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 sixty Japanese commercial radio used 6 transistors in a superheterodyne configuration for...
This circuit consists of a small inverter that can generate a few hundred volts of DC voltage...
This circuit activates a piezoelectric buzzer with an oscillator at the end of the programmed...