Maybe a long shot but I'm giving it a try.
Is there possibly someone who has a schematic on the Nevaton MC/MK-51 microphone?
It is unusual, but I have now received two of these microphones for repair from two different customers.
I have been in contact with Nevaton in Russia but they do not respond, and Nevaton Europe does not want to help with schematic or technical advice, they want the mics to be sent to Russia for repair, but none of the customers are eager to do this.
I normally do not have difficulty for drawing/tracing the electronics in a microphone even if it is complex, but these are full of Russian components with tricky marking/text.
Of course, it is possible to sneak out component type and values, but it saves a lot of time and there is less risk of misunderstanding with a schematic.
--Bo