Ames Laboratory, Department of Energy, ISU, Ames, Iowa

|| Early Photos || Photos of Progress || ABC Diagrams ||

Early Photos

John Vincent Atanasoff
(circa 1983)
Clifford Berry

He invented the idea for the computer
in the mid 1930s.
Graduate student who did the actual
construction of the computer.

Physics Building at Iowa State University

In the basement of this building is where the computer was first created in 1939.

Clifford Berry with the ABC

Photos of Progress

Large (1280x960) photo of completed replica over the front-left corner

Large (1280x960) photo of completed replica looking directly at the front

This drum holds 30 numbers of 50 bits each. (Two of the
columns are spares). They are operated on in parallel. It is the first use of the idea we now call "DRAM" -- use of capacitors to store 0s and 1s, refreshing their state periodically.

It is the only surviving fragment of the original ABC built in 1939.

Jerry Hand turning components for the computer on a lathe.

Steve Lee cutting parts for the computer on a computer numerically controlled (CNC) milling machine.

Frame with card reader.

Front view of frame with base two punch/reader near a door similar to 1939 photo of original.

Left-front view of frame with base two punch/reader near a door indicating approximate height of frame

Base two punch/reader viewed from front-center as operator would see it.

Close view of base two punch/reader from left of frame.

View of base two punch/reader from right end of frame.
There was no tray to receive cards. A person had to catch them. They came out 1 per second.

View of base two punch/reader from left-rear.

Close view of base two punch/reader from left.

Gary Sleege entering ABC circuit components into Electronic CAD to create ABC schematics. 1995.

FOREGROUND: Model computer and ASM under test.
BACKGROUND: Model computer control panel and ASM schematic.

FOREGROUND: Model computer view from the right side.
BACKGROUND: ASM under test with model computer.

Model of ABC built for use during trial.

John Erickson holding purchased vacuum tubes manufactured in the 1940s for use in the ABC.

FOREGROUND: Old parts acquired for construction of ABC (note vacuum tubes and connector from the 1940s, telephone switches and panel meter).
BACKGROUND: Newly constructed ASM chassis.

FOREGROUND: Newly constructed base two punch drive electronics.
BACKGROUND: Newly constructed base two punch high voltage transformer chassis.

FOREGROUND: Newly constructed Add-Subtract Module (ASM) showing seven vacuum tubes (6C8).
BACKGROUND: Bottom view of newly constructed ASM being tested with connection to model computer.

Original card punch Model #010 that punches decimal coefficients for input into ABC.
Courtesy IBM.
If you know where to buy one, please send e-mail.


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