This circuit was published in the July 1993 issue of Electronics Now magazine. It uses a sensor from the time and triggers a buzzer with a Sonalert-type oscillator.
This circuit uses a 7-segment display to indicate the logic level of a test circuit. The power...
With the circuit shown, we have an excellent level for the signal obtained from an electret...
The integrated circuit used in this project is an old voltage comparator, since the configuration was...