Dear Sir
Is the valve ECH22 equivalent to ECH21? If not what is the difference? What is the base diagram for the valve ECH22. What were the radio sets in which this valve was used?

Regards
P.Rajan

The ECH22 is not identical to ECH21 but to CV302.
For specs: http://www.tubecollector.org/cv302.htm

This valve was used as mixer/oscillator in broadcast receivers and commercial communcation receivers.

Jan.

Hello,

This valve was also used in non-commercial professional admiralty, navy, airforce shortwave and very longwave Murphy B40 and B41 receivers.

The ECH21 can be used in stead of the original ECH22 (= equal to CV302) by using an socket adapter or by changing the sockets pin conections on the receivers chassis. Using a valve socket adapter is the best solution. The ECH21 and ECH22 function in exact the same way. With the techspecs disgarded they only differ in the pin connections.

best regards,

Sander

My Dear Mr. Jan

Thank you very much for your reply

Regards

P.Rajan