The tone generated by this bell changes when we press and release the switch. The circuit is from a 1985 Radio Electronics. Some changes can be made to improve its performance.
This circuit activates a buzzer when the voltage applied to the input falls below a preset value in...
This simple window comparator based on the well-known LM339 was found in the June 1998 issue of...
This circuit, which can act as a shield, was found in a 1990 PE Hobbyst Handbook. The circuit...