IBM 1401 40-28588 2151_788 ALD drawings

The file

1_1 Logic Diagrams 1401_40-28588 2151_788.pdf

contains the first- and second-level logic diagrams for an IBM 1401 computer having serial number 28588, which I think is the one at the Australian Computer Museum. The files

1_7 SDI-Plug Charts + Power Supply 1401 40-28588 2151_788.pdf

2_7 1401 40-28588 2151_788 21-32.pdf

3_7 1401 40-28588 2151_788 34-35.pdf

4_7 1401 40-28588 2151_788 36-41.pdf

5_7 1401 40-28588 2151_788 42-44.pdf

6_7 1401 40-28588 2151_788 46-99.pdf and

7_7 1401 40-28588 2151_788 TAU.pdf

are the files for the third-level, or ALD, diagrams.

I think I found them all somewhere at (or maybe at They are scans of the set of CE books that came with that computer. I've split them into individual drawings, one per file, mostly one page each, although some are several pages because there are consecutive pages in those files that have the same drawing number.

I've separated each of these files into individual "drawings," and put all the drawings from each of these files into a directory named 1_1, 1_7 .. 7_7 to correspond to the file names.

Each drawing has a file name that is the same as the drawing number stamped at the bottom right of the image and printed at the top left of the image, with the extension .pdf.

Almost every one of the ALD drawings is also identified by a "logic number" of the form To cross-reference these identifiers, I've created a soft link (shortcut in Windows) from the drawing number to the logic number. So drawing 1_7/729049.pdf is also identified by 1_7/

I also made a list of the correspondence of drawing numbers to logic numbers, including the drawing title, the frame/channel location, and the page number in the original file. In each directory, this is in a plain-text file named List_*_7, where *_7 is the same as the directory name.

I've put all seven lists together into a single file and sorted it five ways, book/page number, drawing number, logic number, title, and on frame/channel then logic number then title. These files are named List_1_7-7_7, List_1_7-7_7-alpha, List_1_7-7_7-dwg, List_1_7-7_7-FR_CH, and List_1_7-7_7-logic. I've bundled these files into gnuzip-compressed tarballs, which WinZip understands.