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.
Found in a Popular Electronics from the 90s, this game can be seen in other configurations on this site. The...
This control for a heating element was found in an old documentation. The current in the element...
This circuit is from an American documentation of 1975. The FET may be the BF245 and the relay is of...