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.
The frequency of this circuit is determined by the 100 uF capacitors. These components can be...
This crystal-controlled 1000 kHz oscillator was found in 1980s American documentation. The...
This circuit was obtained from an American documentation from 1976. The circuit has a dynamic...