This amplifier with the EL84 tube is a European commercial type from Corpim mounted on a printed circuit board. The diagram appeared in a September 1958 Radio Electronics magazine.
We found this circuit in a 1980s documentation. The circuit uses general purpose transistors,...
This simple circuit for experimental LED sequencing is based on a multivibrator with transistors....
This circuit is from an American documentation from 1975. The circuit uses components of the time...