CAT 9 MOV, 1937

CAT9 18KW 50 Mghz High Power Triode for Transmitting, air and water cooled.
750mm 2Ft 6inches long. CAT= Cooled Anode Triode
A water cooled transmitter triode. The filament connections are at the top, the grid at the side (RHS in the picture), and the anode is the copper lower half of the valve. The ring between the copper and glass is to allow a blast of air to cool the seal. The anode corona shield incorporates a connector to allow air blasting off the seal for cooling.
Used by the BBC sometimes in pairs.

Your comments:

• 2 cat 9's were used in the SWB 10 transmitters at Graetworth and Dagnall
  .......... Turner, Cranleigh, 7th of January 2012
  
  

A0584