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New Antenna



{{{Fred,
I'm curious how this antenna performs on UHF?
All the elements appear to be about 1/4 wave on 2m
and I dont see any taper to  shorter UHF elements?.

Presumably the elements are acting as 3/4 wave
elements on UHF, and I can understand how they
could be resonant, but I wonder how they can
also then have good forward gain, given that broadside
to a 3/4 wave antenna is usually not the peak gain direction.

But maybe you have come upon a working solution
that works "outside the box" of conventional thought
about log periodics and this could really be a neat
approach to dual band operation.

You ad mentions 9 dBi gain, but it does not specify
separate gains for VHF and UHF which usually are
different.  Can you clarify the two gains?
thanks.

Bob, WB4APR


Bob
   You are correct on the on the tripling effect off the uhf part of the
antenna.    When modeling it for Uhf it has two front pointing lobes at about
30 degrees off  from the main front lobe because the eliments should be at an
angle but this would be hard to manufacture.    I designed, tested it with the
help of Brock W6GMT.    He used it on the air and found it was compariable to
the Elk which he uses for portable operation.   I looked into the cheap yagi
design with an aluminum boom and it was suppior to the log design.    Brock
likes the log design because it does not require as close pointig as the cheap
yagi design and it does not need a diplexer.  Those who want to experiment
with the cheap yagi  and aluminum boom I used 3/4" square stock and found the
eliments needed to be about 3/8" longer on the  cheap   yagi   with metal
boom.    I   have a  metal   yagi    prototype for vhf made up if some wants
to experment I would be glad to ship it to to them for the postage.   My
antenna is electricly the same as the Elk with onley changes in eliment length
to copensate for differant materials that I used.   On the gain I got these
figures from the modoling program   Elk claims a 6 and 9 dbd gain.    The
Central States VHF/UHF is having a coliquim at the end of the month and I plan
on taking one and have it tested on the antenna test range

Fred
----
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