Hello,
After my 4th quad in 40 years, this last one covers from 30M to 6M.
It is a spider type design, with optimum element spacing.
I found with this last one, with all the WARC bands, it seems to lower the
impedance.
I found them closer to 70 ohms not 90, and removed all the matching
sections. I used a tower
mounted coaxial switch. The match is quite good without matching sections.
73's
Glen K4KV
Tom
I think that you need to know the impedance of your antenna first before
think
to use a matching section to adjust it to your coaxial.
I have a 6 band quad 6-20m and only in 12m is needed the matching section
all
the others bands are direct feed to 50 ohms
the antenna design was to have the direct feed to 50 ohms coax, the
impedance
is around 45-60 ohms in the bands and most of them reach the 1:1.1
each loop is feed with a piece of coaxial cable to the remote antenna
selector.
More info about my antenna that was designed by Robert KG6B (I took
advantage
of his work and build mine first ) he have a photo of his antenna and
all the related things in his web page http://www.kg6b.com/
I have another 6m quad old design and that also feed direct to 50 ohms,
from
the packet.com
Another great source of Quads mono band and long boom are in the W4RLN
books
Cubical Quad.
Also a few clues of how you can get a direct feed to 50 ohms with broadband
in
quads (yagis also) is www.g0ksc.co.uk he is great in the design and
modeling antennas
Hope you learn a few new things of the quads modeled with powerful computer
software.
J.Hector Garcia XE2K / AD6D
Mexicali B.C DM22fp
P.O.Box 73
El Centro CA 92244-0073
http://xe2k.net
http://dxxe.org
________________________________
From: Tom Horton <k5iid@sbcglobal.net>
To: antennas@mailman.qth.net; Tower Talk <towertalk@contesting.com>;
ctdxcc@kkn.net; ntcc@yahoogroups.com; ham-antennas@yahoogroups.com
Sent: Mon, November 8, 2010 8:41:16 PM
Subject: [TowerTalk] Quads
I've been using Quads for many (50+) years. Previously I have always used
1/4
wave matching transformers.
But this time when it went up, I purchased a commercial matching
transformer.
Well, when it was installed, it was open. So, for a temporary fix, the 20
and 17
meter elements were attached to the feedline directly. The antenna seems to
perform quite well even in this hookup.
I am tempted to just hook all the elemments to the feedline without a
matching
device of any kind.
I have read many things written about doing this and it seems that all seem
to
have favorable results.
I am interested in hearing from fellows that have done this and what their
results were.
Thanks,
Tom K5IID
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