WTB: IBM Model M 122 repair

[ConiKost]

Hi!
I've found an old IBM Model M 122 with 240-degree DIN-5 connector, which was completly striped off all keys.
After cleaning and putting a new spare key set on it, I was able to test it with an usb converter.

Pictures: https://imgur.com/a/e4Vvhwa

It seems, some keys are dead:

Alt (Left)
F10
Hash Key
Numblock 0
Numblock Enter
Numblock ,
Numblock -
Numblock *
Numblock / (Hangs)

I also asked Unicomp, but they don't do any repairs for IBM keyboards.
Interestingly, they claim, acording to the part number, this would be an Model F, but I don't think, that this is true?

Looking at it, I think, some bolts went loose/missing, which could be the cause?
If so, anyone able to do a bolt mod for me or have a look, it that could be repaired?

Many thanks!

[depletedvespene]

That keyboard is definitely an M122, not an F122.

How's the rivet (not bolts!) situation? It looks like too many are missing (which would be why the numpad mostly doesn't respond). Have you tested the membrane directly?

The plate itself seems to be fine, and the controller doesn't seem to be in bad shape, so I'm guessing a bolt mod would fix your problems (although, it must be said, this IS a major undertaking for someone without previous experience in this regard).

[Muirium]

Squinting at imgur on my phone (hosting pics here on DT is way better) it looks to be shiny metal back plate, like a Model F but with rivets like an M. Could be one of those strange in-betweeny early Model Ms that still had some F characteristics; which would excuse the confusion.

Bolt modding a 122 is a lot of work for a low value board! I did it myself once.

viewtopic.php?p=434981#p434981

[fohat]

That keyboard is definitely an M122, not an F122.

How's the rivet (not bolts!) situation? It looks like too many are missing (which would be why the numpad mostly doesn't respond). Have you tested the membrane directly?

I'm guessing a bolt mod would fix your problems

Like he said. That keyboard is missing most of its rivets on that side and ALL of them under the numpad.

I am amazed that it works at all. You definitely need to do a bolt-mod and that will almost surely take care of it.

[ConiKost]

That keyboard is definitely an M122, not an F122.

Thanks, I was also pretty sure, this can't be an F, since the F122 I've seen looked differently.

How's the rivet (not bolts!) situation? It looks like too many are missing (which would be why the numpad mostly doesn't respond). Have you tested the membrane directly?

I guess, I mixed it up and meant instead of bolts the rivets? How do I test the membrane directly?

The plate itself seems to be fine, and the controller doesn't seem to be in bad shape, so I'm guessing a bolt mod would fix your problems (although, it must be said, this IS a major undertaking for someone without previous experience in this regard).

That's why I am asking for help, since I have zero experience in doing such a mod.

I am amazed that it works at all. You definitely need to do a bolt-mod and that will almost surely take care of it.

Yeah, when I saw this, I also was suprised, that nearly all keys just work fine.

[depletedvespene]

How's the rivet (not bolts!) situation? It looks like too many are missing (which would be why the numpad mostly doesn't respond). Have you tested the membrane directly?

I guess, I mixed it up and meant instead of bolts the rivets? How do I test the membrane directly?

The easiest, dirtiest way: get the keycap AND the stem out of the key position to test. Get the cap of a BIC pen. Put the hook of the cap in the barrel. Press down a bit. Works whether there is a flipper or not.

[ConiKost]

How's the rivet (not bolts!) situation? It looks like too many are missing (which would be why the numpad mostly doesn't respond). Have you tested the membrane directly?

I guess, I mixed it up and meant instead of bolts the rivets? How do I test the membrane directly?

The easiest, dirtiest way: get the keycap AND the stem out of the key position to test. Get the cap of a BIC pen. Put the hook of the cap in the barrel. Press down a bit. Works whether there is a flipper or not.

Thanks, seems to do the job. All dead Keys respond and seems to work with that method.

[Muirium]

Well, here’s the work ahead of you:

viewtopic.php?f=7&t=9169