This circuit was found in a 1945 documentation. It consists of a 3-tube multi-band commercial signal generator. One of the tubes is double and the other consists of a full wave rectifier. The frequencies depend on the coils.

This circuit was found in a 1945 documentation. It consists of a 3-tube multi-band commercial signal generator. One of the tubes is double and the other consists of a full wave rectifier. The frequencies depend on the coils.