Magnus A wrote:
>Now, reading more carefully on the package it says 15 Ohms/m resistance,
>another more (4 times) expensive roll has 2 Ohms/m resistance.
>Is this a piece of junk wire that would only work with a couple of KV in it
>to scare the cows away?
>I am thinking to make my beverage somewhere near 160m, that would be a
>resistance of a whole 2400 Ohms along the antenna.
>
>
>
I put this on EZNEC to look at what all that resistance does, compared
to using normal Beverage wire. I used a 160 meter Beverage that was
only 1 meter off the ground. On 160 meters, using the 15 ohm/m wire,
the gain loss at 30 degrees elevation was 5.5 dB and the F/B loss was
5.5 dB. That's a significant F/B loss for a Beverage that doesn't have
much F/B to start with. The beamwidth increased from 84 to 96 degrees.
On 80 meters the gain loss was about 7.5 dB and the F/B loss was 5.4 dB.
Using the 2 ohm/m wire, on 160 meters the gain loss was about 2 dB and
the F/B loss was nil. The beamwidth only increased by 0.6 degrees. On
80 meters the gain loss was about 1.8 dB and the F/B loss was nil.
Beamwidth change was nil.
The usual disclaimers about NEC's accuracy with wires close to the
ground apply, but maybe you can get an idea of what is going to happen.
I used Sommerfield-Norton average ground, and radials at the ends.
Jerry, K4SAV
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