Six Meters – The Magic Band

Six meters, the “magic band”, has been researched and some of our results are given for an optimum antenna system for our little pistol station.  We currently have a M2 HO-LOOP Halo antenna at 22′.  Below is the first step of putting up a tower and raising an antenna to 50′.  We will explain how we came to the choice of that height. Our goal is to get it completed before the end of the 6 meter season and that’s getting very close.

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Wood instead of concrete for tower base.  This is a half way done picture.  The posts are 4 feet long and are shown buried half way.  Dirt will be filled in and only 6″ of cedar post will be above ground.  Seventy five dollars for wood versus the $1000 charge for concrete in the country.  The tower is one we at the old Parker remote which is a 30′ aluminum Universal Tower.  We plan to extend another 20 feet with aluminum tubing and put a 6 meter antenna at the top.  Work in progress.

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This is what the finished base looks like with wooden posts.  Ten year life expectancy in the arid Colorado plains climate.  By the way the wood posts insulate the tower from ground lending itself to being used as a vertical antenna as well.

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It’s up!  Complete with a Halo antenna and it seems to work well on the preliminary testing.  Stations came in with readings of minus 17 and minus 18 (FT8)  that KC0RF said he wasn’t decoding.  It totals 50 feet — 20 feet of mast above a 30 foot aluminum tower.  It was designed as a self-supported tower but it’s so old and weak it needs guy ropes so I can sleep at night.

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Upgrading

Adding a stacked halo should provide more gain and keep the radiation angle almost as low as it is with one antenna.  Per the manufacturer, M2, the additional gain is 4 db and the radiation angle is 6 degrees at the heights of 50 feet and 38 feet.  The phasing line, or power divider, is 75 ohms coax cut to electrical quarter wave length  and three-quarter wavelength.  Times Microwave makes a 75 ohm version of LMR400 for the cable tv industry and that is what is used here.  A 75 ohm bridge must be used to measure the lengths, not a MFJ-259 because it is 50 ohms only.

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