3M cartridges can be either restored or the data read from them, about 15 years ago I took on a project to recover data from about 200 DC-300 cartridges.
The key is test and remove/replace the elastomer band before using the cartridge. But if one does get the remains of the band all over the place it just adds to the recovery time. There are two recovery methods, the first is to replace the band. Pretty much find a band from a DC600 or new cartridge. If that does not work one could look into having a band made. Even if it is for a one shot attempt to get the data off the tape. There are (were?) companies that make belts. They grind the ends in a taper then bond the ends together. Another is to jury rig a drive to read from tape but not in the cartridge. This is what I ended up doing. Try to image a real to real tape machine. Again the idea is just to be able to read a tape once to recover the data. Not to re-create a full transport. Your going to need the resources of a small machine shop but depending on the drive your going to sacrifice it not that hard to do. The drive I had was one where the cartridge loaded sideways. or the smaller end in first. You first built/find two servo/tension drives to hold each of the two spools. The servos job was to keep tension on the tape going into and out of the cartridge. The cartridge was modified to spool tape out and in, and to keep tape under tension between the head(s) and the capsin. For servo's I took apart semi-pro 1/4" tape transport that had servo driven tape reels. That machine also got me tape guides and rollers. Another task is removing any band remains from the tape with solvents that will not effect the bond between the tape carrier (plastic) and the magnetic material. It was a long time ago but I remember either isopropyl or ethyl alcohol. On Wed, Jun 1, 2016 at 7:02 AM, Rick Bensene <[email protected]> wrote: > Hello, kind ClassicCMP denizens, > > I have two old Tektronix workstation machines. > > One is a Tektronix 4132. It is a pc-sized (a little less tall, a little > deeper) unit that uses a National Semiconductor 32016 chip as the CPU. It's > got a bunch of cards for RAM expansion, parallel and RS-232 ports. It comes > with two built-in RS-232 ports, one of which is for the console terminal. > These machines have a slot in them a SCSI (single-ended) drive. Typically > they were equipped with Maxtor XT1105 and XT1140 drives. In the front, they > have a tape cartridge drive that uses 3m DC300A data cartridges. This drive > is equipped with a piggy-backed Adaptec converter that takes the native QIC > tape drive format and converts it to a SCSI accessible tape drive. On the > bank panel is a 7- segment display that indicates the self-test and > diagnostics, and when the OS (UTek) is loaded indicates system activity. > These is also a row of DIP-switches that set things like the console baud > rate, boot device, and stuff like that. There are two DB-25 serial ports, > a GPIB port, an AUI port for 10 Megabit Ethernet, and a port that extended > the internal SCSI bus externally. Below the back panel are slots for > plugging in options such as RAM and I/O, which included things like > full-width RAM cards (2 MB I think was the largest), half-width dual-port > async RS-232 serial cards, a half-width parallel interface card, a half-width > SCSI interface card (added another SCSI interface to the machine). The > machine ran a 4.2-Berkeley variant known as UTek. > UTek was installed on the machine by putting a special cartridge in the drive > that contained essentially a miniroot filesystem and basic boot code. The > configuration switches on the back would be set to force the tape drive as > the boot device. The machine would be powered up (the power button was a > soft-power switch on the front panel of the machine), and the tape would be > read, and options provided via the console terminal to format the drive, set > its partition table, and things like that. Then, the mini-root Unix system > would be loaded into, and run out of memory. From there, if I remember > correctly, there was another cartridge (or perhaps two) that had the full > UTek installation on them. The first tape was loaded, and a script run from > the mini-root OS that would begin the process of loading UTek onto the hard > disk from the tape image, and creating the boot block and all that would be > needed to boot up the full UTek environment from the hard disk. When > complete, the scripting would ask for things like setting the time and date > (the machine had an built-in battery-backed real-time clock/calendar), > setting the root password, creating user accounts and groups, and stuff like > that. > The machine was (for the day) a pretty capable little Unix workstation at a > time (the 4132 was announced in August of '85) when Suns were still at > Berkeley, and anything else that ran a halfway decent version of BSD was a > supermini like a DEC VAX, some of the more powerful PDP 11's, or a Gould > PowerNode. > > The other machine, the Tektronix 4317, was again a Unix workstation-class > machine, but this time, was based on the Motorola 68020 CPU, likely because > software availability for Motorola 68K-family machine was much higher than > that of the National 32016/32032 architecture, and porting things proved to > be quite a difficult thing to do. > The 4317 was also in a PC-like cabinet, with a QIC-type tape drive on the > front. Internally, a SCSI hard disk provided storage, typically a larger > one, like a 300Mb drive, from various different manufacturers. The back > panel was similar to that on the 6130, though the SCSI connector was more > standardized, and there was an option for a framebuffer card that could add > on to the CPU that provided graphics capability. BNC connectors for RGB and > sync (IIRC...or maybe it was sync-on-green, can't remember) were there, along > with a jacks for plugging in a keyboard and mouse. With a color display and > keyboard/mouse the machine could run X-windows. The back panel also had > RS-232 ports, GPIB, and, if I remember correctly, it had both an AUI and BNC > (for thin-net coax) for 10 Megabit Ethernet. It had some slots for expansion > options, but I don't remember how they were organized. The CPU board had > quite a bit of room for RAM, and I believe a RAM expansion board could pop > onto the main board to bring the RAM (without expansion slots) to something > like 4 or 5 megabytes. > > Anyway, the situation is this: > > I've got a 4132 and a 4317 stashed away in storage. Both machines have had > hard disk failures, so OS is gone. > I used to have installation media, but alas, the cartridges all suffered > failed drive tapes, and they failed in a way where they turned into goo, and > without noticing it, I put them in the drives, and the goo turned to tapes > into sticky, goopy spaghetti, not to mention making a mess out of the tape > drive head, and getting gooey junk all over the capstan and metal tape > guides. They weren't salvageable in any way. > > So...what I'm looking for, after all that (hopefully informative) verbiage, I > am wondering if anyone out there may have original UTek distribution media > for both the 4132 and 4317 (may also work with the 4319 media), on DC300 or > DC600 cartridges that are still viable, or at least if someone out there may > have imaged said media somewhere along the way. I figure that with a good > drive, I could reconstitute the images such that I could potentially get > these two machines running again. I have appropriate SCSI disks that will > work with the machines, and both machines seem to pass the in-built > diagnostics and get to the point where they want to boot....but, alas, > there's nothing to boot. > > Any help is greatly appreciated. I have had these machines for a long time, > and the 4132, I actually built from parts purchased from Tektronix stock > when I worked there. I ran it for a long time, until I could get a PC that > was a lot faster, and run (sigh) Windows, for very little money. I even > still have 8mm backup tapes from the things...but only user data, not full > backups of the OS and all. > > Thanks in advance, > -Rick > > --- > Rick Bensene > The Old Calculator Museum > http://oldcalculatormuseum.com >
