Found in the June 1987 issue of Radio Electronics magazine, this circuit uses well-known CMOS components. The circuit has a CMOS amplifier stage that drives a small speaker.
This circuit from a 1966 General Electric manual makes use of an SCS. The time is given by the...
The circuit shown in figure 8 is an application suggestion for ISL8107, a new integrated circuit from...
This four-digit circuit was found in a 1990 documentation. The sensor can be a contact or reed...