This circuit was found in a 90's EDN. The circuit provides two 15 V outputs and one 5 V output from the 12V voltage of a car battery. The components are from that time.
The transistor can be the BD135 and this circuit, found in a 1978 publication, can be powered by...
This interesting circuit measures the distortion of the sinusoidal voltage of the power grid. We...
This sophisticated circuit is from a 1975 documentation. The components are from the time and the...