Siemens “Pantix” Tube

Ref. K3

In spite of its modern shape, this 1950’s tube bears the same name “Pantix” as the earliest Siemens rotating anode tube introduced in 1933 (see picture below).

It has a small and a large focal spots, with corresponding filaments of unequal lengths, and a single focal track on the anode disk. The small focal spot measures 1.2 square mms and the large focal spot 2 square mms. The power output of the tube is 20 kW for the small focus, and 40 kW for the large.

This tube is non functional because at one time the anode stopped rotating due to a problem in the rotating mechanism, resulting in small deep melting crater on the focal track. The track itself has otherwise a rough surface due the long use of the tube.