Rap 'n Tap
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From: Charlie McGinnis charlie@one.net
Date: 9/6/99
Time: 3:48:32 PM
Remote Name: 209.50.99.233
Have you tryed the Radio Shack battery Cat # RSU 10048452, a 45 volt battery at $23.99.
Charlie
From: Steven Coles
Date: 3/20/99
Time: 8:57:58 AM
Remote Name: 207.149.222.142
Through-Ground Communications
Sometime in the late 1950s or early 1960s Popular Electronics published a story on communicating through the Earth's surface. Two of my friends and I tried it. We fed a code practice oscillator into an audio amplifier and connected one speaker lead to a cold water pipe ground. The other speaker lead went to a rod driven into the ground about fifty feet out back (away from the city water lines). Five hundred feet down the block one of my friends used a similar ground arrangement feeding a one-transistor headphone amplifier. With a forty-watt amplifier we could just make out the code practice at 500 feet. Voice was buried in city utility's sixty cps (Hertz) ground currents. Active filters might have extended the range by two or more. Through- ground communication does work. However, it's mostly crummy for anything beyond audio-frequency gee-whiz demonstrations. 1) Electrical signals loose most of their power within a few hundred feet of the starting place. 2) You need to check on FCC rules and regulations before trying anything above 10 kHz. As you go up frequency it gets a little tricky to keep your signal entirely in the ground. 3) You have to sift through a lot of misinformation. The importance of early radio receiver's ground connections and other radio-frequency effects fooled some of the best early radio researchers into thinking substantial amounts of radio energy flowed through the ground. 4) All the easy variations were tried decades ago. However, it is fun if you have a nearby co-conspirator. And, if you drive enough energy into closely- spaced grounds, you'll bring up some good fishing worms.
Seven