50 years ago I worked on a Honeywell computer that used a bank of 6 tapedrives. No disks. It would have been similar to these.
https://www.pinterest.co.uk/pin/536772849315564139/and
https://www.ebay.com/itm/1964-Press-Photo-Vintage-Honeywell-200-Tape-Drive-Computer-1960s-/202671838463The tape went from the reel down into a vacuum well, up to the tape head, down into another vacuum well and then to the takeup reel. Towards the bottom and top of each well were photocells that either stopped or started the movement of the reels so that the movement of the tape across the read / write heads was CLV and independent of the movement of the reels. They were very reliable.
Back in those days in Australia, it was standard practice to go to the pub each Friday for a boozy lunch. Eventually, I would get back to the office and have to make a decision about my ability to program. My test was to walk into the computer room and look at the row of tape machines while they were performing a sort. If I could work out what was going on by the movement of the reels, I stayed and went to my desk. Otherwise, I just staggered home. However, on Monday I would throw out whatever I had done on Friday afternoon if I had actually managed to produce anything.
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