Joe, I would urge your friend to look up the Force12 site which has a very
good write up on designing short Yagis. It may not be a specific design for
20m, but has a lot of useful information that would be handy to be armed
with. It was there that I learned that on a short Yagi the separation
between driven element and parasitic element resonant freqs are much lesser
than on monoband systems. This helped me with a 2el (loaded) wire yagi I
built sometime ago.
I have built quite a few shortened Yagis with mostly inductively loaded
elements (not the best!), but my next project would make me examine
capacitive and linear loading more closely. In the very recent past, I built
a capacitively loaded vertical which worked so very well that I am convinced
that I should make the second half and make it a vertical dipole! This
obviously is with the ultimate goal of making a Yagi!
I know this didn't answer you specific question, but hope the info on the
Force2 site would be of interest.
73,
Ron, 6Y5/4S7RO
----- Original Message -----
From: k7mks <k7mks@comcast.net>
To: <towertalk@contesting.com>
Cc: Dave Jackson <DavidJ1061@aol.com>
Sent: Tuesday, January 13, 2004 9:06 PM
Subject: [TowerTalk] Short 20m 2l Yagi
A friend of mine, Dave KA7GLI, is seeking comments, design info, for a 2
element shortened 20m yagi with a maximum element length of 18' for phone
band coverage. Neither of us has access to any computer design programs.
Would appreciate hearing from those who have successfully home-brewed a
shortened beam. Leads to published articles would be appreciated. Many
thanks, Joe k7mks
_______________________________________________
See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless
Weather Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any
questions and ask for Sherman, W2FLA.
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_______________________________________________
See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless Weather
Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any questions
and ask for Sherman, W2FLA.
_______________________________________________
TowerTalk mailing list
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