Found in American documentation from 1969, this circuit switches signals with a FET of the time. The circuit can be implemented with modern equivalent transistors.
This is yet another simple LED driving game circuit that appears in several other versions on this site....
We found this circuit in a manual of optoelectronics from Texas Instruments. In it photodiodes or...
This interesting circuit is from a 1988 documentation. It is a matrix of diodes that converts...