The 3B24WA is a high voltage half wave rectifier with a moisture stable base.See also 3B24W & 3B24.
The datasheet quotes anode voltage up to 20 kV but this probably a peak value.
The picture above shows the makers logo on the base and the graphite anode that can operate up to 820°C.
The picture above shows the bonded thoria tungsten core helical filament. The anode is substantial in this exhibit and much less so for the 3B24W
The wide glass tube envelope is 38 mm in diameter, and excluding the UX4 base pins, is 103 mm tall.
Absolute Maximum Operating Conditions¶
Updated January 26, 2013. shape:wide.glass.tube construction:pinch type:rectifier.hw age:1940.1950 base:ux4 heater:5.0v pins:4 pin:1.f(tap) pin:2.f pin:3.- pin:4.f pin:tc.a