This circuit is from a 1980s Signetics documentation. The circuit separates the modulation signal from a carrier. The used components are not common today.
This sensitive motion sensor with inductive sensor was found in a 90s Elektor. The circuit uses only...
This simple balance indicator for sound equipment was found in a 1982 documentation. The M1...
This circuit was found in a 1992 documentation. It uses a photo diode as a receiver and an...