"philnyc" wrote in message
oups.com...
Jerry, thank you for your replay, kindly please forward the
instructions on how to build a turnstile antenna for 145 and 435 . Are
the arms 1/2 wave or 1/4 ?
Thanx again.
Phil
Phil
I havent persued this Cross concept with the intention of identifying
"just one way" of building an antenna. I dont mean to imply that my choice
was a good one. Maybe I should be more specific. I just havent yet
learned enough about how this "hemispherical pattern shaped" works. So far,
I've seen that 4 lambda over 2 dipoles can be nested into a slanted vertical
array to provide highly elyptical polarization thruout the hemisphere. It
is two pairs of crossed dipoles, each pair fed in phase and one pair fed 90
degrees later than the other.
I think the turnstile (with reflectors) has been described in many wer
sites. I could send you an accurate sketch of one, but you can surely get
better instructions from the Internet. Turnstiles are decent antennas for
hemispherical CP coverage and pretty easy to understand and build.
If you are definitely going to build an antenna from which you would
appreciate hemispherical elyptically polarized coverage, E-mail me. i
can/will help you understand either/both the turnstile and the Cross. I
wish I could help you understand the QHA or QFH helix antennas, they work
very well. But, I just dont have them figured out.
Jerry
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