This circuit is suitable for the calibration of old analog oscilloscopes. It was found in documentation from the 1970s and could be useful if someone is recovering an oscilloscope of the time.
The circuit in the figure is from a source with the possibility to adjust the output voltage from...
We found this circuit in a 1965 General Electric manual. The circuit applies to incandescent lamps only and...
We found this circuit in an American publication from 1977. The circuit drives two LEDs according to...