In article ,
Bill wrote:
Wot's a TDR?

http://en.wikipedia.org/wiki/Time-domain_reflectometer

Ah - sort of know what that is but didn't know the name.



Invaluable for finding cable faults in large buildings and beyond.

I keep a simple one
http://www.norbain.co.uk/downloads/d...structions.PDF
for checking CCTV cabling and have used others on 100V line PA, I had
500m+ of cabling at an Open Golf course a few years ago that had gone
short and being in a hurry grabbed the nearest BT engineer and persuaded
him to lend me his TDR for a couple of minutes, it took me to within
feet of the cable. The inaccuracy was probably down to my pacing out of
the distance!

When my neighbours electric supply failed a few years ago the leccy
board opened up a joint in the pavement and TDR'd the underground cable
to his house and found the break within a foot of where they thought it
was, a brick used as infill 50 years before had finally damaged the
cable.

So all in all a very useful bit of kit.

I've got one of those things that sends an RF signal up a cable and you
trace it with a receiver. Was very useful on the one occasion I needed it.

But the ESR meter gets much more frequent use. ;-)

--
*If a thing is worth doing, wouldn't it have been done already?

Dave Plowman London SW
To e-mail, change noise into sound.