LM566/3

LM566 was the Telefunken experimental code for LMS12. It was one of the few multi-cavity magnetrons designed in Germany during the war. Intended to operate at 3 cm, its anode block had 18 cavities. As opposed to LMS10, copied from a British magnetron, this looks to be an original German design. The system of resonators is placed transversely with respect to the tube axis. Anode and cathode were assembled on a ceramic disc and then inserted into the upper sleeve and brazed to it. Anode was conduction-cooled through the sleeve to a suitable radiating mount. Some doubts arise on the efficiency of a 18-cavity structure, but likely German technicians relied on a control loop on the current flowing in the electromagnet to stabilize its operation.

• 16 kV at 10 to 15 A input pulses. 1900 to 2100 gauss magnetic field.
• 3.05 to 3.35 cm wavelength
• 10 kW output power typical

Used in a few tens of Berlin D airborne X-band radar sets and in some other sets still experimental when the war ended.