The Marconi V24 valve was a development of the 'R' type aimed at improving the high frequency performance. The V24 was designed around 1919 and was used as an RF amplifier with a filament current of 0.7 Amps. The anode voltage would have been in the range 24 to 50 Volts. The V24 itself being an indication of the use of standard 24 Volt supplies of the type used on board ship for lighting.
The grid and anode connections are to side pips on the envelope and the single strand tungsten filament runs from cap to cap, with a spring for tensioning. The construction is co-axial with the helical wire grid surrounding the filament and fitting within the cylindrical anode. In this valve the 'U' shaped glass support holds two stout wire rods that attach to the anode and grid respectively. These electrodes are thus only supported at one end.
This exhibit is damaged and has lost the side caps revealing the wire passing through the glass.
The helical grid is fixed to the single side support by a thin wire wound round each loop.
The anode connection minus the side cap. The cement is still partly present. The anode cylinder can be seen to have a folded seam.
The grid side connection showing the wire emerging from the glass.
The filament tension spring with the fold at the end to hold the tungsten filament.
The thin glass tube envelope is 18 mm in diameter and, tip to tip is 73 mm tall.
References: Data-sheet & 1003. Type V24 was first introduced in 1919. See also1919 adverts.
