Rick I resisted using my usual hokey sayings like "you can't have your cake
and eat it to on 80 meters", or "there is no free lunch with 80 meter
antennas". Getting the whole band, resonant, on 80 is just about impossible
with a fixed match. You could probably get it working with 2 parallel fixed
matches but it would be a real 'bear' getting it right. You will spend a
bunch of time modeling then getting the modeling to work in the real world
will still be even more time consuming. That is the main reason, especially
with 4 squares,(the original question in this thread), remote tuning units
are used.
Of course there is another alternative, which I use almost daily. I have a
single vertical which is resonant on 3795(middle of SSB DX window). It plays
really well and I more than hold my own. When I want to operate on CW I
simply ''''BRUTE-FORCE'''' power into the antenna by using the tuner in my
shack. It works well that way for both DX & Contests, of course not as well
as on SSB. I only run low power so there is no heating with the match at the
base. If you run a KW I would not recommend the ''''BRUTE-FORCE'''' method
unless you directly feed the vertical without a matching network.
73
MAL
N7MAL
BULLHEAD CITY, AZ
http://www.n7mal.com
Everyone in the world is
entitled to be burdened
by my opinion
----- Original Message -----
From: Rick Karlquist
To: N7mal
Cc: w8zn@comcast.net ; towertalk@contesting.com ; Richard Karlquist
Sent: Monday, March 16, 2009 22:57
Subject: Re: [TowerTalk] Bandwidth of a 1/4wl 80m vertical
N7mal wrote:
> There are several 4 square arrays in daily DX, and contesting, use in
> W6-land. They all (that I'm familiar with)operate both SSB and CW. They
> use
> tuning at the verticals to achieve both SSB & CW.
> 73
>
Yes, of course you can always retune to cover the band.
Maybe you didn't notice that I said "with a fixed match."
> From: Richard (Rick) Karlquist
>
> 2. No practical diameter is going to cover 3.5-4 MHz with a
> fixed match.
Rick N6RK
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