I suspect some of the newer, "pure digital" stuff barely needs any actual work, and most "calibrations" are really just a verification/expensive sticker. Back

I suspect some of the newer, "pure digital" stuff barely needs any actual work, and most "calibrations" are really just a verification/expensive sticker. Back then (mid-1980s), even the digital stuff had a lot of analog circuitry, and some of these huge high-bandwidth spectrum analyzers (for example) would have hundreds of micro-pots. Calibrations could take days.