Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Path: utzoo!mnetor!uunet!seismo!husc6!think!ames!lll-tis!ptsfa!varian!madvax!cw From: cw@madvax.UUCP (Carl Weidling) Newsgroups: comp.arch Subject: An old fashioned memory technology, CRT's, how'd they work? Message-ID: <602@madvax.UUCP> Date: Mon, 13-Jul-87 16:22:38 EDT Article-I.D.: madvax.602 Posted: Mon Jul 13 16:22:38 1987 Date-Received: Wed, 15-Jul-87 01:25:37 EDT Organization: Varian Instruments, Walnut Creek CA Lines: 19 Yesterday I bought a book called "Bit by Bit, An Illustrated History of Computers", by Stan Augarten,Ticknor & Fields,NY,1984. It seems like a good book from what I've seen glancing through it, but, I was reading about the design of the Mark I in Manchester,England where it says: "He [F.C. Williams, the project's chief engineer] hit upon the idea of employing ordinary cathode ray tubes [to solve the problem of internal memory storage]...Their operating principle was quite simple; "guns" in the bases of the tubes shot positively and negatively charged electrons at the faces of the tubes, thus storing bits in the form of charge spots, which, by the way, were quite visible to the eye." Well, I have a problem with "positively and negatively charged electrons", but also, with how this can be memory. How long did the charges last? were they refreshed? How was the memory read after being stored? If anybody out there knows this stuff, I would be appreciative if you could enlighten me. My limited impression is that the book is better than this little excerpt would make it appear. Regards, Carl Weidling