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Support for wire antennas. Wire or rope?

Jan 25th, 06:19

N1AUP

Joined: Apr 4th 1998, 00:00
Total Topics: 0
Total Posts: 0
Let's say I decide to hang a dipole. I use something to tie the dipole to a tree. That connects to an insulator, which connects to one radiating side of the antenna. That radiating side attaches to another insulator, which then connects to the physical support part of the balun or center insulator. A lead wire connects the electrical part of the balun to that radiating element. The design repeats on the other side. You also have something tying the balun to a support.

Is there any reason not to use wire for the supporting parts? Or is having that small amount of metal going to cause problems?

I'm concerned about using rope for support parts because it will degrade and drop the antenna.

Thanks
Jan 25th, 15:03

W1VT

Joined: Apr 4th 1998, 00:00
Total Topics: 0
Total Posts: 0
Antenna modeling is the only practical way to see the effect of a support wire on a dipole. The math is too hard to enable any useful calculations based on first principle equations.

But, based on my modeling experience with half wave dipoles at the often low heights used by hams, the effect is likely to be negligible. And when you look at harmonic operation the effect is too unpredictable to waste the time trying to figure it out. Like an 80 meter dipole used on 10 meters with 100 feet of low loss ladder line. It is what it is.

Zak W1VT
ARRL Senior Lab Engineer
Jan 25th, 17:37

N1AUP

Joined: Apr 4th 1998, 00:00
Total Topics: 0
Total Posts: 0
Thank you for answering both questions. First rate!

Chris

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