From:	HENRY::IN%"SYSRUTH%utorphys.bitnet%wiscvm.wisc.edu%kl.sri.COM%relay.cs.net@RCA.COM" 25-APR-1987 11:57
To:	info-vax@KL.SRI.COM
Subj:	VAXstation II/GPX and options

VAXstations are a little tricky for adding options since DEC has very cleverly
filled half the bus slots with glue. The simplest and cheapest way around it
is to buy and expansion box, which is about $3000 (Canadian). It has a couple
of cards with a cable that come with it, and we have and RC running now with
this setup. You may have to wheedle a bit with your sales rep to get one -
DEC hates selling them. You may find an OEM in your area who might have a
couple. Or there is a third-party box we are about to test in the next couple
of days - I can let you know how it works out. Certainly DEC's own works just
fine. This pretty well means you need to rackmount it, but you'd probably
want to put the disk, and possibly the tape as well, in the same rack.
As far as disk and tape drive interfaces are concerned, you have lots of
third-party choices. We get our disk interfaces from System Industries (who
may get  them from Emulex). For system disks we use their QDA50's, for
others we use their 9900 controller. Tape drive interfaces we got from Aviv,
although SI also has the same thing. Note: these are multi-layered boards,
quite thick, loaded with components right out to the edges, and often not
easy to get in. But they work fine. Aviv has them for both STC and PERTEC
protocols; SI/Emulex may as well (although I'm told that STC is faster).
They use the standard DEC TSDRIVER. (Re disks: the QDA uses the standard
DEC DUDRIVER, 9900's use an SI driver).

The other alternative is to replace the backplane so that you have all the
slots available. This is cheaper, but much tougher both to do and to obtain
the parts for. The backplane costs about $500, plus a couple of hours' labour
(and manual-poring). However they are almost impossible to get. Last I heard
DEC was insisting on selling them only in lots of 50. So your only chance
here is OEM/VAR's, and still it's a long shot. I personally would recommend
going with the expansion box. It's cheap, it's easy, and it works. Running
cables may not be as neat and tidy as you might like, but it isn't a total
mess, either.

Any questions, just ask. Oh, the brand X box is made by a company called
Sigma. They also make a BA123-sized box that is *rack-mountable*.

And we run :-) *VMS* on *all* our uVAXes.

Ruth Milner
Systems Manager
University of Toronto Physics
SYSRUTH@UTORPHYS.BITNET

P.S. Those of you planning on being at DECUS next week - I've been trying to
find a time slot with nothing interesting in it. Maybe Wednesday at 6, after
all the sessions are over for the day? Discussion followed and/or over
dinner somewhere? Or I'll be there on Friday evening, as well. Any other
ideas? Please let me know - I would like to co-ordinate something. Check
under INFO-VAX on the message board if you don't see anything on the list.
Looking forward to seeing you all!