With a short circuit termination, the line needs to be an even number of
quarter-waves long; with an open termination the line needs to be an odd
number of quarter-waves long.
For the short-circuit termination case, measure the input resistance Rin
at a frequency where the line is an even number of quarter-waves long;
then a close approximation to the loss is:
Loss (dB) = 8.69 x Rin / Zo
Take a look at measurements made using that method compared to
predictions in the final chart here:
http://www.karinya.net/g3txq/wet_ll/
Steve G3TXQ
On 12/08/2016 19:53, TexasRF--- via TowerTalk wrote:
And the results are intuitively obvious for even the most casual observer,
right?
The pdf mentions 1/4 and 1/8 wavelength multiples. Can we take it that
random lengths do not work for the concept?
73,
Gerald K5GW
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