I periodically Google PowerLines, just in case. Today, I found a patent that was recently assigned:
United States Patent 7164275
AC power line impedance monitoring method and system
US Patent Issued on January 16, 2007
Two devices that I had a hand in were referenced in the patent. The novel bits seem to relate to a capacitive resonant circuit used to assess the inductive component of the impedance. We are impressed!
Invented by Mike Gaspari, assigned to Rockwell Automation Technologies, Inc. I wonder if they will be coming after me (too late, we stopped selling the ZM-100 a few years back). I’m going to try to contact Mr. Gaspari – because it looks like a neat device and I hope it gets turned into a measurement device.