At 06:16 PM 10/11/98 EDT, AA4NC@aol.com wrote:
>
>I have a basic question about mounting dipoles (or inverted vees) on
towers. I
>have always used a PVC (insulated) standoff arm to get the feedpoint of
>dipoles several feet (usually 3'-5') away from the tower . I assumed that
this
>would help minimize interaction with other antennas on the tower, and
>basically be good all around. My dipoles usually worked pretty well done this
>way, even though it's more trouble mechanically.
>
>I wonder if anyone has done any modeling or has any evidence (anecdotal or
>otherwise) to show this method being better or worse than simply tying the
>center insulator a few inches off of the tower itself?
>
Hi Will -- Anecdotal only, but I had a 2-foot standoff supporting 40 and 80
IVs, which broke under tension one morning with a sound like a 30-30. Tied
antennas off to the tower with only a couple of inches spacing from it, and
they worked virtually the same in terms of SWR and mediocre performance.
With relatively wide-angle IVS, I suspect that the angle between the tower
and/or other antennas, being abt 45 degrees in either case, is enbough to
reduce interaction to a low level.
73, Pete Smith N4ZR
n4zr@contesting.com
"That's WEST Virginia. Thanks and 73"
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