Distrowatch

[Tony Arnold]

On Wed, 2005-04-06 at 09:15 +0200, Vincent Trouilliez wrote:
> > University of Manchester (UK) back in 1949. It was known as Mark 1, used
> > valves and cathode ray tubes to store the programs.
> 
> Wow, CRT's to store data ? The oldest memory I knew of were the matrices
> of tiny magnetic tori (my ancient electronic teacher at the time, dug it
> out of his personal "museum"... ), but CRT's, it's probably even older
> technology... I wonder how it works...

Not sure exactly how it worked but the cathode ray was used to put a
charge on the surface of the tube. There was also a plate over the front
oc the tube which somehow detected the presences or absence of charge
when the electrons hit it. The charge dissipated from the surface over
time, so the memory was constantly being refreshed, a bit like dynamic
RAM today!

Storage was small. Of the order of about 32 rows of 40 bits per tube!

The storage mechanism was invented by Freddie Williams and was known as
the Williams Tube. My previous reference www.computer50.org has some
details.

Regards,
Tony.
-- 
Tony Arnold, IT Security Coordinator, University of Manchester,
Manchester Computing, Kilburn Building, Oxford Road, Manchester M13 9PL.
T: +44 (0)161 275 6093, F: +44 (0)870 136 1004, M: +44 (0)773 330 0039
E: tony.arnold at manchester.ac.uk, H: http://www.man.ac.uk/Tony.Arnold