The E639/10 magnetron is a development of the original magnetrons. It was found that by increasing the number of anodes the operating frequency could be increased. A major secret of the second world war was the development of the cavity magnetron for radar. In this valve can be seen the early experiments in anode segmentation.
All anodes are brought out to top pins and the filament is taken to the base. Like all magnetrons the valve has the electrical structure of a diode.
These early magnetrons were not particularly stable and they did not find widespread use, unlike the cavity magnetron.
The wide glass tube envelope is 39 mm in diameter and, excluding the base pins, is 110 mm tall.
Updated April 23, 2013.