ID:
269
Maker's Name:
20th Century Electronics
Where made:
England
Dimensions:
19 × 2.9 × 2.9 cm
Glass tube filled with vapour at low pressure. A cathode along the tube axis and a cylindrical copper gauze anode have a voltage of 1100 Volts between them. High speed electrons passing through the tube ionise the vapour and initiate a momentary discharge.