Indicated for activation by microcontrollers, this circuit was found in the Radio Electronics magazine of December 1987. The MOSFET can be of any type according to the buzzer.
Using a 4046 PLL this circuit recognizes a 1.6 to 1.8 kHz tone by driving an output LED. The...
This battery charger circuit was found in ancient American documentation. The components are...
This circuit is of great use today, when solar energy is becoming increasingly important. The...