Al,
The stacking distance for this antenna will depend on the active section
of the boom for each band.
Assuming the 20m section is the longest lets go from there.
Figure the boom length in Wavelengths for the 20m section 15m section
and 10m section.
The optimum stacking distance in Wavelengths will be the Square root of
the Boom length of the section in Wavelengths.
All of this stuff can be found in the application notes section of my
website on stacking yagis.
What happens with these multibanders is you will have to make a
compromise. Usually its putting them at .5 WL apart at 20m that will be
.75 WL apart on 15M and 1 WL apart on 10m.
Knowing a little about the design of the 5BA I will think you will find
30 feet to be optimium so you 37 ft choice is the right compromise. 57
is way too long unless you have a 48 foot 20m section. Hi
Jay
Al Williams wrote:
>
> This 5BA suggestion is very timely for me as I have all but settled on two
> of them.
>
> However, should it be considered a long boom antenna(s)? If the drawing in
> the catalog is
> somewhat to scale, it appears each antenna occupies less than half the boom
> length i.e.
> less than 16 feet?
>
> I will mount one 5BA at the top of a chrome mast on a crankup Triex LM470
> at about 83'.
> Should the second 5BA be mounted at 37' or 55" (top of the second and third
> sections)?
>
> Does anyone have the 5BA modeled for EZNEC?
>
> thanks
> k7puc
>
> ----- Original Message -----
> From: <n4kg@juno.com>
> To: <TOWERTALK@contesting.com>; <poster@gate.net>
> Sent: Friday, January 26, 2001 4:32 AM
> Subject: Re: [TowerTalk] Wish Force12 made the C51XR with 12,17 and 30mtrs
>
> > The Force 12 5BA covers 10, 12, 15, 17, 20 meters
> > on a fairly long boom (see catalog). They also have
> > some WARC band beams.
> >
> > For those who want higher gain than typical tribanders
> > provide, the long boom Force 12 tribanders and a separate
> > antenna for the WARC bands is a better way to go.
> >
>
> --
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--
Jay Terleski
WX0B - Array Solutions
Phased Arrays - Horizontal and Vertical
RF Switches, Antennas, Towers
www.arraysolutions.com
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