This circuit was found in Motorola documentation from the 1980s. The components are of the time, not currently common as operational and opto receiver.
This circuit was obtained from an English publication from the 70's. The circuit is still current for...
This circuit makes use of an unusual Analog Devices component today. The circuit is from a 90's...
This circuit was found in a 1974 documentation. The bipolar transistor can be the BC548 and at the...