This circuit is from a documentation on the MC1539 from Motorola and may, however, be implemented with equivalent operations. The transistor also supports equivalent.
This circuit drives a buzzer or electric buzzer but can be used to trigger a relay or other load....
Found in Popular Electronics from the 90s, this circuit can be used for high voltage applications and...
August 2016 - The new Schottky diodes from Vishay's ESMP series for surface mounting can now be...