This circuit activates a buzzer when the voltage applied to the input falls below a preset value in R1. The circuit is from an 80's American documentation.
This circuit can measure frequencies up to just over 1 MHz and uses CMOS technology. The circuit is...
This circuit, found in 2002 documentation, generates a strong audio tone when the light in the...
The integrated circuit used in this 80's application is not common today. However, modern...