Sorry to have made a hash of this thread below. Can't delete a post that has replies.
I have a pair of what I believe are Siemens E188cc tubes branded Cca. The date codes don't look like Siemens codes I've seen; there are no phis on either tube.
I know that their 6922 tubes have date codes beginning with A and their Cca date codes begin with G.
Can anyone tell me what I have? And what the dates codes mean?
Thank you
