We found this circuit in a Popular Electronics from the 90s. Transistors can be modern equivalents. Observe the high supply voltage.
The presented circuit emits signals in the FM band, which can be picked up from a distance of a...
The TDA7053 consists of a class B stereo amplifier, formed by two amplifiers connected in bridge...
This circuit activates a piezoelectric buzzer with an oscillator at the end of the programmed...