The CV56 is an S-Band magnetron operating at a wavelength of 9 cm. It was used in the Type 271Q naval radar and was pulse modulated. The pulse peak power was of the order of 90 kW and the conversion efficiency was close to 40%.
This cavity magnetron screws into waveguide via the 15 mm thread seen at the left side of the picture. The output is coupled to the waveguide by the probe. This exhibit has the glass seal broken. Internally the copper anode block has the cavities strapped together and the CV56 was the first production magnetron to use this technique.
The probe, waveguide thread and coolings fins.
The filament and cathode connections are insulated by the ceramic beads. To avoid the waveguide being at a high voltage the anode would be grounded and the cathode would pulse many kV negative.