Why would moving the linear loading further out and having longer elements
change anything? Wouldn't it still be the electrical equivalent of a 1 1/2
wl dipole on 21 MHz?
----- Original Message -----
From: "Pete Smith" <n4zr@contesting.com>
To: <N2TK@arrl.net>; "'RICHARD BOYD'" <ke3q@msn.com>;
<towertalk@contesting.com>; "'Jose Castillo'" <N4BAA@cox.net>
Sent: Sunday, August 08, 2004 01:07
Subject: RE: [TowerTalk] STACKING
Yes, exactly, but the 240/230 doesn't use the N elements, so far as I
know. The N element antennas are much bigger and heavier.
73, Pete N4ZR
At 06:22 PM 8/7/2004, N2TK wrote:
>Pete,
>The MAG240N and EF240S seem to be two different type antennas. The "N"
>series has the linear loading moved out away from the boom.
>
>N2TK, Tony
>-----Original Message-----
>From: towertalk-bounces@contesting.com
>[mailto:towertalk-bounces@contesting.com]On Behalf Of Pete Smith
>Sent: Saturday, August 07, 2004 5:38 PM
>To: RICHARD BOYD; towertalk@contesting.com; Jose Castillo
>Subject: Re: [TowerTalk] STACKING
>
>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.
>
>_______________________________________________
>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.
_______________________________________________
TowerTalk mailing list
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk
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