This 1967 Raytheon circuit uses a Raystor, an optical coupler with a lamp and an LDR. The circuit can be adapted to use another type of coupler.
This interesting comparator circuit was found in an old Motorola documentation. The integrated circuit...
This two-transistor constant current source is from a 1968 documentation. Modern equivalent...
An interesting application that finds applications in industry, especially when fluctuations in...