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VK2ZRG > TECH 26.03.06 06:37l 35 Lines 1358 Bytes #999 (0) @ WW
BID : 2287_VK2ZRG
Read: DL1LCA GUEST
Subj: Re: HELIX.EXE
Path: DB0FHN<DB0RGB<DB0MRW<DK0WUE<7M3TJZ<JE7YGF<JN1ZPJ<VK7AX<VK2TGB<VK2IO<
VK2WI
Sent: 060326/0208Z @:VK2WI.#SYD.NSW.AUS.OC #:9881 [SYDNEY] FBB7 $:2287_VK2ZRG
From: VK2ZRG@VK2WI.#SYD.NSW.AUS.OC
To : TECH@WW
VK2ZRG/TPK 1.83d Msg #:2287 Date:26-03-06 Time:1:45Z
Andy wrote re my HELIX programme :-
>Scribble down the salient formulae and make a spreadsheet.
I included the King/Wong gain formula plus a corrected diameter/turns
formula (the formula in the ARRL book was wrong!) in the help/info pages
so anyone could do just that. The Kraus formulae are available from many
sources, and Dr Emerson's formulae may be obtained from his article which
can be downloaded from the W1GHZ web site (and possibly elsewhere).
My programme is built around these formulae and a gain/frequency curve
that I produced from data in the Antenna Engineering Handbook. So you
can write your spreadsheet/linux/windoze version if you want. I claim
copyright on my version so go do your own thing, and don't copy mine.
>Or just build a yagi instead ;-)
It's horses for courses Andy. A helical antenna has circular polarisation
and the dimensions aren't so critical; although for maximum gain the
dimensions do have to be just right. A properly designed and built yagi of
the same length will give you more gain. For linear polarised signals,
the yagi has a 3 dB gain advantage over a helical.
73s from Ralph VK2ZRG@VK2WI.#SYD.NSW.AUS.OC
Taglines by Colin Coker G4FCN
C Program run, C Program Crash...ReWrite in Pascal!
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