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Re: New Antenna



Fred,

Have you looked at adding a 1/4 wave uhf element on the opposite 
side of the feedline/boom from the vhf element. It would create 
open stub j-poles at uhf so you would have two end fed 1/2 waves 
spaced a half wave apart at uhf. I think this was a common 
alternative to the Vee LPD for TV.

Mike

> 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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