September 24th 09, 09:04 PM
posted to rec.radio.amateur.antenna
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First recorded activity by RadioBanter: Dec 2006
Posts: 1,169
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HELP WITH LADDER LINE CALCULATIONS.
Owen Duffy wrote in
:
....
Firstly, the formulae on the Wiki page that use the log term are
approximations of the function using the cosh term, and the
approximation is poor for small S/d.
Have a look at the calculator at
http://www.vk1od.net/calc/tl/twllc.htm , it uses the cosh term in its
calcs. BTW, the metric equivalent of your example is 2mm wires spaced
150mm.
cosh above should be acosh!
Owen
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