I have found over the years that if you can not put it up at least 1/4 wave
above ground for testing/adjusting clear of other objects, it is better to
support the antenna in a way that it stands on the reflector and points slyward.
This works very well, and can be done by tying a rope between two trees or other
items, and throwing a second rope over it in a clear area. Tie the second rope
to the director end and raise the antenna to "near" vertical. This works well on
all antennas, except Logs. Your SWR will be within .1 and .2 of what it will be
at the top of the tower.
Joe Natale wrote:
> I just built the A4S/A744 Cushcraft 4 el tribander with 40m kit. I built it
> on a mast about 4' above the ground using the band center dimensions. The
> 1:1 SWR points are: 6.9, 14.050, 21.3 and 28.7. Do I tune it to resonance at
> it's present position 4' above ground or put it up on the tower as is and
> take my chances? It is going to be at the top of a 72' aluminum tower. The
> manual is very vague on these issues. This is my first beam and can use your
> advice. Thanks in advance.
>
> --
> FAQ on WWW: http://www.contesting.com/towertalkfaq.html
> Submissions: towertalk@contesting.com
> Administrative requests: towertalk-REQUEST@contesting.com
> Problems: owner-towertalk@contesting.com
> Search: http://www.contesting.com/km9p/search.htm
>
--
-------------------------------------------------------------
Bruce Richards / WD4NGB (No Good Bum)
50 miles Northwest of Nashville Tn.
DX Web Page http://home.sprynet.com/sprynet/wd4ngb
Space A DX Group http//www.geocities.com/Nashville/9846
--
FAQ on WWW: http://www.contesting.com/towertalkfaq.html
Submissions: towertalk@contesting.com
Administrative requests: towertalk-REQUEST@contesting.com
Problems: owner-towertalk@contesting.com
Search: http://www.contesting.com/km9p/search.htm
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