Hi Clive
All I can do is give you real life results in stacking a 10 and 15 meter
monoband beam. I have a 5 element Hy-Gain ten meter beam stacked 9 feet
over a 5 element Hy-Gain 15 meter beam and no problems. I first put up the
ten meter beam and ran checks such as SWR and FB and used it for a while. I
then added the 15 meter beam right at the top of the tower and did the same.
All I can tell you is that the ten meter beam did not change any and seems
to work as well when it was up by itself. I have nothing to compare the 15
meter beam with because it was never up by itself. However, it feels right,
FB is good and SWR is fine. These antennas have been up for over ten years
and have had no problems. For what ever it is worth, this is the results I
had.
73 Gary
-----Original Message-----
From: Clive Penna <clive@gm3poi.prestel.co.uk>
To: TowerTalk <towertalk@contesting.com>
To: <towertalk@contesting.com>
Date: Monday, February 15, 1999 7:44 AM
Subject: [TowerTalk] Yagi Separation
>
>Hi, I'm currently trying to evaluate the effect of various spacings on a
15m
>4el and a 10m 4el. I wonder what others have found.? I have modelled both
>with each antenna being the upper one to see if the 15m screens more than
>the 10. So far it appears that the spacing has to be 10ft for a 1db
>degradation in the 10m Gain. so ideally 12ft. On putting the two antenna's
>at right angles they can be separated by 6ft without a gain drop off. Has
>anyone confirmed this?. I can't see the point of loosing the gain in a
lack
>of vertical spacing. So i'm minded to have them at right angles, any
>comments. Clive GM3POI
>
>
>
>
>--
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