This small transmitter appeared in the March 1989 issue of Radio Electronics magazine. The two-transistor circuit used an electret microphone and had a range of a few dozen meters.
We can control the frequency of an oscillator from digital circuits or from the output of a...
We recommend adding a 470-ohm resistor in series with the potentiometer in this dimmer circuit...
We found this circuit for old tape recorders in the December 1972 Radio Electronics magazine. The...