----- Original Message -----
From: <carlini@bulean.lkg.dec.com>
To: <port-vax@netbsd.org>
Sent: Thursday, March 30, 2000 3:49 PM
Subject: Re: A couple of Vax 'problems'


> I'm shocked to find that I don't have their dimensions on hand but the
RA82 is
> about the width of the BA213 cab and maybe 30cm high. The RA90/RA92 is
the same
> height and half the width (i.e. you can get about two RA90s in the
space for an
> RA82 - at least visually, physically you probably find the mounts are
all
> different).

They do have somewhat different mountings, however the 2 x RA9x to 1 x
RA8x is correct.

> They're pretty scary weight-wise too: I can only guess at the weight.

RA8x drives weigh around 64Kg each.  I can just manage to pick up and
carry one at a time.
Ra9x drives are around 30kg each, and somewhat easier to handle!  It's
feasible to run a few 9x's
on a hobbyist system, RA8x's are somewhat heavier on power, and pull
quite a few
amps spinning up those huge platters.  And they are NOISY, even when
they are working well.
Somewhat unreliable too, the spindle bearings have a habit of taking a
dive due to the high tension
on the drive belt.
If you have to get drives, try and get some RA7x series.  They are
house-bricks and fit four to
a mains powered SA70 housing.  2 x SA70's (8drives) fit comfortably in
the space taken by a single RA8x.
Power requirement for 4 x RA7x is about the same as a single RA9x.
I presided over the dismemberment of an RA81 today.  I'd say a very nice
clock face could me made from one of the platters, and I'm contemplating
a chart recorder for the voice coil assembly....

Cheers

Geoff Roberts
Computer Systems Manager
Saint Mark's College
Port Pirie,
South Australia
geoffrob@stmarks.pp.catholic.edu.au
netcafe@pirie.mtx.net.au
ICQ: 1970476

Hope this helps.