A bit of background:the ALDs (IBM 1401 schematics - Automated Logic Diagrams) which we received from Germany with the machine were: - the end result of many iterations of copying machines, - somewhat smudged, a little out of focus, many noise spots per page - and often really hard to impossible to read. So when John Dean in Australia said that he has a set of ALDs for a rather similar production model of 1401, Robert Garner sent encouragement and the cost of scanning the ALDs to CDROM. John Dean got the job done, made a nice index, and sent the CD to Robert.

Left: A "typical" clean Automated Logic Diagram (ALD) - on 11" x 17" sheet of paper

Right: Top of that page

The above look confusing?

- an overview picture is here
- Van Snyder suggests looking at IBM Customer Engineer Manual - Standard Modular System - Component Circuits a big 236 page .pdf manual

"I made some sense of the ALDs by having the SMS "book" 223-6875-1_IBM-SMS on hand. ALDs are explained by the SMS book, starting on page 12. The main impediment I had to understanding the ALDs was "what do those cryptic notations in the boxes mean?" That's explained starting on page 14."

Here is the info and index that John Dean made for us

IBM 1401 ALDs from the Australian Computer Museum Society

Scanned May 2006. ACMS has no copyright claim on this material. Secretary John Deane, email jdeane@ihug.com.au

1401 40-28588 2151/788 Logic - Diagrams 1/1 (30 X 43 cm, 156 pages, p. 31 poor)

Index for 1401 machines above serial 25000 Index for IFC 1-5 Clocking and storage 6-32 Data flow and controls 36-50 Arithmetic operation 56-60 Basic operations 66-69 Advanced programming 71-76 1406 expanded storage 81-120 Input/Output 126-133 Magnetic tape and I-O attachment controls 136-139 Overlap controls

1401 40-28588 2151/788 SMS - Cards 1 1/2 (30 X 43 cm, 111 pages, pp. 5,64,105 poor)

4 pages of index then circuit & physical layout card by card 1401 40-28588 2151/788 SMS - Cards 2 2/2 (30 X 43 cm, 160 pages, p.56 poor)

& continued

1401 40-28588 2151/788 SDI - Plugg.Charts + Power - supply 1/7 (30 X 43 cm, 98 pages)

1401 - SYSTEM INSTALLATION PROCEDURE (11 pages) Alphabetical logic listing ..., Circuit card location charts... 1401 40-28588 2151/788 21-32 2/7 (30 X 43 cm, 118 pages)

1403 or 1404 Summary Connector #1 (6 sheets) Logic drawings 31.01.1.2 to 32.46.11.2 1401 40-28588 2151/788 34-35 3/7 (30 X 43 cm, 92 pages)

Logic drawings from 34... to 35... 1401 40-28588 2151/788 36-41 4/7 (30 X 43 cm, 145 pages, p.130 poor)

Logic drawings from 36... to 41... 1401 40-28588 2151/788 42-44 5/7 (30 X 43 cm, 45 pages)

Tiedown list (2 pages) Logic drawings from 42... to 44... 1401 40-28588 2151/788 46-99 6/7 (30 X 43 cm, 99 pages, p.55 poor)

Logic drawings from 46... to 99... 1401 40-28588 2151/788 TAU 7/7 (30 X 43 cm, 89 pages)

Reference Page Inputs from tape unit (6 pages) Logic drawings & waveforms

Included in the binder for 1/7 there was1401 38.11.11.1 to 38.11.75.1 etc (21 x 30 cm, 30 pages)

John Dean also sent the following pictures of their storage area. This is a chart of 1401 gate functions and ALD numbers We had originally planned on printing the ALDs, and the current format is ideal for that :-))

On-line posting/viewing the Australian ALDs is a little more "interesting".

I did an initial experiment breaking a 50 megabyte file into 8 parts for easier access by folks with dial-up lines. Those were not small enough - OK - enough - life is tough - find a place with a fast access and burn CDROMs Or, I suppose I could send out a few if requested - So, here are the multi-page .tif files as converted to a more accessable .pdf format -

(Text from John Dean, above. )

- 1401 DPS Supplement S23-5013.pdf - 9 megabytes
- 1401 TAU 223-6867-2.pdf - 17 megabytes
- 1_1 Logic Diagrams 1401_40-28588 2151_788.pdf - 34 megabytes

1401 40-28588 2151/788 Logic - Diagrams 1/1 (30 X 43 cm, 156 pages, p. 31 poor)- Index for 1401 machines above serial 25000

Index for IFC

1-5 Clocking and storage

6-32 Data flow and controls

36-50 Arithmetic operation

56-60 Basic operations66-69 Advanced programming

71-76 1406 expanded storage

81-120 Input/Output

126-133 Magnetic tape and I-O attachment controls

136-139 Overlap controls- 1_7 SDI-Plugg. Charts + Power Supply 1401 40-28588 2151_788.pdf - 29 megabytes

1401 40-28588 2151/788 SDI - Plugg.Charts + Power - supply 1/7 (30 X 43 cm, 98 pages)- 1401 - SYSTEM INSTALLATION PROCEDURE (11 pages)
- Alphabetical logic listing ..., Circuit card location charts...
- 2_7 1401 40-28588 2151_788 21-32.pdf - 22 megabytes

1401 40-28588 2151/788 21-32 2/7 (30 X 43 cm, 118 pages)- 1403 or 1404 Summary Connector #1 (6 sheets)
- Logic drawings 31.01.1.2 to 32.46.11.2
- 3_7 1401 40-28588 2151_788 34-35.pdf - 18 megabytes

1401 40-28588 2151/788 34-35 3/7 (30 X 43 cm, 92 pages)- Logic drawings from 34... to 35...
- 4_7 1401 40-28588 2151_788 36-41.pdf - 37 megabytes

1401 40-28588 2151/788 36-41 4/7 (30 X 43 cm, 145 pages, p.130 poor)- Logic drawings from 36... to 41...
- 5_7 1401 40-28588 2151_788 42-44.pdf - 12 megabytes

1401 40-28588 2151/788 42-44 5/7 (30 X 43 cm, 45 pages)- Tiedown list (2 pages)
- Logic drawings from 42... to 44...
- 6_7 1401 40-28588 2151_788 46-99.pdf - 26 megabytes

1401 40-28588 2151/788 46-99 6/7 (30 X 43 cm, 99 pages, p.55 poor)- Logic drawings from 46... to 99...
- 7_7 1401 40-28588 2151_788 TAU.pdf - 23 megabytes

1401 40-28588 2151/788 TAU 7/7 (30 X 43 cm, 89 pages)- Reference Page Inputs from tape unit (6 pages)
- Logic drawings & waveforms
- 1401_38_11_XX_Xetc.pdf - 8.8 megabytes
- 1_2 SMS-Cards 1 1401_40-28588 2151_788.pdf - 48 megabytes

1401 40-28588 2151/788 SMS - Cards 1 1/2 (30 X 43 cm, 111 pages, pp. 5,64,105 poor)- 4 pages of index then circuit & physical layout card by card
- 2_2 SMS-Cards 2 1401 40-28588 2151_788.pdf - 59 megabytes

1401 40-28588 2151/788 SMS - Cards 2 2/2 (30 X 43 cm, 160 pages, p.56 poor)- & continued

Updated through June 10, 2015

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