> On Mar 8, 2023, at 8:31 AM, Jon Elson via cctalk <[email protected]> > wrote: > > On 3/7/23 22:34, Zane Healy via cctalk wrote: >> >> I’ll be the first to admit my question is a bit strange. Basically I’m >> trying to use the date that various media types were first introduced to >> show the oldest possible date for a bunch of media I’m trying to date. The >> 9-Track tapes have been inventoried as “700 6250 BPI”, and I know they’re >> the smaller reels. Doing some digging, it looks like 6250BPI tapes date >> back at least as far as 1971 with the IBM 3400 series drives, I’d thought >> that 6250 came about in the 80’s. > > Wow! I'd love to see the 1971 vintage GCR tape controller, it must have been > the size of a 360 CPU! We had a GCR controller from Storage Tech. in 1982 or > so that was the same size as a PDP 11/44 large cabinet. CDC Keystone drives > (92185) had it integrated into the 680x controller micro, which I thought was > pretty amazing. > > Jon >
https://www.ibm.com/ibm/history/exhibits/storage/storage_3420.html It turns out that it was the 3420 models 2, 4, and 6 that were announced in March 1973 that supported 6250. Zane
