The circuit presented was suggested by Texas Instruments in an opto-electronics manual. The transistor can be the BC548 and the supply voltage depends on the application.
This isolated shield is from an old documentation, making use of an operational one of the time. It...
This circuit can be used with receivers to attenuate signals that may cause interference. The...
In this circuit of an American documentation of the 90s, when the light is cut, we have the...