Page:The Bell System Technical Journal, Volume 1, 1922.pdf/13

Rh tension insulation could be more easily provided and a larger tube was, therefore, designed capable of delivering 10 to an antenna at a plate voltage of 10,000 volts.

The final form adopted for this tube is shown in Figs. 8 and 9.



The anode A is drawn from a piece of sheet copper and is 9″ long and 2″ in diameter. The copper flare B is turned down to a sharp edge and a glass bulb C sealed thereto. The grid and plate assembly is shown at D. The structure is supported by four molybdenum rods, which are threaded and secured by means of nuts to the lavite pieces E and F. The filament is made of 19.5″ of .025 pure tungsten wire purchased from the General Electric Company and is formed and secured to two of the molybdenum rods at G and H. The