[Pinörkel]

Thanks to your hints, I managed to remove the Delay/Time Mult knob. Now, there is something stuck near the labeled plastic cylinder of the Time/Div knob that is preventing me from taking the front panel off. Seems like I have to figure this out another time.

Today, I thoroughly cleaned the vertical position double potis including the trimmers. Most of their hick ups are gone now, however, the trimmers are still very fiddly.

Upon pressing the shaft collar into the modified Time/Div knob I got from Alistair D, I noticed a small crack on it that started to widen. This was easily fixed with some epoxy and two cable ties pressing the knob together.

For calibration of the scope I acquired two Cinch 81 731 AA 16 edge connectors (see images). These are just like the build in Cinch 81 774 AN 16 module connectors, except they have gold plated contacts on both sides and do not have the reverse polarity protection gap. I am planning to use these and some custom cut PCBs to build extension cables for both modules for live measurements and calibration.

This week I was allowed to play with an equally old Hameg 412-5 scope. I was amazed how responsive and stable it was compared to my D75. No trace drifting over time, no 5x trace offset, a consistently and stable working trigger control, virtually no warmup time and absolutely no trace hick ups on using any switches. At the moment I can't judge how a D75 should behave in perfect condition. Do you have any experiences on that? This would make it much easier for me to identify aspects that should be fixed by, for example, locating and replacing bad and heat sensitive components.