Scanning question (Is destruction of old tech docs a moral crime?)

Guy Dunphy guykd at
Mon Jul 22 22:28:02 CDT 2019

At 07:16 PM 22/07/2019 +0200, Mattis Lind wrote:
>> BTW. I have three IBM 026 card punch machines as a future restoration project. But can I find
>> a service manual? No. None online, only one for the later 028. And even if there was a PDF

>Have you seen these:

Last time I looked, in Sept 2018 I had previously found:
Bitsavers has a user manual:
And a field manual:

But no schematics still.

Your first URL is 404'd, though I already had that doc. Seems there's been a tree structure re-org.
Now there's these:

Looks like a good complete set, for mechanicals. Still no overall schematic. Maybe it didn't exist?

Gosh it's a scary-complicated machine. I'm not looking forward to finding the gotchas, like obscure
parts buried deep in the guts that have perished rubber bits, complex precision surface-hardened things
that are just plain worn out and unobtainium, etc.

>> I expect it would be the usual terrible quality.

Pleasant surprise! The image quality of all those PDFs is pretty good. But all still a mix of 2-tone
and JPG encoding, with all their various artifacts.
Fortunately at high enough res to preserve all information. High enough even to (mostly) preserve
the ink screening dots in images.

I'd still like to find original paper copies, both as a historical set with the machines, and to
scan-encode-wrap 'my way' for better looking digital versions.

>> Ditto for a service/schematics manual for the Documation TM200 punch card reader. No copy can be found.

>Do you expect the TM200 to be substantially different from the M200? My guess is that they are quite similar.
> Gone down the route of reverese engineering the differences?

The TM200 has extra circuitry (more cards, wiring) than the M200, since it also reads optical mark-sense cards.
Which means if ultimately I'm forced to reverse engineer the diferences, it's going to be a lot of work.
There's no rush and plenty of other projects. I'd rather just wait more to see if a correct manual turns up.
Not to mention that I'd like to find that manual in order to scan it.


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