Aside from the well known СДЕЛАНО B CCCP (made in USSR) and OTKxx markings there are often more such blue stampings:
- a one/two digit number in a diamond - I've seen numbers between 0 ... 23
- same but in a pentagon
- and just recently a batch of newly aquired 6С19П-В show a "Э" (ee) like a mirror image Euro sign in a circle.
What do the numbers inside the diamond or pentagon mean ? does somebody have a list ?
I vaguely remember a posting by @Wavebourn who mentioned these indicating the intended service in military equipment but I cannot find it anymore.
What's the difference between the diamond and the pentagon ?
And what does the Э in a circle stand for ? I hope it does not mean "scrap" or "reject".
Here are some pictures.
- a one/two digit number in a diamond - I've seen numbers between 0 ... 23
- same but in a pentagon
- and just recently a batch of newly aquired 6С19П-В show a "Э" (ee) like a mirror image Euro sign in a circle.
What do the numbers inside the diamond or pentagon mean ? does somebody have a list ?
I vaguely remember a posting by @Wavebourn who mentioned these indicating the intended service in military equipment but I cannot find it anymore.
What's the difference between the diamond and the pentagon ?
And what does the Э in a circle stand for ? I hope it does not mean "scrap" or "reject".
Here are some pictures.
Attachments
I have seen the Pentagon/Diamond/Triangle with number marking one couple of tubes I have...not too sure but I too vaguely remember something Wavebourn posted, some time ago.
I havent seen that character on any of my collection though.
I take it back...here is another example.
I think the number 7 in polygon is for aerospace/mitiary use, but I could be wrong.
This valve is 1J24B rod pentode, and also has this character "Ze" or perhaps the ezh. I know very little indeed about Cyrillic
I havent seen that character on any of my collection though.
I take it back...here is another example.
I think the number 7 in polygon is for aerospace/mitiary use, but I could be wrong.
This valve is 1J24B rod pentode, and also has this character "Ze" or perhaps the ezh. I know very little indeed about Cyrillic
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Diamond mark means military acceptance. The symbols inside the diamond are just a personal code of military inspector. They're not necessary just one or two digits - you can also find letters, and I've seen markings up to four symbols long. You could come across the statement that those numbers somehow represent quality grades, but that's BS (military quality grades did exist, but the markings were put on the bulk package only, not on the individual devices).
Rectangles, pentagons and triangles with (and sometimes even without) symbols inside are just civilian quality control marks with inspector codes.
"Э" means "for Export". Those are usually slightly better (at least slightly better quality controlled).
Rectangles, pentagons and triangles with (and sometimes even without) symbols inside are just civilian quality control marks with inspector codes.
"Э" means "for Export". Those are usually slightly better (at least slightly better quality controlled).