This is a result that might be shown by a cable that has sustained a lot of
damage, including crushing without shorting, corrosion, water invasion. What
frequency were the Z *Maximums* (odd-quarter wavelengths)? At the maximums
did the Z go really high, indicating a low loss to the short, or did it just
go up in the hundreds or something like that?
All bets are off on the VF of a severely damaged cable.
73, Guy.
----- Original Message -----
From: <ditzian@alltel.net>
To: <towertalk@contesting.com>
Sent: Tuesday, December 04, 2001 11:42 AM
Subject: [TowerTalk] MFJ-259B and Distance to Fault
>
> I have an MFJ-259B and I want to use it to measure Distance-to-
> Fault. I tried this, following the directions, and the coax in question
> showed that there was a fault at a distance far greater than the
> length of the coax, even after multiplying by Vf = .66.
>
> I then tried shorting out the end of the coax (center to braid), but I
> still read a distance to fault greater than the length of the coax.
> This distance is different from the one without the short.
> Furthermore, at different frequencies (that show an X crossing 0) I
> get different results, all distances greater than the length of the
> coax, with and without the short.
>
> Is a short at the end of the coax not equivalent to a fault?
>
>
> 73,
> Jan Ditzian
> KX2A
> kx2a@arrl.net
>
>
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>
> -----
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>
>
List Sponsored by AN Wireless: AN Wireless handles Rohn tower systems,
Trylon Titan towers, coax, hardline and more. Also check out our self
supporting towers up to 100 feet for under $1500!! http://www.anwireless.com
-----
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