Solved a very difficult tech problem at a customer clean room site in San Jose at midnight last night. So I get to fly home tonight.
For the curious, my equipment had problems calibrating in the highest sensitivity range, around 10mv full scale. Challenge was doing it in 100us, so no time for traditional averaging over a few thousand measurements. Worked perfectly in my lab, of course. Root cause was the customer had a low voltage lamp a foot away from my circuit, and the wall plug power supply for this cheap - ass lamp generated far more noise than the CE regulations allowed. Chinese crap.