Tune Around!

2 Element Wire Beam for 28 and 24 MHz
by John Reisenauer, Jr. KL7JR/KL7USI/K7ICE

This is an experimental antenna project- feedback appreciated!

Here's a very simple antenna to build which only requires two supports and is easy to install. The only cost is some wire and rope plus PVC scrap for the insulators!

Just build, lay out on the ground and hoist up in the air! No coils or fancy matching networks required. You may want to use a balun at the feedpoint.
If you put up two aimed in opposite directions, you should get a somewhat stretched out bi-directional pattern much like two circles end to end as viewed from above, or just use one to zero in on a specific direction. After all, it is a beam!

A two element Yagi will have a gain of about 3 to 4 dBd and have a driven element with either a reflector or a director. The reflector is about 5% longer than the driven element with the driven element nearest the receiving station or use the driven element with a director that is about 5% shorter than the driven element with the director nearest the receiving station.  Either way you use it, it should provide substantial gain over a standard dipole!
Using the N3DNO antenna calculator we arrive at the following dimensions for the design frequency of 26.7 MHz (midpoint of 10 and 12 meters):

Driven Element---- 8 feet and 10 1/4 inches per side (17'-8 1/2" total)
Reflector---- 18 feet 9 1/4 inches total length
Spacing----7 feet 2 inches


Some experimenting and a tuner will be required. I have not tried this design yet.

The dimensions should be good starting points. You can add a Director (16'-8" long and use same spacing of 7'-2") for a 3 element version to get about 5 -7 dBd gain!
 Not bad for some wire, a few pieces of PVC and a little fun in experimenting!
Any and all feedback is appreciated.
KL7JR@YAHOO.COM

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