Many old buildings/houses in Europe are so old that they were not built with a grounding system. I happen to live in one were this is the case. The problem is that if I want to use an oscilloscope, it picks up mains disturbances up to 1 Vpp due to the absence of grounding.
What options do I have?
My building has a grounding only on some outlets and while I have the option to run a power cable across the building where there is earthing, I'm pretty sure this would lead to further 50 Hz radiated disturbances on the cable, I will test this as it currently is the most viable option.
I don't need to work on hazardous voltages (at worst I'll be working on 24 V DC).
Please do not remind me of why I need grounding (other than for having a decently working oscilloscope). I am aware of that, and I try to be as cautious and safe as possible when dealing with any kind of electrical system.