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Goodbye trapped antennas?

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Subject: Goodbye trapped antennas?
From: (
Date: Thu, 4 Jul 1996 14:15:44 -0400
In a message dated 96-07-04 10:04:55 EDT, you write:
>. What this exercise shows us, is
>that for the typical tribander on average lambdas of 0.25 to 0.6, we are not
>giving up significant gain by optimizing the spacings for 20 and tossing in
>an extra reflector for 10.. In fact, a number of the manufacturers have
>noticed this and use exactly that scheme... Given this, one can make the
>counter arguement to the independent, interlaced beams on one boom crowd,
>that THEIR designs which are not using all of the available boom on each
>band, are the compromise, not the traditional W3DZZ design... aaaand, the
>interlaced designs with all that tubing will have far more wind drag than
>traditional traps on a fewer number of elements....

Denny --

     Thanks for your elucidation on this topic. A bundle of compromises for
sure, design-wise but I see you point vis-a-vis the spacing. It still doesn't
address the TRAP problems (ohmic losses due to more connections, real loss of
a trap, etc.) that affect trapped antenna performance and efficiency.
>Further, if critical spacings on the interlaced designs is what makes them
>better than traditional designs, then we need to consider that they use very
>thin tubing in order to keep the weight and the the cost from becoming a
>government overrun program... This thin tubing wiggles around in the wind
>like a plate of spaghetti on a vibrator bed in a cheap motel... So much for
>critical spacing in anything other than a dead calm....How'd ja like them
apples? ...   :)

      As far as antenna wiggling, is it such a bad thing? Other than
"variable" spacing problems, it seems to me that the ability to 'shed' wind
forces is not such a bad deal. Bending rather than breaking seems reasonable.
As far as apples go, Washington State is the largest apple producing state
and I like 'em.

73,  Steve   K7LXC

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