Thanks, Ethan. This information is helpful by now.
Cheers
Sergio
-- Mensaje original --
Date: Tue, 19 Apr 2005 05:14:06 -0400
From: Ethan Dicks <ethan.dicks at gmail.com>
To: "General Discussion: On-Topic and Off-Topic Posts" <cctalk at
classiccmp.org>
Subject: Re: VAX-11/730
Reply-To: Ethan Dicks <ethan.dicks at gmail.com>,
"General Discussion: On-Topic and Off-Topic Posts"
<cctalk at classiccmp.org>
On 4/19/05, spedraja at
ono.com <spedraja at ono.com> wrote:
> Hello everybody. I'm in the process to obtain one VAX-11/730. In appeareance
> in working condition. I'm only waiting to know if it comes in "tower"
> with a couple of RL02 units or not. Having this
last in mind, I would
comments about
the possible expansion of the system with other options:
storage
(9-track unit(s) or Disks in SMD or SCSI format),
memory, connectivity
(serial
and network ports, signal control ports), etc. If
I remember well this
machine
only had Unibus and not Massbus.
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
from a special disk card in slot 1, and appear to VMS as DQA0: and
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