Post #1569276

@hennichodernich @tubetime they were very, very common in 60s/70s/80s Nuclear Physics instrumentation, most notably "NIM Crates", where you could check the +/- 6V, 12V, 24V supply voltages. These instrumentation crates were "high density" (for the time) and often lacked built in meters. For example you had 12 HV supplies in 19" width, with 1V/1000V and 1V/1mA monitoring outputs. You just shoved a multimeter probe in the socket and turned the knobs looking at your handheld meter...