VAX-11/730

On 4/19/05, spedraja at ono.com <spedraja at ono.com> wrote: There were two styles of 11/730, one with the CPU in the middle of a 42" cabinet in its own 10.5"-tall drawer, and disks above and below (the most common configuration was an RL02 on top and an RB80 (121MB pseudo-SMD drive) underneath), and one with, IIRC, a BA-11-type drawer at the top of a 42" cabinet, and cable management space below (and no disks in the CPU cabinet). I used to have one of the first type, and have never seen the second type except in pictures. The 11/730-Z (first type) has a backplane limited to 5MB of RAM, with room for a couple of other internal peripherals. A common add-on was a DMF-32 (8 async, 1 sync, 1 printer). The RL02 and RB80 were run DQA1:. The machine is Unibus-only, and it _is_ possible to run a Unibus cable out and to an ordinary BA-11 with DD11-DK backplanes and the like. Being Unibus, one can attach 3rd party ESDI, SMD, and SCSI controllers, but I dare say you'll have quite a time locating an inexpensive Unibus SCSI controller. It can talk to a DEUNA or DELUA Ethernet interface, but either of those might draw too much power to mount internally. Same goes for a UDA-50. The only compatibilty issue is power draw. If you have an external BA-11, you are good to go for these power hogs. You'll need a boot cartridge with this - just like the VAX-11/780 powers up stupid, the 11/730 does as well. Where the 780 has a PDP-11 processor that loads up microcode and boot images and whatnot from an RX01 floppy, the 730 has an 8085 that loads things up from TU-58 tape. Check your tape drives for gooey capstans. If the rubber seems like it's melting or turning into something that resembles a black jellybean, do *not* mount tapes. You will have to refurb the drive first. Tygon aquarium hose from the hardware store (.500"?) works well for this. Your boot tape has to match the OS you'll be running - there were tapes for VMS and tapes for Ultrix. I presume there were also tapes for BSD, but I only ever ran BSD on 11/750s, not 11/730s. The 11/730 (and 11/725) CPU rivals the MicroVAX-I for slowness (one is 30% as fast as a 780, one is 40% as fast), but is a solid machine. We used to use ours at work first for an office machine (MASS-11 and VMS MAIL) for a satellite operation, and later for a VMS 5.0 link machine for software development. It would run for months at a time without problem. The max memory is a bit limiting; I would be surprised if you could run VMS 6.x on it, but I know VMS 5.0 runs. It was developed in the days where 2MB-3MB would suffice for a system with a small number of users, and was more-or-less rendered obsolete with the coming of the MicroVAX-II about 4 years later, with up to 16MB of RAM, a faster processor, 5.25" disks, and a much smaller box (but not a much smaller price tag, only slightly smaller). Good luck with it. If you want to play with a Unibus VAX, it's the second smallest one, and not bad for a single-user VMS 4 or VMS 5 system. Hope some of this helps, -ethan