Highly evacuated electron tube for demonstrating the wave nature of electrons through the observation of interference caused by passage of electrons through a polycrystalline graphite lattice (Debye-Scherrer diffraction) and rendered visible on a fluorescent screen. Also intended for determining the wavelength as a function of the anode voltage from the radii of the diffraction rings and the lattice plane spacing of graphite, as well as confirming de Broglie's hypothesis.

The tube uses an electron gun with an indirectly heated cathode to project a narrow converging beam of electrons through a thin layer of graphitised carbon supported on a fine mesh grid over the exit aperture of the gun. The cathode rays are diffracted in passing through the carbon layer and produce a ring pattern on the phosphor coated end of the tube. Study of the ring pattern and it's variation with different anode voltages permits the study and verification of the de Broglie's hypothesis, shows the dual nature of the electron, permits the calculation of the spacing of diffracting planes and suggests the probable arrangement of carbon atoms.

• Operating instructions supplied.

Technical Specifications:

• Maximum filament voltage: ≤7.5V AC/DC
• Maximum anode voltage: 5 kV
• Anode current: 0.15mA at 4kV
• Lattice constant of graphite: d10 = 0.213 nm; d11 = 0.123 nm

Requires the following products to operate:

• B8A49463 - Universal Stand
• B8R02653 - EHT Power Supply - to power the anode
• B8R05926 - Black Safety Lead - for EHT Connection
• B8R05927 - Red Safety Lead - for EHT Connection
• PP00051016 - 2mm Adaptor Lead
• B8G85458 - Bench Power Supply - to power the filament
• Stackable 4mm Plug Leads (black)
• Stackable 4mm Plug Leads (red)