I was really hopped up when I ran across the web site of G3TXQ. I was particularly hopped up by his documentation on his hexbeam experimentation, particularly the modified geometry broadband version.
I played around with my own experimental hexbeam for 17m/15m/10m, back in 2000-2001, right after I had re-licensed. There’s no magic to the antenna, but it does give one the performance of a 2 element yagi in a much smaller physical space. The hex design is right at the top of my “really interesting stuff” list. Its one of the things I corresponded with W4RNL over. ‘RNL was not a great fan of the design, but agreed that it did have its place. I’m not sure of the reason for my own illogical interest – just one of those things.
But back to G3TXQ. He has taken the step of modifying the geometry of the reflector. He indicates that this change will improve the f/b ratio and also gives a broad match that is closer to 50 ohms. The classic Hexbeam design has an impedence in the 20 to 25 ohm range. The G3TXQ version has a flat SWR across the 20m through 15m bands, and most of 10m. Way Cool. Even better, the modeling shows the best SWR and best f/b ratio seem to happen at approximately the same frequency.
I’m thinking about a 15m monoband version now. I guess its also time to go back and surf the hexbeam yahoo group again.
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