This circuit of a 1964 Electronic Design uses a photodiode from the time. Modern equivalent can be used. The standby current is 1.2 mA.
We can assemble this circuit from a 1988 publication using more modern transistors. Thus, for Q1...
This circuit generates control signals for stepper motors. We found it in a 90s Popular...
This circuit was found in an old manual of linear integrated circuits of the 80's. Equivalent...