N3JNC 3 Element 2 meter Yagi Fox Hunting Beam

This antenna is very easy to build. Materials are some 1/2 inch aluminum tubing, 3 cold water pipe grounding clamps, 6 wing nuts, a 1/2 inch hose clamp, a cable TV ground block and a 75 ohm matching Transformer (This is just for the F threads to a solder stub and will be put into the ground block in place of the F81 (aka barrel).  A small piece of #14 copper wire, solder, and a small piece of hardwood dowel that has been lacquered to prevent moisture from turning the wood into a conductor.

This antenna is 75 ohm and I feed it with 75 ohm RG 59 CATV feed line. This goes to a BNC connector that attaches to my HT. My Kenwood HT has worked fine with it for 10 years. I get a good swr with this set up. Close to a 1:1.1, I have used it for receive and transmit for many years now. It probably has a better match than the HT's rubber duck.

If you are really worried about the match, I'll show you a gamma-match that I used on five element Yagi I built based on the same design as this antenna. The gamma-match will give you the 50 ohm feed point and works great.

But if you are using and HT, this will work fine.

 

 

Tools needed for this project will be a tubing cutter, wire snips, screw driver and a soldering iron.

* The driven element for the 75 Ohm version of this antenna is a dipole antenna with the ground side of the antenna being slightly longer than the center conductor side. The ground side of the dipole is bonded to the metal boom. The center conductor side is insulated from the rest of the antenna with a piece of lacquered hardwood dowel.

** The  driven element of the 50 Ohm version of this antenna would be one solid element insulated from the boom and fed with a gamma-match consisting of 3/8 inch tubing and stripped RG-8 using only the center conductor and dielectric going into the 3/8 inch tubing creating a capacitive coupling. You will see pictures of this in my article on my home brew 5 element Yagi.

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