Its easy to use an MFJ-259 to quickly check cable loss, using its cable
loss mode. Its more accurate if you build or purchase a simple 50:75 ohm
broadband matching transformer.
The 259B uses 1/2 of open circuited return loss as transmission loss. This
only works if the line impedance matches the bridge impedance of the 259, so
it only works with 50 ohm lines.
75 ohm lines would need to be measured some other way. I have my network
analyzer set up to output files now, and eventually plan on measurements.
I'm too busy with work now, but someday in the not too distant future I want
to do that project.
I ran several tests, and the network analyzer (a real one, not a $500 one)
is by far the most accurate method and fairly easy to get data into
spreadsheets for processing.
73 Tom
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Topband Reflector
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