Sensibly equivalent¶ to:
The 3BP1 oscilloscope tube has a medium persistence green phosphor and a three inch diameter screen. Actual maximum diameter is 77 mm.
The 3BP1 design dates to the mid 1940s but was a popular choice for home construction oscilloscopes up to the 1970s.The main image shows the electron gun, the etched identification and the internal colloidal graphite coating that acted as the final anode.
The screen end of the tube.
The wide glass tube envelope is 52 mm in diameter, and excluding the base pins is 238 mm tall.
Reference: Datasheet. Type 3BP1 was first introduced in 1944.
Absolute Maximum Operating Conditions¶
Updated October 22, 2015. shape:end.window construction:pinch type:cathode-ray.tube age:1940.1950 base: heater:6.3v pins:12 pin:1.h pin:2.k pin:3.g1 pin:4.ic pin:5.a1 pin:6.- pin:7.y1 pin:8.y2 pin:9.g2 pin:10.x1 pin:11.x2 pin:12.- pin:14.h