As Gerald says, get the books. It's not so many feet just because it's 6
meters. My feeble brain remembers them talking about wavelength and boom length.
TexasRF@aol.com wrote:
> In general, as the stacking distance exceeds optimum, the mail lobe
> beamwidth continues to deacrease. The gain does not increase as one might
> expect
> because the grating lobe amplitude increases and "eats" the extra apparent
> gain
> associated with the narrower main lobe.
>
> At 144Hz and higher frequency, the added grating lobe amplitude can hurt
> receive s/n if the lobe sees a noisy power source such as man made noise or
> sky
> noise from our galactic center.
>
> At 50MHz and lower, the background noise is so high that it makes little
> difference if the grating lobes see these noise sources.
>
> There are complete chapters and books to read all about this and a good
> starting point is one of the VHF/UHF manuals if you can find one (all the
> ARRL
> manuals are out of print).
>
> 73,
> Gerald K5GW
>
>
>
> In a message dated 1/2/2009 3:31:44 P.M. Central Standard Time,
> k9kl@centurytel.net writes:
>
> What happens to an antennas pattern
>
>
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