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Interconnects, speaker wire, power cords. Ask the Cable Guys.

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Time Domain Reflectometry ?

Posted by tonemaniac on April 13, 2006 at 06:36:48:
I've seen this used to test long lines, you return a "blip" wherever there is an impedence mismatch... so sya you have a two mile run of communications wire, you originate a pulse and then watch the echos, you should only get one echo at the termination, if there are other minor blips returning before the end blip you may have cable flaws.... it's pretty much a clear demonstration of termination and cable length effects...
here's a jave applet so you can play with this concept:
http://www.eecircle.com/applets/018/TDR.html
Anyway.... the ONLY way TDR could work is that conductive materials are subject to internal reflections... the practical issue is that audio cables are too short for most testing arrangments...
I think that the TDR phenomena clearly show that energy reflections between impedence shifts (termination, solder joints) are a real phenomenon that few manufacturers confront directly, except perhaps MIT and Transparent...