At 09:27 AM 5/29/96 -0400, SINCLAIR DOUGLAS N wrote:

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Water pipes are often form the earth line. If only 60hz (US) can get through the power cables then only 60 hz can get into the water pipes (I'll ignore re-radiating, because water pipes are the least of your problems there).

The high-frequency harmonics from your computers are probably above the cutoff frequency of the water-pipes when considered as circular waveguides. The water filling will act as a dielectric, bringing F0 down. So, it is conceivable that extremely high frequency radiation (>3 Ghz) could propagate well in a water pipe.

No, you misunderstood. The RF wouldn't be transmitted on the inside of the pipes (how could it get inside, anyway?) but on the outside. Since most information-containing appliances are well-grounded, there is at least a strong possibility that a ground connection would carry enough interesting RF to be useful to tap. Jim Bell jimbell@pacifier.com