You could remove the disk from your Ultrix box, install another diskand install NetBSD. The Pmax version works on the DEC MIPS boxes:http://wiki.netbsd.org/ports/pmax/. You could also do that on your DECAlpha. The TK50Z should be a SCSI drive, you could also just move the drive to another UNIX/Linux/BSD box
It's been a while since I played with any of my vintage computers that have a TK50 drive. Could it be that the SCSI controller / bus in the Ultrix box isn't fast enough to handle the tape drive at "full speed"? You could try putting the drive on a modern computer with a modern SCSI controller with nothing else on that SCSI bus. Ten plus years ago I was working on a satellite ground system and we needed to record the real time down link so we could use it to test the system. The data was written to a SCSI DLT drive. The speeds listed for most tape drives are peak speeds, and it was very hard to get a sustained data rate that was close to the peak data rate listed by drive manufacturers. Robert -------------------------------------------------------- Is there a dd equivalent for VMS? Background: I am trying to recover some TK50 tapes that were written on Ultrix. I have a MIPS machine with Ultrix 4.5 on it and a TK50Z drive. I have been able to read some tapes but they all seem to get an I/O error after a while of reading. I think this could be due to the accumulation of oxide on the heads. Despite cleaning the heads after every tape (by disassembly and cleaning with isopropyl on a cotton bud). I think the oxide is accumulating more than necessary because of the poor streaming abilities on the TK50 drive (too much back and forth over the same section of tape). I do have more modern drives (TK70, TZ85, TZ87 etc), but Ultrix does not seem to recognise them. So I was hoping to use one of my VAX or Alpha machines with VMS and a better tape drive to recover the raw data. Ideally I would like to make a SIMH virtual tape clone of the real tape. Any other alternative suggestions very welcome.
