Another good source for an ultrasonic (US) kit and a construction article is www.midnightscience.com, website of The Xtal Set Society. I built a receiver (about $150) on their instructions. It has been so successful our local very responsive power coop bought a $4500 commercial version.
The power coop didn't make this investment out of gratitude for my discovery of numerous noise sources, although I did that with my combo IC706, VHF whip on the car, and US detector. They did it because they had a cost study done that concluded about 7% of their energy was going to ground via noisy leaks. Old infrastructure seems to be the primary culprit around here. The study prompted the employment of an engineer, an expensive receiver specifically intended to find leaks, and (after seeing mine in action) the US detector. Their commercial US detector is 30 times more expensive than my plumbers delight model, and perhaps twice more effective. Their receiver is a real asset. The noise engineer and I hook it to my antennas, note the pulse characteristics of the power leak, then are able to practically drive right to it. Some of the time anyway and given a pretty strong QRN signal. The bad news is no matter how successful I am new sources keep on coming on. Stuff breaks, the temperature varies, the wind blows, lightning strikes, the line crews over and under tighten hardware or install wrong, poles decay away and catch fire, birds fry - a never ending task. If anyone's interested in photos please email off the reflector k6xt at arrl dot net. -- 73 Art K6XT~~ near Allison Colorado Success is going from failure to failure without a loss of enthusiasm. _______________________________________________ UR RST IS ... ... ..9 QSB QSB - hw? BK