The signal from this transmitter is injected into a cable that you want to follow along a pipeline. Monitoring is done using an ordinary AM receiver out of season.
This circuit was obtained in a 1982 English magazine. This circuit can be used both as a simple...
This sensor triggers an oscillator emitting sound when a magnet is approached by a reed switch....
Suggested by Burr Brown in 1969 documentation, this circuit makes use of an integrated component...