Date   : Thu, 27 Oct 2005 00:00:44 +0100 (BST)
From   : Pete Turnbull <pete@...>
Subject: Re: Guess age from serial number?

On Oct 26 2005, 20:49, Kris Adcock wrote:

> I've got a Beeb here with the serial number 001013. It seems to be
> quite an early one - the power supply is one of the black variety,
and
> half the RAM chips are socketed. Unfortunately I can't see the issue
> number because a disk-controller daughterboard covers it.
>
> Anyway - anyone know if it's possible to guess an age from a serial
> number?

Well, that's a very low number, so that in itself tells you it's an old
machine.

All the early machines had a black linear PSU, so that's not too
surprising, though Acorn did try fairly hard to get them all replaced.
 There were, IIRC, three different types, and all were troublesome.
 One type was merely underpowered and didn't last well (or stay very
cool) in a fully fitted machine; others were less nice.  One was known
as the "adapter and exploder" because of a trait it sometimes exhibited
when overloaded.  I doubt many of those are left, somehow.

If half the RAM chips are socketed, that probably just means it started
life as a Model A, and someone has added the extra RAM.  I think all
the Bs always had soldered ICs (but my memory's been wrong before).

I once had serial number 6xx -- I think it was 672 or something like
that -- and it was a really early Issue 1 PCB.  It had quite a few
"engineering changes", as exhibited by several pieces of wire-wrap wire
to fix track errors on the underside of the PCB.  Issue 1s had quite a
few problems with sound, printer port, disc, video timimng, and many
other things.  Some upgrades (like the disc) just weren't worth doing
to an Issue 1, in the normal course of events.

Alas, my business partner loaned that machine to someone and we never
saw it again.

001013 might be old enough to be Issue 1.  If not, it's certainly no
newer than Issue 2.  Is the serial number sticker an orange ICL one
(that would be Issue 2) or a plain white one (could be Issue 1 or 2)?

-- 
Pete                                           Peter Turnbull
                                               Network Manager
                                               University of York