14 Dec
2007
14 Dec
'07
3:27 a.m.
Robert Nansel wrote:
I'm looking at what it would take to make a
barebones "museum piece"
bit-serial computer along the lines of an LGP-30 or maybe a Bendix G-1
So I am not the only madman araound here !
I was thinking around a transistor based cpu with homestring core
memory. I happen to have ca 5000 TO-5 cans with a dual transistor each,
and Si diodes are cheap.
And the keep the project within budget (i.e. none to
speak of),
That is, I believe, a recipy for disaster. Your really need to budget
for having PCB's made if you want some reliable operation of whole cpu.
Ond you will probably have to give out work to a machineshop.
I've scavenged the web for information on
bit-serial magnetic drum
machines of the Elder Years, and I think I have a pretty good notion of
how they worked (mostly very slowly).
To prove this to yourself it is always a good idea to build an emulator
in C.
What I haven't been able to get a
handle on is how to make a serviceable magnetic drum.
A major mechanical challenge, I believe outside most people's
capabilities. Tony is bound to comment on it though !
Certainly I could trash a few old cassette decks,
A local electronics shop has hundreds of unused cassette heads, each
time I pass I think " line up 100 of those and make a drum".
Sanity comes back quickly though.
Major problem in this kind of constructions is to keep your interest
going on long enough, and have enough time to see it through.
A couple of years ago the German CT magazine had a nice article about
how, in the early sixties, some German universities were creating
exaclty this kind of drum machine for their own use. This article is on
http://www.billingpreis.mpg.de/hbp05/gewire.pdf
(Sorry, German only )
Jos Dreesen