This flashing allegory with 555 integrated circuits was found in the Radio Electronics Experimenter magazine from 1989. It is a simple circuit to assemble.
This variable oscillator with power step for alarms was found in an American documentation from...
This circuit was found in a 90s Radio Electronics. It produces an ultrasonic signal in a special...
This circuit is only used for resistive loads such as incandescent lamps. The bridge diodes can be...