How to read Russian tubes

or more on the confusions with the tube marking and numbering systems

 

By the questions I've received lately more people are using NOS Soviet/Russian made tubes for reason of availability, good sound quality and prices. For most of the people not familiar with Cyrillic* characters that creates some difficulties understanding properly tube type and which is the European or USA made substitutes for any particular type need to be replaced. Some of the tube dealers may have some information to share, which is may be incomplete and sometimes even wrong. Information on that subject is not widely available and by comparing tube data charts and pin outs sometimes we are not able to tell if the substitute made in Russia is same as the type we need to replace. Sometimes the confusion becomes worse, because for some exports the Russian manufacturers have replaced some Cyrillic characters on the marking with the Latin one, because of the market, OEM or dealer requirements and that is another mystery to solve. And all that additional data is NOT IN THE BOOKS. The web gives some answers to that problem - some number of Russian sites have excellent data, but to read it you have to know how to read it - same if you need soldering iron to repair the soldering iron. And still all the available web info is incomplete and even Russian engineers can't tell the difference of some particular number of given tube with same parameters. To create more confusion some of the tubes have also marks as fifth, sixth or seventh character, with greatly unknown meanings. In the following table you will find how to read receiving type tubes marked in Cyrillic.

 

 First character - digit

 Second character-letter

 Third character - digit

 Fourth character-letter

 Fifth or higher character-letter

 shows rounded filament voltage value

 shows general type tube

  shows type tube

  shows construction of the tube

 shows some extras for the construction of the tube

 1,2,3,4,5,6,7, 9,12....e.t.c
 

  1,2,3,4,5,6,7, 9,12....e.t.c
   

* Cyrillic - an alphabet, developed for Bulgarian church from St. Cyril, first used for the writing of Old Church Slavonic, later adopted with minor modifications for the writing of Bulgarian, Russian, Serbian e.t.c.; first derived from Greek uncial.

for Cyrillic-Latin table look here

Few common direct replacements Russian - USA made tubes

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