Date   : Mon, 12 Dec 2005 18:34:02 GMT
From   : Pete Turnbull <pete@...>
Subject: Re: BBC B with a black power cable

On Dec 12 2005, 12:51, Littlefield Aaron wrote:
>
> I've just won a BBC micro on eBay that has a black power cable.
> Does this signify an early Model B (or even a Model A)?

Normally black cables are only on the old black linear power supplies,
but they were used on a few Bs as well as As.  This one looks newer
than that (fairly smooth plastic case rather than somewhat rough
textured), and it says it has a "DFS board" -- well, Acorn provided
switch-mode suplies to replace linear ones free of charge if you had a
disk upgrade.  I'd guess the cable has been changed for some reason.

Slightly curious about the "DFS board"; it's not normally a board.  I
expect it's a non-Acorn DFS that has the FDC chip on a carrier, but it
might be a 1770 DFS.

> It hasn't arrived yet so I can't test the machine out and look
> for tell-tale signs, but it also appears that the square ROM socket
> on the left hand side of the machine isn't there (unless it's taped
> over).

There isn't normally a ROM socket (or anything else) at the left hand
side, and what you see in the picture is perfectly normal.  There's a
section of the black trim that can be removed, intended to give access
to two edge connectors that could be fitted on the keyboard as part of
a speech upgrade.  Sometimes people fitted a ZIF socket for a sideways
ROM in the hole instead.  The removable section was a bit too easily
removable on early versions, and it was colloquially known as "the
ashtray" as a result.



-- 
Pete						Peter Turnbull
						Network Manager
						University of York