-----Original Message-----
>From: Lee Buller <k0wa@swbell.net>
>Sent: Oct 15, 2008 9:55 AM
>To: Bob Ortasic <rortasic@neo.rr.com>, TowerTalk Reflector
><towertalk@contesting.com>
>Subject: Re: [TowerTalk] Th6dxx swr
>
>Bob,
>
>I set the ones I have used for mid-band. That gave me the best band coverage
>on 20-15-10. Make sure you waterproof the traps. The balun should be good.
>
>That low to the ground you will not get a good reading. As the other feller
>said....stand it up on the reflector vertically. Watch out for overhead wires.
>
>Lee - K0WA
>
I did some NEC4 modeling of the effects..
See http://home.earthlink.net/~w6rmk/antenna/yagiht.htm
Resonant frequencies change by about 100kHz for a 20m 3 element yagi, comparing
between 70ft and 6ft off the ground. Pointing it up helps, soil properties
also change the effect.
Jim, W6RMK
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