This wonderful little oscilloscope tube caught my eye at an amateur radio 'junk sale' in the 1980s. The type designation has been rubbed off but it came with a sheet of paper wrapped round it giving its operating conditions. In use the trace is a standard green.
The a3 voltage is 800 and the a2 voltage is 192 Volts. The grid voltage is -12 Volts for beam cut-off. With these conditions 60 Volts RMS gives 40 mm Y deflection. The same 60 Volt sine wave gives 35 mm X deflection.
The base with leads soldered on the Ct8 base.
The screen is 65 mm diameter within the rubber screen protector.
The end window envelope is 32 mm in diameter, and excluding the Ct8 base pins is 162 mm tall.