Published in Radio Craft in July 1946, shortly after the war, therefore, it is a sensitive tube metal detector. The circuit is of the type with two coils which are connected to the main circuit as indicated in the diagram.

Published in Radio Craft in July 1946, shortly after the war, therefore, it is a sensitive tube metal detector. The circuit is of the type with two coils which are connected to the main circuit as indicated in the diagram.