You can determine loss fairly closely with a decent vswr measurement. If
you can disconnect or short the coax at the far end, the vswr measurement can
be converted to return loss and actual loss is one half of the return loss
value.
If opening/shorting the coax is a problem, you can still make less accurate
measurements by running the test on a frequency that causes a high vswr on
the coax. The higher the test frequency, the higher the loss and more
accurate loss predictions.
Once you get a decent measurement, the info can be scaled to other
frequencies by a factor of 3 X freq = 2 X loss.
73,
Gerald K5GW
In a message dated 8/27/2010 9:34:58 A.M. Central Daylight Time,
n4zr@contesting.com writes:
What is a good working rule for the life expectancy of decent quality
RG-213? I have a lot of it around here, and it is difficult to measure
loss in situ. Jackets still seem fine, but wonder if it's time to
replace before winter.
--
73, Pete N4ZR
The World Contest Station Database, updated daily at
www.conteststations.com
The Reverse Beacon Network at http://reversebeacon.net, blog at
reversebeacon.blogspot.com,
spots at telnet.reversebeacon.net, port 7000
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