bell-howel: Blurry copy of schematic for BH Model 34 Oscilloscope 138644

There are two schematics on the page for the Bell & Howell (DeVry Institute) Oscilloscope model 34. It would appear there are likely two variations of this 'scope as the one I have has a different tube 6AF11 than any of the tubes shown in the first schematic. The second yellowed schematic is just a thumbnail and does not show clearly at all when downloaded.

I'm hoping that Karlheinz Gutzlaff has a better copy he can upload as the second schematic appears to match my machine.

What I am surprised about is there is NO fuse in this unit! What were they thinking! I am using a line fuse of 3/4A slo-blow for 120VAC operation.

This is similar to the Heathkit Laboratory 5" Oscilloscope model IO-12. I don't have any other Heathkit 'scope schematics and I saw on an old posting somewhere else that the person thought Heathkit was the source for DeVry Institute stuff. And I understand that Heathkit stuff was designed by some other company whose name I have forgotten - but I could be wrong.

Thanks!

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Tahnk you, John, I have deleted the blurry one, but you find still the one which is perfect here.

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