It was long ago, but I used 3420 tape drives frequently. (And also IBM 7330 tape drives, which were slower, smaller, and less expensive). As best I remember, a 3420 did not produce any significant heat --- especially when it was idle. When a tape was mounted, there was some extra energy that went into the vacuum column operation. My memory is too faulty now to recall whether three phase electricity was actually needed by the 3420. The control unit was a different animal in terms of energy.
Even then, I was impressed by the mechanical operation that could, in about .25 inches, start moving the tape at 120 inches/second (if I am remembering this correctly). Or, conversely, stop a tape in about the same distance. All without any damage to the tape. Some reels of tape were reused hundreds of times. I remember, in rarer instances, throwing away about 100 feet of tape and placing a new sensor strip on the tape. One item that would be important, especially in a normal work environment, is rather frequent cleaning of the heads. Slightly off topic, but I wonder if the disappearance of basic, "old style" tape drives (or maybe 3490-type cartridge drives) from mainframe floors is a completely good thing. Sometimes a simple "hands on" tape drive was useful for systems-programmer type people!! Bill Ogden * ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN
