This indicator or logic probe was found in the April 1979 Radio Electronics magazine. The integrated circuit is the 555 and the FET can be any general-purpose type.
This stage was found in a 1964 Electronic Design. The transistors are of the time and the shape of...
This unregulated symmetrical power supply was found in the August 1982 issue of Radio Electronics...
This circuit was found in an application manual from the 1980s. The operational amplifier used is not...