ECH22 (Techniek Radio/TV)

door Pandu Rajan , 10.10.2008, 07:17 (5700 dagen geleden)

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