Some of those old IBM mainframes are still being maintained. I'm sure those support contracts are very costly! IBM still makes their Power Series servers using their Power microprocessors as Oracle still makes Sun SPARC servers.
Mid 1970's: - I was in high school in O.C. S.CA and signed up for a BASIC class on our districts time share system. When I logged in, the response was "HATS OFF TO YOU". HATS was "Huntington Area Timeshare System." I later took an APL programming class at Golden West College. Useless today, but fun stuff ;-)
ught several such systems from us as did all the auto manufacturers.
Early 1980's: - We used DEC microPDP-11 that used LSI 11/73 Qbus card in a card cage. We ran DEC RT-11 OS. This was part of an automated printed circuit board 'router' which laid out the best path for circuit board traces and generated a Gerber file. The file is then sent to a shop that manufactures the circuit boards.
Somewhere in there I played around with a Z80 based CP/M system, 6502 microprocessor KIM-1 board with HEX pad, and a 6502 based Apple II clone. The RS TRS-80 was very popular back then and I think Heathkit may have offered them or a similar Z80 based kit.
