Big Country,
I am sorry, I have been a Journeyman Electrician for over 20 years 10 of which were Residential, and have Never heard of " Dirty " electric! If what you are stating would be the case, then ALL household electric would be " dirty " because it ALL comes from the same panel! Every circuit in that panel is going to pick up fluctuations in voltage, amperage and resistance every time an appliance starts up, whether it's on the same circuit or not, because it is fed from the same buss!I currently am working in a Polymers factory where they use digital scales all over their laboratory, and have to make VERY precise weight measurements, and have large extrusion machines running 24-7., and we have never had a problem with " dirty electric" effecting any measurements!