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Old October 13th 14, 03:12 PM posted to rec.radio.amateur.antenna
Ralph Mowery Ralph Mowery is offline
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First recorded activity by RadioBanter: Jul 2006
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Default OK, let's discuss dipoles vs length


"Lostgallifreyan" wrote in message
. ..
"Ralph Mowery" wrote in
:

Looking at a chart in an old ARRL antenna handbook gives a rough
estiment of a length of 500 feet and a tension of 400 pounds a wire of
around 12 to 14 gauge will drop about 10 feet if Idid it right.


That's useful. Thanks. Did they say what metal it was? I'm guessign hard
drawn copper but if not it may be harder to adjust reckoning for something
else.


They gave two types. Hard drawn copper and copper coated steel. The only
differance would be the weight of the wire and how much tension you can put
on the wire before reaching the breaking point. The type of wire does not
matter, just the weight and how much tension you can put on it before it
breaks. Really how much tension you can put on the wire with a large safety
factor. Probaly less than half its actual breaking tension. I know that
Rohn towers specifies about 10 % for their guy cables. That is for the 4000
breaking of 3/16 cable they recommend 400 pounds of tension on the guy
cables.

Here is an on line calculator that will give you the answer to your
question.
http://www.spaceagecontrol.com/calccabl.htm

It seems for the first part you devide the tension of the wire by the number
of feet between supports.
For the 3rd part you devide the total weight of the wire by the length.




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