We found this circuit in a 1991 Hobbyst Electronics. The circuit makes use of an unusual transducer today. It is a piezoelectric buzzer that can eventually be replaced by an equivalent configuration.
Found in a November 1977 Radio Electronics magazine, this digital circuit was described in an...
This circuit is from a manual of linear integrated circuits of the 80s. The operational is of the...
The tone generated by this bell changes when we press and release the switch. The circuit is from...