VAXen at home
ajp166 at bellatlantic.net
Mon Oct 15 19:25:45 CDT 2007
>Subject: VAXen at home
> From: ard at p850ug1.demon.co.uk (Tony Duell)
> Date: Mon, 15 Oct 2007 23:21:05 +0100 (BST)
> To: cctalk at classiccmp.org
>> > So you want me to start off with a VAX?
>> Lots of folks on this list have lots of nice things to say about the 11/750.
>Personally, I theink the 11/750 is not the best machine to try to keep
>running. The reason is that the CPU is made up of a large-ish number of
>custom gate array chips. Even when they were available as spares from DEC
>they were very expensive, now they're unobtainanle other than by raiding
It's not that bad, lots of spares out there this side of the pond.
It's a nice system as it's fast enough to be useful and while a
big VAX it's not a huge vax like 780 or 8650. That and there were
a fair number of machines kept in service that were supported.
>If you have the space (and it's large), try to get am 11/780. I've never
>been inside one, but I've read the printset (schematics) and it seems to
>be all standard chips.
The air handlers and the power will get you. It's a very nice well
ordered machine in many ways.
>If you don't have the spave, and can stand the lack of speed, consider an
>11/730. It's small (1 10.5" high rackmount unit), you can fit the
>processor, disk and tape drives into a half-height rack (this was a
>standard configuration). It's almost all standard chips, 2901 ALUs, TTL,
>non-protected PALs, etc.
The only thing is a 730 is hard to expand to run fairly current VMS
and it's slow. For that performance you can get a lot of other VAXen.
It's up side is for one rack it's small and power consumption is
within the realm of a 20A at 120V circuit with some of the smaller
single cab version down near 12-13A at 120V.
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