The university mainframe had some PDP-11 frontend communication controllers (the less said about IBM's 3705, the better). One day, the DEC repairman came in to fix one of the PDP-11s, hooked up his oscilloscope, and the mainframe went dark. It turned out that there was a floating ground and when the oscilloscope was used, it connected the floating ground to the real ground and blew the fuses (and some other things - there was probably smoke from the oscilloscope and/or the PDP-11).
Matt Panaro (npub146z…8pmv)
Peter Ludemann
npub107…yqqc4
2026-03-20 18:06:36 UTC
in reply to nevent1q…n3gs
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2026-03-20 18:06:36 UTCEvent JSON
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