>
>
>-----Original Message-----
>From: 2 [mailto:2@vc.net]
>Sent: 27 July 2002 16:04
>To: g0ruz@btinternet.com
>Subject: RE: [Amps] Muffin Fan on Swan Mark 1
>
>
>>Sure but fwd gain is important in moonbounce. The trouble with computer
>>apps is that are created by humans.
>
>Ahh now there's where you are wrong, what is important in eme is G/T which
>is a combination of gain and antenna noise temperature, these days noise
>temperature optimisation is what gives you the best performance on the eme
>circuit. Of course the best yagis have excellent gain coupled with a very
>clean pattern and all of them have been computer optimised. In this case
>computer optimisation works really well and of course the test range and the
>eme path prove it. I totally agree however that it computer modelling is a
>poor substitute for the real thing. In the case of yagis had Yagi-Uda not
>given DL6WU something to start on we would be nowhere. DL6WU used the test
>range to "tweak" his antennas and then DJ9BV,K6MYC etc took the DL6WU and
>really optimised it, this saved many hours and lots of metal. I doubt very
>much whether we will improve the yagi any further.
>I have been on 144 and 432 eme since 1990 BTW.
Interesting. thanks.
About 20-years ago, John McDonald, W6SDM built an 11-el 432MHz yagi-uda
with adjustable matching, element length, and spacing on a non-conductive
boom. He tried the various publish designs. He arrived experimentally
at optimal gain compared to an NBS reference antenna. My guess is that
was little room left for improvement.
cheers, Conrad
- R. L. Measures, a.k.a. Rich..., 805.386.3734,AG6K,
www.vcnet.com/measures.
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