The CV2193 is the service designation for the Cossor 89D oscilloscope cathode-ray tube. This tube dates from 1951 and in addition to having a flat face-plate it has a splitter plate that divides the beam into two. Each Y plate then acts on one half of the beam only and thus a true dual beam 'scope is produced albeit with single ended Y deflection. The X plates are common to both channels.
This particular tube was found on the last day of trading of the last electronics emporium in Lisle Street in central London. The date was the mid to late 1970's. I believe that first thing in the morning they were asking £1.00 but at 18:00 I bought it for 50p.
The phosphor is medium persistence green and the tube gives a useable trace with 1,000 Volts across the tube.
The identification on the tube and gun assembly within. The Bakelite base sleeve has the connections built-in. These consist of a flat plate bent to enclose a triangular space. The space accepts standard 4mm plugs.
A closer view of the gun, grid cylinder and first anodes.
The base has the contact identification printed onto it.
The virtually flat faceplate has to withstand very considerable inward pressure and shows how glass technology had developed by the early 1950s. The diameter across the face is 105mm.
Looking down across the flat face-plate. Note the colloidal graphite inside the bell that is the third anode.
The end window envelope is 70 mm in diameter, and excluding the base pins is 405 mm tall.