The anode current for such a small screen area is pretty low, I’d guess tens of μA. The flyback also provides a few hundred V to 1 kV for various grids like focus and brightness of the electron gun, which take similar current. Since they all use voltages adjustable in different ranges, a single series of resistors and potentiometers is employed as an adjustable potential divider, consuming usually less than 1 mA (1 W).
With such small sets (or ancient vacuum tube ones), the power draw of the electronics driving the deflection coils is also considerable. I’d guess about 2 W for the CRT heater, 1 W for the HV, 1 W for the sync, amplification and deflection.






Not me, I just theorized. I met people from C3PB (@[email protected]) with their giant Parklight24 display and wondered what it could be used for. Also, @[email protected] had a Geascript display at 39c3, smaller (U/S-Bahn single liner in train) but with proportional font: