The VT-222 is the designation for Type 884 thyratrons supplied to the USA government. The Type 884 is an argon filled thyratron used for sawtooth generation in line timebases in early CRT systems.
The box anode held in place at the top by the mica disc that touches the glass.
The oval central section of the anode. The control electrode is covered by the screens top and bottom, the minimal holes in the mica discs and the anode that touches the mica sheets.
The classic envelope is 38 mm in diameter, and excluding the IO base pins, is 89 mm tall.
