The answer is in W2PV's book--the number of elements is somewhat unimportant
compared to boom length. In his book, Jim Lawson pointed out that a .75
wavelength boom (54 feet on 20 meters) has almost the identical gain whether
you use 4, 5 or 6 elements. It pretty much all in the boom length.
Different number of elements gives you different levels of antenna coupling
for stacking and also presents mechanical differences such as weight and
balance and element position relative to the mast.
----- Original Message -----
From: "Richard Karlquist" <richard@karlquist.com>
To: "poster" <poster@gate.net>; <towertalk@contesting.com>
Sent: Wednesday, August 14, 2002 12:23 AM
Subject: RE: [Towertalk] What is the diffrence?
> While we are on the subject:
>
> Why is it that M2 uses
> 5 elements on 20 meters
> to get 8.1 dB gain but
> uses only 4 elements on 10 meters
> to get 8.0 dB gain? The
> booms are almost the same
> length, after you scale for
> wavelength (44 ft and 24 ft
> respectively). % bandwidth is
> almost the same too.
>
> Rick Karlquist N6RK
> richard@karlquist.com
> www.n6rk.com
> www.karlquist.com
>
> > -----Original Message-----
> > From: towertalk-admin@contesting.com
> > [mailto:towertalk-admin@contesting.com]On Behalf Of poster
> > Sent: Tuesday, August 13, 2002 6:44 PM
> > To: towertalk@contesting.com
> > Subject: [Towertalk] What is the diffrence?
> >
> >
> > Between the 5El KLM 20mtr monobander and the KLM Big stick 6El?
> > Is it just boom length and amout of elements?
> >
> > Jack
> >
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