On Tue, 09 Oct 2012 12:06:43 -0500, John S
wrote:

On 10/9/2012 11:10 AM, Jeff Liebermann wrote:

I still use a home made TDR (time domain reflectometer) for testing
cables. Old habits and methods die slowly.

Do you have any construction information available for your TDR?

I actually have serveral. All you need is a pulse generator and a
decent oscilloscope. Pulse width and frequency will depend on the
length of coax cable you're trying to test.

These designs work well:
http://www.epanorama.net/circuits/tdr.html
http://www.fccps.cz/download/adv/frr/Reflectoprobe/reflectoprobe.html

This one is similar, but in my never humble opinion, not as good as
the previous one.
http://www.mouthmusic.com/TEMP/aa6dd/Time_Domain_Reflectometer.jpg

Mo
http://www.ecnmag.com/articles/2009/07/low-cost-high-resolution-time-measurement-application
http://www.youtube.com/watch?v=jOUhg07N2-U
http://www.youtube.com/watch?v=Il_eju4D_TM
etc.

Also look on eBay for a Tekronix 1502, 1503c or similar TDR.

--
Jeff Liebermann
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558