot PVC pipe 5-feet into the ground and then a couopling and another 10-foot section on top. That's enough to get the bottom wire of the flag at about 4 feet from the ground and it works well. But as a note, paint the top pipe black before you put it up to make it disappear from view. White shows up pretty well. Black doesn't.//The bottom part and the coupling is easy enough to reach to paint from the ground. /
/
If you wanted to you could terminate the bottom corner opposite the feedpoint, either adjusting that and then making up a fixed resistor pack or using a VACTROL to make it remote adjustable, but I find my ability to move the null where I want it is great without the termination and loss of bi-directionality and the additional 30 dB loss with termination so you need a preamp at each loop. Unterminated you don't need the preamp./
/
Rick Kunath, K9AO
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