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Old June 5th 04, 03:50 PM
Tyas_MT
 
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"Richard" wrote in message
...
Is anyone engaged is a design philosophy that seeks the design of VHF

yagi's
with the smallest acceptable diameter of elements?

What you are trying to do is to design lighweight VHF yagis, you are

seeking
how small you can go with element diameters before performance begins to
suffer.

The performance that suffers (afaik) from smaller antenna elements is a
small lowering of the 'bandwidth' of the antenna, and maybe a small change
in the 1:1 swr tuning point. Mind you I'm not an expert on Yagi antennas

I built, for a 'start from scratch' foxhunt, a 3 element yagi on 2m (~146
mhz) out of magnet wire glued onto a piece of poster board. I used standard
numbers and it worked fine. The hardest part was soldering wire thinner than
my hair to the coax and anchoring the coax to the poster board so it would
get pulled off.
I won the hunt over all the 'body shielded ht' guys, even taking 10min to
build my antenna...


Later that week I used it to call into a net on a local repeater, so it
handled 15 watts without anything melting.

Much more critical on a Yagi are element spacings (directivity and
Front:back ratios) and lengths (resonant frequency).