Jump to content

Some questions about the IBM model M keyboard

Drama Lama
Go to solution Solved by Drama Lama,

The price went up to 100€ which would be too much for me

 

but still thanks everyone

I found a pretty good deal on a 1990 IBM model M keyboard 

What are the differences to older and newer versions?

Does it matter that the one I want to buy was made in the UK?( I heard there are differences between Mexico and UK made keyboards)

is there anything else I should look for when buying a model M keyboard?

 

thanks

Hi

 

Spoiler
Spoiler
Spoiler
Spoiler
Spoiler
Spoiler
Spoiler
Spoiler
Spoiler
Spoiler
Spoiler
Spoiler
Spoiler
Spoiler
Spoiler
Spoiler
Spoiler
Spoiler
Spoiler
Spoiler
Spoiler
Spoiler
Spoiler
Spoiler
Spoiler
Spoiler
Spoiler

hi

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Link to comment
Share on other sites

Link to post
Share on other sites

3 hours ago, Drama Lama said:

What are the differences to older and newer versions?

The oldest Model Ms have a silver square badge, the middle(?) Ms have a grey oval badge and the newer Ms have a blue and grey oval badge.

The earlier Model Ms had thick cases and thick steel plates, which got thinner over time.

Cables also changed over time, but can't remember how they changed.

3 hours ago, Drama Lama said:

Does it matter that the one I want to buy was made in the UK?( I heard there are differences between Mexico and UK made keyboards)

Not really. As far as I'm aware there's not much difference between British, American and Mexican made Model Ms.

Link to comment
Share on other sites

Link to post
Share on other sites

TLDR with the differences: over time, IBM and later Lexmark applied some cost-saving measures to the design to keep them 'competitive' with the rising horde of rubber dome keyboards at the time (which can be generalised into four generations, of which Unicomp continues to make the the fourth). Whilst it's argued whether these actually affected typing feel (some notice a relative difference, some don't, but all good condition Model Ms will type well anyway), it does potentially have quality of life implications. Deskthority's article on the subject explains the difference quite well, but TLDR in Enhanced Keyboard (101/102 key Model M) terms:

  • The metal backplate got progressively thinner resulting in a reducation of weight
  • Metal wire key stabilisers were swapped with plastic rod ones
  • Later Ms added drainage holes and/or channels for liquid spillage
  • Modular SDL to AT or PS/2 cables were progressively discarded in favour of fixed cables
  • The final generation had a unique controller board design that resulted in a change of the lock-light LED alignment from bottom-left to top-middleish
  • Of course, the IBM logo badge changed

For the most part, I wouldn't worry about the factory. Whenever IBM introduced a change to the design, most of the factories (predominately IBM UK, IBM US Lexington later Lexmark after 1991, IBM US Rest Of until 1993-ish, and IBM Mexico) seemed to have synced up within a year. The only major difference to note is that IBM UK Model Ms have a ABS spacebar with a grounding wire underneath, due to stricter European law to combat against static electricity build-up caused by CRTs, and they only partially implemented the drainage system (added holes for liquid to escape, but didn't add channels to make it easy for that to happen). Neither affect the typing feel or overall build quality, but just note the ABS spacebar can yellow. If that bothers you, you can just order a PBT-made replacement from Unicomp or find a US/Mexico sourced PBT spacebar off eBay.

 

As to what to look for and look out for:

  • Rivets. All Enhanced Keyboard-style Model Ms have an internal assembly held together with many plastic rivets that can break over time. If too many are missing, you run the risk of it feeling less crisp to type on or outright failure that can only be fixed with doing a 'bolt-mod' yourself or sending it to Unicomp for refurbishment. Some might have differing opinions, but usually up to five missing *should* be alright provided the ones missing are spread out (if ~5 were missing in one spot, there's probably trouble!)
  • The 7-digit part number on the back. The part number can be used to reveal most of the specs of the keyboard, confirm it's genuine by comparing the keyboard with other known examples, and tell what system they were originally intended for and what their connection type might be if not visible/stated. As a rule of thumb for PC-compatibles, 139012x/139014x (without lights for locks) means it's XT auto-sense, 139013x means AT, 13914xx means PS/2 systems, 92G74xx/42H12xx means PS/2 or other mid-'90s systems, etc. They can also reveal if it's a rubber dome variant that you probably want to avoid (71G46xx). Anyway, you can use my website's database, r/ModelM's wiki (which is based on my website's data anyway, in slimmer form), or deskthority's wiki to find out the specs of a keyboard from it's part number (provided it's known, if not and you can't find out more from Google, just post the part number here and I can help you)
  • The connection, given terminal Model Ms exist. Usually, it's obvious since most 102-key terminal Ms have an RJ-45-like modular jack, but there's some (like 13863xx) out there with a DIN connector that looks like AT but has a different pin arrange (240-degree vs AT's 180-degree arrangement). If unsure, the part number can be used to find this out.

