I'm an experienced electronic engineer with a particular interest in scientific instruments,

from phased-array medical ultrasound scanners (though I've not worked on one since 1979 and they've come on a bit since then),

through electron-microscopes and their cousins, the electron-beamer tester and the electron-beam microfabricator,

to basic stuff like millidegree thermostats, photosensors and magnetic field sensors.

Even cranky components like photodiodes, photomultipliers and interchangeable thermistors rarely surprise me these days.