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Old September 23rd 06, 03:41 PM posted to rec.radio.amateur.antenna
Danny Richardson Danny Richardson is offline
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First recorded activity by RadioBanter: Jul 2006
Posts: 115
Default Use of lattice line to feed dipole

On Sat, 23 Sep 2006 14:32:19 GMT, Cecil Moore
wrote:


Wow, from 0.2 dB to 0.4 dB. :-) Would the following
work for measuring the wet/dry losses of 1/2 wavelength
of ladder-line shorted at one end and an MFJ-259B on the
other end? Measure the resonant purely resistive impedance
at the open end. Wet the ladder-line and repeat the
procedure. Calculate the losses.

If the line were lossless, zero ohms would be read.
The deviation away from zero ohms yields the magnitude
of the loss in the line at the 1/2 wavelength resonant
frequency. That's about 8.8 MHz for 50 ft. of ladder-line.


You are assuming something that I am not. That is the measurements
were accurate. Measuring anything to a fraction of a dB is most
difficult - even with the best of equipment and mine was not.

Danny, K6MHE