Hope this helps!

Shark lover, Software dev + research student, game dev, web dev, curator of IBMium keyboards and ThinkPads, r/ModelM mod.

My PC: Ryzen 9 5950X, MSI B450-A PRO MAX, 32GB (4x8) DDR4-3000, RTX 4080, Corsair 5000X, 500GB NVMe for boot & IDEs + 1x120GB SSD for repos + 1TB 7200RPM for games library, Corsair RM850e, Windows 11 Pro + Arch Linux.

Link to comment
Share on other sites

Link to post
Share on other sites

1 hour ago, SharktasticA said:

TLDR with the differences: over time, IBM and later Lexmark applied some cost-saving measures to the design to keep them 'competitive' with the rising horde of rubber dome keyboards at the time (which can be generalised into four generations, of which Unicomp continues to make the the fourth). Whilst it's argued whether these actually affected typing feel (some notice a relative difference, some don't, but all good condition Model Ms will type well anyway), it does potentially have quality of life implications. Deskthority's article on the subject explains the difference quite well, but TLDR in Enhanced Keyboard (101/102 key Model M) terms:

  • The metal backplate got progressively thinner resulting in a reducation of weight
  • Metal wire key stabilisers were swapped with plastic rod ones
  • Later Ms added drainage holes and/or channels for liquid spillage
  • Modular SDL to AT or PS/2 cables were progressively discarded in favour of fixed cables
  • The final generation had a unique controller board design that resulted in a change of the lock-light LED alignment from bottom-left to top-middleish
  • Of course, the IBM logo badge changed

For the most part, I wouldn't worry about the factory. Whenever IBM introduced a change to the design, most of the factories (predominately IBM UK, IBM US Lexington later Lexmark after 1991, IBM US Rest Of until 1993-ish, and IBM Mexico) seemed to have synced up within a year. The only major difference to note is that IBM UK Model Ms have a ABS spacebar with a grounding wire underneath, due to stricter European law to combat against static electricity build-up caused by CRTs, and they only partially implemented the drainage system (added holes for liquid to escape, but didn't add channels to make it easy for that to happen). Neither affect the typing feel or overall build quality, but just note the ABS spacebar can yellow. If that bothers you, you can just order a PBT-made replacement from Unicomp or find a US/Mexico sourced PBT spacebar off eBay.

 

As to what to look for and look out for:

  • Rivets. All Enhanced Keyboard-style Model Ms have an internal assembly held together with many plastic rivets that can break over time. If too many are missing, you run the risk of it feeling less crisp to type on or outright failure that can only be fixed with doing a 'bolt-mod' yourself or sending it to Unicomp for refurbishment. Some might have differing opinions, but usually up to five missing *should* be alright provided the ones missing are spread out (if ~5 were missing in one spot, there's probably trouble!)
  • The 7-digit part number on the back. The part number can be used to reveal most of the specs of the keyboard, confirm it's genuine by comparing the keyboard with other known examples, and tell what system they were originally intended for and what their connection type might be if not visible/stated. As a rule of thumb for PC-compatibles, 139012x/139014x (without lights for locks) means it's XT auto-sense, 139013x means AT, 13914xx means PS/2 systems, 92G74xx/42H12xx means PS/2 or other mid-'90s systems, etc. They can also reveal if it's a rubber dome variant that you probably want to avoid (71G46xx). Anyway, you can use my website's database, r/ModelM's wiki (which is based on my website's data anyway, in slimmer form), or deskthority's wiki to find out the specs of a keyboard from it's part number (provided it's known, if not and you can't find out more from Google, just post the part number here and I can help you)
  • The connection, given terminal Model Ms exist. Usually, it's obvious since most 102-key terminal Ms have an RJ-45-like modular jack, but there's some (like 13863xx) out there with a DIN connector that looks like AT but has a different pin arrange (240-degree vs AT's 180-degree arrangement). If unsure, the part number can be used to find this out.

