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Re: The QHA antenna.



Steve, John, & the BB,
Yeah, Steve, we all need another project to keep us busy--hi.

I've looked at that design, even that particular page, and several others and
have not thought the QHA would be that easy to build.  This one does appear
simpler than the more common coax-element ones.  I'm really glad to hear
several people say they have done it and it wasn't overly difficult.  Even
Martin, KB2UC, favorably reviews it in his books.  I have been working over
the last several months on a couple of different designs trying to find that
elusive "perfect" omni antenna.  Maybe it's been there all along and I was
just too thick-headed to pay attention.  I usually build a 70 cm prototype
first since I can easily use the FO-20/29 downlinks as my test range.  I
recently had a dismal failure of a design I spend several weeks modeling and
perfecting, only to determine it was far inferior to an eggbeater (my standard
reference antenna) in actual use.  Even field-strength measurements defy my
computer models!  I'm begining to suspect the computers are plotting against
me :-)

Sorry to be so long-winded, what I really wanted to know is why the scaling to
70 cm was a problem.  Is it the thickness of the elements?  Has anyone out
there built a 70 cm QHA and used it for mode J downlink?  Let us know.

73, Jerry
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