The selected circuit is from the Texas Instruments optoelectronics manual. With it you can receive optical signals in CW. Transistors support equivalents.
Found in Motorola documentation from the 90s, this circuit makes use of a triac from that time. The...
This transistorized signal injector was one of the first that we found using the well-known...
This 200-mW amplifier uses one of the first commercial power transistors. The circuit is from a...