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Re: phasing two arrows



Hi,

Sorry it took a while to answer back.

Much like a turnstile, putting two dipoles in an X pattern causes them to
interact with each other, changing the impedance. In a turnstile, joining
the two dipoles with a 93 Ohm 1/4 wave section results in a 1.1:1 match.
However, Arrows are gamma matched, and that throws a bit of a curve ball
into the mix. 


Here is what I did. I took 2 Arrow antenna's and combined all the 2 meter
elements onto one boom. I did not do anything with 70cm elements except put
them back into the bag. Combining the 2 meter elements was very easy for
there are matching holes just below where they need to be. I cut a RG-62
1/4 wave section and connected to two driven elements, one via a T
connector. Done. I did not fiddle with the gamma match.

Resultant match was 1.8:1, not great, but acceptable. Jumped onto a Fuji
during  the Boy Scouts Jamboree on the Air and made a contact using my
FT-847 with power to spare.  

An easy experiment that anyone can duplicate with very minimal effort.

Warmest Regards,

Christopher Cox
KC8FRJ





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