JIMMIE wrote:
On Mar 10, 8:06 pm, "Bob M." wrote:
"Smitty Two" wrote in message

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In article ,
Oren wrote:
On Sun, 08 Mar 2009 12:03:07 -0700, Smitty Two
wrote:
I plan to buy a homeowner quality wire tracer. I see many available in
the $30 price range. Any particular brands or features to look for or
are they all pretty much the same? Any substantial reason to spend more?
Immediate use will be to trace de-energized AC wiring to see whether I
can restore operation to a few old outdoor lighting fixtures.
One brand is Fox and Hound.
Can you borrow a tester for a week/day?
Well, for the price point I'm considering, I'd just as soon buy one. I
don't mind owning tools. But if it turns out I need something expensive,
then borrowing makes sense, assuming the thing exists in my diminutive
personal network somewhere.
I think the challenge now is figuring out what I need. It could be that
the old light wiring is just hanging loose inside a breaker box
somewhere, but it could also have been cut and abandoned anywhere along
the way, so I might need something that can detect the wire from a fair
distance.
One thing that would be fun to use, but is nearly impossible to find, is a
"time domain reflectometer". A TDR measures the length of a wire by
connecting to one end of the wire. This would tell you how far away the
other end is, but it won't tell you where. Interestingly, it will also tell
you where the nicks and joints are in the line.

TDR's are highly specialized, very expensive pieces of equipment. Rental
houses won't have them and it's unlikely an electrician will either.- Hide quoted text -

- Show quoted text -

I hooked a TDR up to some house wiring one time and saw a lot of
little pips on the scree. I finally figure out what they were,
staples. On my TDR you have to tell it the kind of cable you are
testing to an accurate velocity length measurement. There is no data
for romex though I guess you could figure the velocity factor out by
testing a knwn length of cable.


Jimmie

What brand is it? We sold two old Tektronics 1502
units on eBay last year after rebuilding the battery
packs and fixing the chart recorder modules. The 1502
won't work on 120 volts AC unless a working battery
is installed, strange.

TDD