I participated in a phone multi-multi operation in my youth using
a triband quad with separate feedlines. Rather than proper filters,
we were using coaxial stubs. There was also a very nice looking
army surplus low pass filter with a cut-off frequency of about 21
MHz for 20 M. Sadly, 20 M still got a lot of garbage from the
other two bands, and 15 M had a little bit of trouble from 10 M.
The feedlines were equipped with baluns -- air wound trifilar 1:1
baluns as I recall -- and though they were dressed down the
boom together, after going through the turning loop at the bottom
of the mast they fanned out to reduce coupling.
----- Original Message -----
From: "Alfred Frugoli" <ke1fo@arrl.net>
To: "CQcontest Reflector" <cq-contest@contesting.com>
Sent: Wednesday, February 13, 2008 10:31 AM
Subject: [CQ-Contest] Quads and SO2R
> Hello fellow contesters,
>
> In the recent NCJ article by K0SR about Quad construction, he mentions
> that
> the best way to feed a quad is to feed each band independently and use a
> switch mounted on the mast to select bands. Has anybody used a triband
> quad
> on 2 bands simultaneously (obviously with proper filtering)?
> _______________________________________________
> CQ-Contest mailing list
> CQ-Contest@contesting.com
> http://lists.contesting.com/mailman/listinfo/cq-contest
>
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