I recall seeing a simple TDR as an "Idea for Design" in EDN or
some similar magazine.  It consisted, as I recall, of a pulse generator
that could generate a VERY SHORT pulse, and a series resistor that was
the same as the characteristic impedance of the cable.  In lieu of a very
short pulse, it seems that you could use a longer pulse (perhaps even a
square wave) with a very fast rise time.  You drive the cable with this
and watch the cable input with a scope.  After the end of the rise time,
you should be able to see the reflections.

Harold



Harold Hallikainen
harold@hallikainen.com
Hallikainen & Friends, Inc.
See the FCC Rules at http://hallikainen.com/FccRules and comments filed
in LPFM proceeding at http://hallikainen.com/lpfm


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