Electron Beam Tube, Double, Type D

This low-pressure, neon-filled electron beam tube makes electron paths visible. It has two electron guns — one axial and one tangential — set perpendicular to each other, and the two beams appear as luminous traces as the neon atoms are excited. In atomic and electron-beam physics the tangential gun, combined with a perpendicular homogeneous magnetic field, can be used to determine the electron's specific charge e/m, while the axial gun, with a partly coaxial magnetic field, demonstrates spiral paths. It is ideal for class demonstrations. Dimensions (ø x h): 130 mm x 260 mm; gas: neon. Recommended power supply: 500 V DC (365580).