On Fri, 7 Apr 2006, Kim Hawtin wrote:

> Hi guys,
> 
> I have a MicroVAX 3100, but I am unsure of which model ...
> 
> On the back, it has a model number of; DV-31ETA-A-A01
> On the bottom of the case it has; Series BA42B & CPU KA41
> 
> I've google a bit but have no obvious link between these numbers and the
> human readable model number, like say; 3100/80.
> 
> Any ideas?

I think some people here speak the language of DEC model codes
fluently, and will perhaps give you an exact answer.  Meanwhile,
here's some of what I know...

I think the "BA"-number refers to the physical enclosure of the
machine.  The "KA"-numers are much more common and are used to
refer to specific VAX CPU modules, although that scheme is
almost never seen in VAX literature from DEC or 3rd parties.
I've noticed that they sometimes correspond to the value in the
"Id" column of Paul Hardy's CPU model summary, which is
available from:

    http://www.hardy.demon.co.uk/paul/programs/vms_cpus.html

For example, my VAXstation 4000/60 is a KA46.  My guess is that
yours is one of the CVAX-series MicroVAX/VAXstations:

...Id....VUPs...Model name.....................Nickname
---- CVAX chip series (1987) - SID = 167772160 ------------
   420   2.8    VAXstation 3100 models 30, 40  PVAX
   420   2.4    MicroVAX 3100 models 10, 20    Teammate II
   420   3.5    MicroVAX 3100 models 10e, 20e  Teammate II
   420   3.8    VAXstation 3100 models 38, 48  PVAX rev#7
---- Rigel chip series (1990) - SID = 184549376 -----------
   43    7.6    VAXstation 3100 model 76       RigelMAX
   43?   7?     MicroVAX 3100 model 40         ??
---- Mariah chip series (1991) - SID = 301989888 ----------
   1202  13-58  VAX 6000 model 510-560         Calypso/XMP
   46    12     VAXstation 4000 model 60       PMariah
   46    12     MicroVAX 3100 model 80         Waverley/M
   46    16     MicroVAX 3100 model 85, 88     Waverley/M+
................

-aw