Franck-Hertz Tube with Ne Filling
For demonstrating that free electrons colliding with neon atoms emit energy in quantized packets and for determining the excitation energy of the 3P0 or 3S1 states at about 19 eV. When excited, these states emit visible light due to the energy drop from intermediate levels to a ground state at an excitation energy of about 16.7 eV. The light so emitted is in the red-yellow region of the spectrum. Bands of light develop between the control grid and the accelerating grid. The plane-parallel geometry of the grids means that these bands can be viewed through a window. Unlike the mercury-filled Franck-Hertz tube, the neon-filled version can be operated at room temperature.
Tetrode with indirectly heated cathode, mesh control grid, mesh accelerating grid and collector (counter) electrode. Mounted on a base with color-coded connection sockets.

Filament voltage: 4 to 8 V AC / DC
Control potential: 9 V
Accelerating voltage: max. 80 V
Countervoltage: 1,2 to 10 V DC
Tube: 130 mm x 26 mm Ø approx.
Base with connector sockets: 190x115x115 mm
Weight: 450 g approx.

Additionally required:
U8482130 Power Supply Unit for Franck-Hertz Experiment
U11175 Analogue Oscilloscope