Its the same osciloscope just the tube in it is different but i cant find any more information i searched everywhereYour photo shows that it is an H313 not an n313. Google has many links about it, some are in its foreign language.
Thank you very much but the only thing i cant find is the maximum frequency itcan mesureYou didn't look under the rug:
https://www.eserviceinfo.com/index.php?what=search2&searchstring=N313+H313
and...
https://lmgtfy.app/?q=russian+H313+oscilloscope+osciloskop
feed it a square wave and get the rise time 10% to 90%. https://www.allaboutcircuits.com/te...p-between-rise-time-bandwidth-digital-signal/
BW=0.35/Tr
Thank you very muchThe sm is in Russian and not russian characters, so google translate won't help. My guess is 20 MHz.
Bandwidth is usually the -3db point or when the signal is down 0.707 or 70.7% Usable bandwidth is generally higher, but the amplitude would be off.
I asked the previous owner he sad that it's around 20Mhz but thankyou for the replyThe reason why I said 20, is that I looked at the service manual and even though I don't know Russian, I was looking for numbers and therefore 20 stood out. Not sure what page it was.
Something like this: https://convertio.co/ocr/russian/ might work first.
then translate.google.com