Marconi Radio Valve Type V24, by Marconi Company, English, Early 20th Century

Marconi Radio Valve Type V24, in thin glass envelope with caps at either ends, with grid and anode connections as envelope side pips, and single strand tungsten filament running entire length with a spring for tensioning. Construction was co-axial with helical wire grid surrounding filament and fitting within cylindrical anode. In this valve, 'U' shaped glass support holds two stout wire rods that attach to anode and grid respectively; thus electrodes are only supported at one end. Previously catalogued with assorted other valves.