Found ina 1970 American documentation this fast-reading circuit uses a photodiode. Transistors support modern equivalents. The circuit can be used as a shield.
The integrated circuit used in this application is a double 741 from SGS. The supply must be...
This well-known configuration of the guitar effects pedal was obtained in an English magazine from...
This detector uses an unusual sensor today. The circuit is from an 80s documentation. Its...