Metropolitan-Vickers demountable tetrode valve, type 43 E3
1939
Demountable tetrode valve, type 43 E3, with water-cooled anode; cathode and grid; flange; and gasket, by Metropolitan-Vickers Electrical Co. Ltd., Trafford Park, Trafford, Manchester, Cheshire, England, 1939. The demountable tetrode valve was part of a Chain Home Transmitter.