When the voltage in the circuit exceeds the value set in the trimpot, the LED goes off and, if a low current buzzer is used, it rings. The circuit is from American documentation from 1999.
The circuit is from 1968, but we can use a modern one like the 741. The symmetrical power supply...
The circuit presented uses Linear Technology Operationals, having been found in a 1993 manual. The...
Found in American documentation from the 90s, this circuit triggers a buzzer with a Sonalert-type...