This 1980s circuit was found in Motorola documentation. The circuit uses period components that admit of equivalents. Light feedback in a modern version can be done by optical fiber.
April 2017 - The new Maxim Integrated MAX20733 and 20745 switched regulators are available from...
The indicator for this circuit is a mini buzzer with a 1.5 V oscillator. The circuit can also be...
This 80's documentation circuit includes an amplifier of the era. Used integrated circuits are...