Re: [TowerTalk] STACKING

[Pete Smith <n4zr@contesting.com>]

The 240 part of the F12 antenna is, I believe, the same as an EF-240S.  At 
6 foot spacing from my top tribander, I had to turn my EF-240S 90 degrees 
to prevent significantly affecting the SWR of my F12 tribander on 
15.  Advice from Force 12 was at least 12 feet spacing, but each unique 
combination of antennas brings its own set of problems.

73, Pete N4ZR

At 02:53 PM 8/7/2004, RICHARD BOYD wrote:

> As I often do, quoting others more expert than myself, the main issue seems
> to be detuning of the 15M yagi by the 40M yagi.  I asked W3LPL how far a 15
> and a 40 should be apart.  He thought 30' would be good.
>
> Most of us would not be able to get that much distance and still have them
> both rotating on a mast at the top.  One of them would either have to be
> sidemounted lower down the tower, or you have to accept the potential for
> degradation of performance by having them closer.
>
> In the real world, many people put their tribander and 2-el 40 within a few
> feet of each other and are satisfied with the performance.  Obviously, more
> is better.  While it's a different situation, different bands, I have 20 and
> 15 yagis 8' apart and they've always worked well.  It's the
> interaction/degradation problem that causes people to pair 40/10 and 20/15
> on two towers -- alternatively, 40/20 and 15/10.  But not 40/15 together.
> With a tribander for 20/15/10 that's not the situation you have.  15 is the
> one that suffers, typically.
>
> Probably 6-8-10' separation between the tribander and 40 is worth a try and
> see if it works satisfactorily for you.  The resonant point and/or pattern
> of the 15 may change.
>
> You might try putting up the tribander first and do good performance plots
> across each of the three bands.  Then put up the 40 at whatever separation
> you can achieve and repeat the plots to see what effects you can observe.
>
> 73 - Rich, KE3Q
>
>
> ----- Original Message -----
> From: "Jose Castillo" <N4BAA@cox.net>
> To: <towertalk@contesting.com>
> Sent: Thursday, August 05, 2004 7:54 PM
> Subject: [TowerTalk] STACKING
>
>
> > Hello,
> > I am planning on purchasing a SteppIR 4 element yagi.
> > I also have a Force 12 240/230 (2 ele on 40 and 30 meters)
> >
> > How high above the SteppIR would be adequate?
> >
> > 73
> > Jose - N4BAA and YI9BAA
> >
> > _______________________________________________
> >
> > 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.
> >
> > _______________________________________________
> > TowerTalk mailing list
> > TowerTalk@contesting.com
> > http://lists.contesting.com/mailman/listinfo/towertalk
> >
> _______________________________________________
>
> 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.
>
> _______________________________________________
> TowerTalk mailing list
> TowerTalk@contesting.com
> http://lists.contesting.com/mailman/listinfo/towertalk

_______________________________________________

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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