At 12:33 PM 9/13/98 -0400, Bill Fisher, W4AN wrote:
>
>>The 40 M beam just begins to "work" at 100 feet and will work better at 125
>>ft.
>
>Disagree. I had a 402CD at 85' that worked GREAT. N4RJ's 40 meter yagis
>were 90' and I would stack his 40m signal against anyone's.
>
>I would say 75' is where the 40 meter beam starts to "work". But if you
>can get it higher... do it.
This is really a pretty fruitless debate, unless you define what "work"
means. There's no magical "knee in the curve" where a 40-meter antenna
suddenly acquires desirable characteristics. It's all a matter of what
angles are needed to do what you want to do, and how you can focus more of
your power at those angles, through a combination of antenna height and
foreground characteristics. I think that a 40 or 80 meter antenna can be
lower, in terms of wavelengths, for a given path than would be the case on
the higher frequencies, because the optimum angle of radiation for such a
path is higher on the lower frequencies. Good thing, considering how much
height costs, particularly for a big yagi.
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