return to main page

ALDs - from Australia

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

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 was
1401 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. )

Updated through June 18, 2006
return to main page