The configuration shown was found in an old Poptronics but can be easily assembled using a common calculator photocell. The relay is according to the supply voltage.
This circuit with traditional discrete components was found in a 1990 documentation. The circuit can...
This differential pulse shaping amplifier was found in documentation from the 1980s. Switching...
This mid-frequency amplifier circuit was found in an American publication from the 1950's. The...