The 5C22 is a hydrogen thyratron with a short de-ionising time for high pulse rates. The envelope also carries the UK service Type designation of CV2520. The base is the 'Super Jumbo' bayonet B4D.
These glass thyratrons are used as pulse generators and it was designed to work with a pulse transformer to generate higher voltages.
The top of the glass is reentrant and thus holds the anode closer to the top of the shield. The anode is a disc within the perforated top of the shield.
The pinch components.
The wide glass tube envelope is 63 mm in diameter and, excluding the special base pins, is 195 mm tall.
Reference: Data-sheet. Type 5C22 was first introduced in 1955. See also1955 adverts.