This circuit was suggested by General Electric in a 1969 documentation. The transistors are of the time and the power supply is not given. Note the high supply voltage.
This circuit provides a constant current of 1 mA, stabilized by an LED, which can be equivalent to that...
This receiver for the mid-wave band was found in a documentation from the 60's. The transistors are made...
This circuit converts a positive CMOS supply voltage to a negative one. We found it in a 90s...