Date   : Sat, 19 Sep 2009 01:43:03 +0100
From   : theom+news@... (Theo Markettos)
Subject: Beeb, this was your grandma!

Rob <robert@...> wrote:
> On 18/09/2009, Rick Murray <rick@...> wrote:
> > Greg Cook wrote:
> >
> >> I was just forwarded this link, and it's simply awesome.
> >> http://www.bbc.co.uk/archive/tomorrowsworld/8008.shtml
> >
> > Helping hand, please? "Not available in your area".
> 
> It's about school kids learning about the mainframe computer installed
> in their school, adding in binary, repairing the thing (12 hours
> uptime average) etc..

There's some kind of rotary convertor in the garage. There's 'disc' and
'oil' involved as well as paper tape, and the output is displayed as a trace
on an oscilloscope or a typewriter (no CRT).  There's 'HT' which suggests
some valves.  The thing has diodes going wrong frequently.  The front panel
is just lights and switches, while the cabinets occupy a good-sized room. 
It looks like a commercial unit rather than a university leftover.  At
Forest Grammar School (in Winnersh, Google tells me).

I did some digging, but couldn't find any real ideas what sort of machine it
could be.  It looks fairly primitive, and with the diodes I think it might
be using DTL, so I'd imagine late 1950s?  10 years is the sort of time at
which a corporation would have replaced it with a new machine (bearing in
mind these were seriously expensive).

The unit with the most physical similarity I can find is the PDP-1, but
that's a bit too modern.  And I imagine the Forest School computer was
British.

Theo