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Old February 12th 11, 03:38 PM posted to rec.radio.shortwave
Joe from Kokomo[_2_] Joe from Kokomo[_2_] is offline
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First recorded activity by RadioBanter: May 2009
Posts: 952
Default Wire antennas again - counterweight question

On 2/11/2011 2:22 PM, bpnjensen wrote:
So, a mechanical question this time -

On a relatively short run of wire of fairly light weight (in this
case, 14 gauge stranded, insulated, and about 60-65 feet horizontal),
what's a good estimated counterweight for the far end? The wire
itself is light, but the counterweight needs to account for tension as
well. The support line is over a freewheeling pulley and is currently
tied off, but I think a modest eight would be better in this
circumstance as the near end of the line is a treetop with some sway
in the wind.

So, I ask if anybody has an idea about what a good weight night be to
maintain tension and avoid too much sagging. For starters, I was
thinking a simple barbell weight of 5 lbs or so more or less, but I'm
wide open on this one.

Thanks so much!
Bruce


Let me point you in a different direction...

When you ask about a weight, that implies you will also be using a
pulley (block, for you sailors). This is another piece to purchase and
another piece to rust up and fail, at least the hardware store
galvanized ones. Don't ask what the ones for sailboats cost.

I have had a 130 foot dipole (stranded 14 ga.) up between two trees
since 1994, with no failures here in the great Midwest (lots o' wind,
lots o' snow).

I considered the weight/pulley arrangement but ultimately decided on
using a screen door spring at each end. These are typically a foot (or
a little more) long and readily available at any hardware store. I would
recommend you pay a buck or two more and get the ones that are chrome
plated and then spray paint it too, for a little additional
weatherproofing (belt AND suspenders). Works fine, lasts a long time.