velocity factor, balanced line
Roy Lewallen Inscribed thus:
Bob wrote:
On Sun, 04 Apr 2010 20:38:35 +0100, Baron
wrote:
You could get a sample and measure it !
Well, I discarded that idea because I have no idea how.
But then, on a hunch, I checked the manual that came with my MFJ-269,
and sure enough, on page 34, it tells how to measure Velocity Factor,
utilizing the distance to fault mode. It'll take a day or so to
recharge the 269's batteries, and then I'll have at it.
Bob
k5qwg
Unfortunately, it's not really simple to make measurements with
symmetrical line. You'll be exciting a common mode current which will
travel with a different velocity factor and affect the measurement.
Roy Lewallen, W7EL
Please could you elaborate on how and why a common mode current has a
different VF on a balanced line.
--
Best Regards:
Baron.
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