United States. Air Force. Cambridge Research Laboratories
overall: 1/2 in x 4 1/2 in x 6 in
Pentode and Gate module consists of a circuit board in a three sided orange frame with three miniature vacuum tubes on the component side. Handwritten text in upper left corner reads "OK". "TRANSFER UNIT" is written on the frame. "OK" and unreadable handwritten text is written on the trace side in red grease pencil.