Towertalk
[Top] [All Lists]

Re: [TowerTalk] Stacking Tribanders

To: Ron WV4P <wv4ptn@gmail.com>
Subject: Re: [TowerTalk] Stacking Tribanders
From: David Gilbert <ab7echo@gmail.com>
Date: Tue, 21 Jun 2022 13:48:55 -0700
List-post: <mailto:towertalk@contesting.com>


That's just plain wrong.  That's using HFTA to determine optimum height above ground ... not optimum stacking distance (i.e., separation).  They are NOT the same thing.  HFTA does NOT properly calculate anything based upon stacking separation.

Dave   AB7E



On 6/21/2022 11:23 AM, Ron WV4P wrote:
HFTA should Always be used to try to optimize stacking distance.
 It shows the nulls and enhancements created by Your Terrain, and how to exploit and or cover them. Then you can use another program, like EZNEC to calculate the stacking gain as a function of stacking distance based on the HFTA data.

One without the other is a waste of time.

HFTA tells you where to put the antennas.
EZNEC tells you what antennas to put there.

Ron, WV4P

On Tue, Jun 21, 2022 at 1:00 PM David Gilbert <ab7echo@gmail.com> wrote:


    HFTA should never be used to try to optimize stacking distance.  It
    simply does not actually calculate the stacking gain as a function of
    stacking distance like EZNEC would.

    73,
    Dave   AB7E



    On 6/21/2022 10:34 AM, sawyered@earthlink.net wrote:
    > HFTA kinda sorta calculates stacking properly.  It seems to
    assume you get
    > the optimum 2.7db stacking gain whether the spacing is optimum
    or not.  And
    > it draws the HFTA ray from the center point between the 2.  So
    it would
    > calculate a 2 high stack of 20M yagis having an added 2.7db of
    gain even if
    > they are stacked only 20 ft apart and will draw the enhanced ray
    from the
    > midpoint between the 2 yagis.
    >
    >
    >
    > Ed
    >
    > _______________________________________________
    >
    >
    >
    > _______________________________________________
    > TowerTalk mailing list
    > TowerTalk@contesting.com
    > http://lists.contesting.com/mailman/listinfo/towertalk

    _______________________________________________



    _______________________________________________
    TowerTalk mailing list
    TowerTalk@contesting.com
    http://lists.contesting.com/mailman/listinfo/towertalk

_______________________________________________



_______________________________________________
TowerTalk mailing list
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk
<Prev in Thread] Current Thread [Next in Thread>