Hello everyone! Immediately apologize for mistakes and illogicality in the text, I am from Russia, and write through a translator. Apologize.

Now about the main thing. I can't find the circuit, the oscilloscope "HP 54520a". Climbed a lot of sites, of. site and still can not find. If anyone has digitally, I will be very happy!!!

Also, I wanted to ask. Should such an oscilloscope be considered for purchase now? There is opportunity buy for 300$ such, I have now Soviet S1-49, S1-83, S1-101 and very long dreamed about overseas, and importantly with CRT monitor. For some reason they have a soul, warm, tube oscilloscope:) Just like an amplifier. Just now for about the same money there is a DSO5102P from China. On the Russian forum, opinion is divided on this matter. Maybe you can say something.
THANK for any help!

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I wanted to ask you something else. At self-diagnostics there is an error "disk". Is it scary? What can it be connected with? Just the seller says that the battery inside the oscilloscope died, and if it stands it does not turn on. If its "push" the insurance is. What's the battery? And what can replace it? Is this a serious problem?