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.
This two-transistor circuit was found in the August 1972 issue of Radio Electronics magazine. The...
The purpose of this circuit is to automate the activation of an aquarium air pump (aerator). The...
This circuit is from the 1983 Intersil Databook. The circuit has an A / D converter for display of 4 and...