23 Feb
2003
23 Feb
'03
1:21 a.m.
Does anyone on here know anything about a digital computer demostrator unit made by IBM
in the late '50s? It's housed in a nice wooden box about 2 feet wide x 15"
deep x 12" tall. On the top of the box is a brass plaque that says "Presented by
International Business Machine Corporation". Inside is a grey painted metal box with
a row of ten 9-pin tube sockets along the back of top. In front of each socket is a single
nean light. In front of that are blocks with small holes for jumper wires similar to those
used in the Heathkit trainers. One end of the box has a male Jones plug connector and the
other end has a female connector. It looks like the units were made so that additional
units could be stacked together. On the front side of the grey box is a tag about 1
1/2" x 3" that says IBM in large letters. In a compartment on the right side of
the wood case is a power cable that plugs into one of the Jones plug connectors. Under the
grey metal chassis is a compartment with jumper wires, spare neon lamps and other small
parts. Along the front edge of the box are two rows of holes that hold modules that plug
into the sockets in the metal chassis. Each module is an open chassis about an inch square
and 4 to 7 inches tall. Each chassis has at least one vacuum tube in it and some have two
tubes, one above the other. Each chassis has a metal hoop or bail that goes up and over
the top of the top most tube and back down the other side to form a handle for inserting
and removing the chassis. On the top of the bail is a small tag with numbers like
"TR-2", etc. Besides the tubes the chassis also have other small components such
as resistors and capcitors. There are a total of twenty of the small chassis and each one
can be plugged into any of the sockets in the main unit but you have to set a number of
jumpers on each socket to a get the correct voltages for each of the tube elements. The
tubes can be configured as logic elemements such buffers, invertors, various gates, etc
and they jumpered together to form more complex d
e
such as flip flops. Evidently the nean lamps are used to indicate the state of each logic
element. The guy that had it was quite specific and said that is is NOT an analog computer
but a digital one. I went through it trying to find a model number or date but could only
find the number 56 stamped on some of the tubes. I'm not sure if that's the
manufacturering date or not but it's probably close.
Can anyone tell me more about this thing or even (HOPEFULLY) have a manual for it?
PS this came from the University of Florida.
Joe