Hope this helps!

big huge thanks  your website is awesome and relly helpful

is 30 € a good price for the model 1391403 ( German ISO ) ?

it looks used but from what i can see in the pictures it's in good shape

Hi

 

Spoiler
Spoiler
Spoiler
Spoiler
Spoiler
Spoiler
Spoiler
Spoiler
Spoiler
Spoiler
Spoiler
Spoiler
Spoiler
Spoiler
Spoiler
Spoiler
Spoiler
Spoiler
Spoiler
Spoiler
Spoiler
Spoiler
Spoiler
Spoiler
Spoiler
Spoiler
Spoiler

hi

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Link to comment
Share on other sites

Link to post
Share on other sites

23 hours ago, Drama Lama said:

big huge thanks  your website is awesome and relly helpful

is 30 € a good price for the model 1391403 ( German ISO ) ?

it looks used but from what i can see in the pictures it's in good shape

That's an excellent price! European eBay prices are usually very whack compared to North America, so I would usually expect prices north of 100€!

Shark lover, Software dev + research student, game dev, web dev, curator of IBMium keyboards and ThinkPads, r/ModelM mod.

My PC: Ryzen 9 5950X, MSI B450-A PRO MAX, 32GB (4x8) DDR4-3000, RTX 4080, Corsair 5000X, 500GB NVMe for boot & IDEs + 1x120GB SSD for repos + 1TB 7200RPM for games library, Corsair RM850e, Windows 11 Pro + Arch Linux.

Link to comment
Share on other sites

Link to post
Share on other sites

1 minute ago, SharktasticA said:

That's an excellent price! European eBay prices are usually very whack compared to North America, so I would usually expect prices north of 100€!

Thanks 

Hi

 

Spoiler
Spoiler
Spoiler
Spoiler
Spoiler
Spoiler
Spoiler
Spoiler
Spoiler
Spoiler
Spoiler
Spoiler
Spoiler
Spoiler
Spoiler
Spoiler
Spoiler
Spoiler
Spoiler
Spoiler
Spoiler
Spoiler
Spoiler
Spoiler
Spoiler
Spoiler
Spoiler

hi

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Link to comment
Share on other sites

Link to post
Share on other sites

The price went up to 100€ which would be too much for me

 

but still thanks everyone

Hi

 

Spoiler
Spoiler
Spoiler
Spoiler
Spoiler
Spoiler
Spoiler
Spoiler
Spoiler
Spoiler
Spoiler
Spoiler
Spoiler
Spoiler
Spoiler
Spoiler
Spoiler
Spoiler
Spoiler
Spoiler
Spoiler
Spoiler
Spoiler
Spoiler
Spoiler
Spoiler
Spoiler

hi

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Link to comment
Share on other sites

Link to post
Share on other sites

Just now, James Evens said:

Keep looking. The best I saw was 10€ and listed as old keyboard.

wondered whether the seller didn't know what he was selling or just assumed the price would go up fast

Hi

 

Spoiler
Spoiler
Spoiler
Spoiler
Spoiler
Spoiler
Spoiler
Spoiler
Spoiler
Spoiler
Spoiler
Spoiler
Spoiler
Spoiler
Spoiler
Spoiler
Spoiler
Spoiler
Spoiler
Spoiler
Spoiler
Spoiler
Spoiler
Spoiler
Spoiler
Spoiler
Spoiler

hi

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Link to comment
Share on other sites

Link to post
Share on other sites

Just now, James Evens said:

Ebay-kleinanzeigen

Ebay Kleinanzeigen is literally Wild West with no sherrif. ( there are reasons why " r/wasletztepreis " exists )

But i'll try

Hi

 

Spoiler
Spoiler
Spoiler
Spoiler
Spoiler
Spoiler
Spoiler
Spoiler
Spoiler
Spoiler
Spoiler
Spoiler
Spoiler
Spoiler
Spoiler
Spoiler
Spoiler
Spoiler
Spoiler
Spoiler
Spoiler
Spoiler
Spoiler
Spoiler
Spoiler
Spoiler
Spoiler

hi

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Link to comment
Share on other sites

Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now

×