This UPS circuit was published in the March 1985 issue of Radio Electronics magazine. The components used are still common, although some may be difficult to obtain.
This filter is suggested by the Texas Instruments Linear Circuits Applications, 1986 edition. The...
This CMOS circuit was obtained in a 1980s documentation. The circuit has a 10-second time delay...
This circuit consists of a switched mixer with digital touch control. The circuit was found in old...