Doc, You'll maybe even get a lobe of circular polarization, straight up, for
overhead HF satellite communications! As has been said, "You'll have to
model it!"
On a serious note, I believe 10 ft. separation with three tribanders,
regardless of direction, will have severe interaction because of the common
resonance's of the elements and relatively close proximity to each other.
I might suggest putting your favorite antenna at the top, at 65 ft. or maybe
a couple of feet more with a short mast and use the rotator, since there
certainly would be no gain advantages to your proposal. Its tough to beat a
single HF multiband antenna at 65-70 ft. for overall band flexibility and
good performance from a one tower station without rotating and phasing
stacks. three separate, and different tribanders spaced 10 ft. apart on the
same tower, aimed permanently in different directions sounds like nothing
but trouble issues to me.
73, -=Rog-K9RB=-
----- Original Message -----
From: "doc" <kd4e@verizon.net>
To: "TowerTalk" <towertalk@contesting.com>
Sent: Sunday, October 10, 2004 9:43 AM
Subject: Re: [TowerTalk] Three Fixed Tri-Band Beams on One Tower?
> This is, for the moment, a theoretical exercise.
>
> I am exploring the concept of reducing the potential points of
> failure and complexity. I do own a rotator. ;-)
>
> 10' is the separation number?
>
> So if I stagger the beams vertically, each with reflector close
> to the tower, 10 feet apart facing separate directions I should
> eliminate the interaction?
>
> This is more vertically efficient than 20 foot separation --
> necessary when the beam centers are in-line.
>
> So, how does this arrangement look:
>
> Northeast on a mast at 65'
> Southeast off the side at 55'
> South off the side at 45'
>
> I believe I have the necessary hardware to support the side-
> mount beams should I elect to do this.
>
> The strength issue of Rohn 25, Rohn 45, or Rohn 25 reinforced
> with a second Rohn 25 is a separate consideration.
>
> I also have a couple of 50' Rohn push-up poles on which I
> could mount fixed beams ... but that adds coax routing complexity
> and the push-up poles are much weaker.
>
> --
> Thanks! & 73, doc kd4e
> West Central Florida 100% Linux. Suse 9.1
> Drake, Hallicrafters, Heathkit, TenTec, Yaesu
> Radio Life: http://www.gospelcom.net/twr/
> Linux-Incompatible hardware is defective!
> USA Pres. Election 2004: http://www.rnc.org/
> ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> _______________________________________________
>
> See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless
Weather Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any
questions and ask for Sherman, W2FLA.
>
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>
_______________________________________________
See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless Weather
Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any questions
and ask for Sherman, W2FLA.
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