"Bob" Erickson provided the following IBM-603 document.
(10.5 MByte) Also in parts, see below.

The IBM 603 was IBM's first fielding of vacuum tubes to perform arithmetic in office equipment.

The problem of mechanical multiplying in the short (tens of milliseconds) time interval for effective use in tabulating equipment was solved by replacing relays with the far superior switching speeds (more than a factor of 1,000) of vacuum tubes.

IBM provided this manual with very thorough description of the practical workings of the electronics of this machine. This enabled the IBM Customer Engineers, already familiar with relays and gears, to enter the age of vacuum tube logic. This document, along with Navy manuals, provide the reader with a very easy to follow series of steps in the understanding of vacuum tube logic - the dominant logic for 8 years until transistors developed into the rugged, cheap units that were dominant from about 1959 for 10 years. (The early IBM 360 logic was still discrete transistors in a group in a smaller package.) About 1970, transistors got "integrated" resulting in the very size reduced technology we still use today - 2005.

This resulting IBM 603 had a production run of 100 units to get field experience with these non-mechanical units. Bob Erickson was one of the Customer Engineers trained on this equipment, and serviced it in the field. Evidently IBM was satisfied with the experience, and the IBM 604 was soon produced which performed all arithmetic logic - addition, subtraction, multiplication, and the more difficult division - all with vacuum tube logic.

For convenience for folks with slower communications, the following parts are provided:

TOC & Introduction ( 0.5 MBytes)
Mechanical Principles ( 1.8 MBytes)
Adjustments ( 0.8 MBytes)
Electrical Principles - a ( 1.6 MBytes)
Electrical Principles - b ( 2.0 MBytes)
Electrical Principles - c ( 1.8 MBytes)
Electrical Principles - d ( 1.3 MBytes)
Testing Procedure and Trouble Analysis ( 0.85 MBytes)

Please note that the Table of Contents of the complete form (10.5 MBytes) of the document has had links placed in it. Clicking on a boxed link will quickly move the view to the proper page.

To use the ADOBE "BACK" function to get back to previously viewed pages.

As stated by Paul McJones:" The 'back' button is there, but in a slightly non-obvious place. At the bottom of the Acrobat window is a horizontal area containing the current page number, and icons for moving to the beginning, back one page, forward one page, and to the end. "To the right of these are a pair of green circles containing white arrows, pointing left and right. The left arrow is 'back' and the right arrow is 'forward', within Acrobat's 'history'. So they function pretty much the same way as the green 'Back' and 'Forward' in a web browser."

Enjoy this rare, ground breaking IBM-603 document.

Ed Thelen (scanner)