Model Ms internals swap

[Idiot_Hacker]

I fear there are some ebay sellers that are using the casing from older Model Ms and putting parts from newer Model Ms into them. That way they can sell the keyboards for higher prices because the casing has an older date.  Please beware gentlemen(and ladies if there are any on this forum)!

[Idiot_Hacker]

Well I know brian does "constructs"..so two broken keyboards can become one. Could be a broken case, more typically switches and keycaps.

I fear the average consumer will not know this and be duped into thinking that they got a steal on an older model M.  The fact of the matter is the newer model Ms definitely feel different from the older model Ms.  While the older ones have that much more lower pitch and less vibration, the newer model Ms have a much higher pitch and I can feel the keyboard vibrate a bit with every keystroke.  This is due to the fact that older model Ms have a much thicker metal plate then later model Ms.  Also, let's make sure!   I am talking about all IBM built model Ms not Lexmark, Unicomp, Maxi Switch, etc.  I hope everyone gets a chance to read this post and take a took that there model Ms and if it is 88 and older to look for this.

One of the reasons why I rather get a fifthly keyboard is that I know all the parts are original to the keyboard.  If I get some free time, I will post a photo essay on the revisions IBM did to the model M.

Thanks for reading!

[nowsharing]

Interesting observation. Are there any places on the internals where the original part # or year is listed? I actually wanted to know this anyways because of label-less space-saver that I have.

I will post a photo essay on the revisions IBM did to the model M.

That sounds very interesting, I'm looking forward to it.

On a side note, are the cases all the same relative size? For example, would the 1401 internals fit the older 0131 cases? I have an old terminal 1390123 with the square logo that I would love to have working, even if it's a farce.

[Idiot_Hacker]

Interesting observation. Are there any places on the internals where the original part # or year is listed? I actually wanted to know this anyways because of label-less space-saver that I have.


That sounds very interesting, I'm looking forward to it.

On a side note, are the cases all the same relative size? For example, would the 1401 internals fit the older 0131 cases? I have an old terminal 1390123 with the square logo that I would love to have working, even if it's a farce.

The casing of all the model Ms are the same in terms of fitting the various internals revisions that IBM made.  However, the tooling of the plastic is different and some are tooled and finished better then others.  One of the most important things to look for is a faint blacking number stamping on both the insides of the top and bottom part of the housing.  Unfortunately it seems they used non-permanent ink and any touching or washing of the area with the stamp will instantly wash it off.  On a previous post, I recommend to anyone with a not made for PC model M to just change the circuit board with one from a PC and it should work.  the 123 that you have has no lights but in case there is a version out there that has lights, there are two connectors IBM used to connect the LEDs to the circuit board.  Older model Ms like the 131 used wires with connectors at the end while I believe all 141s uses a plastic ribbon cable.  An obvious cost savings measure.  

Again, I can't state it more but all 88 and older model Ms are really the best because of the thicker metal plate, metal support bars for numpad + and numpad enter buttons.  Plus, on the older model Ms, the stands for supporting the space bar metal bar support are separate pieces of plastic attached to the plastic board.  On the newer models, it is a integrated stand which creates a hole onto the membrane which in theory would allow liquids and dirt to touch the membrane which to me is a no no.  The older model Ms don't have this hole which I believe was needed for IBM to integrated those plastic stands.  The thicker metal plate allows to less vibration and a lower thump and click pitch then the thinner metal plate.  I also believe the plastic used for the keyboard plate on older models are a different grade of plastic.  However the off-white plastic housing is the same throughout until Lexmark took over.  With Lexmark, there are huge variations with the plastic housing but I will get into that another time.

[nowsharing]

I recommend to anyone with a not made for PC model M to just change the circuit board with one from a PC and it should work.

That sounds too good to be true; you're saying I can just swap the circuit board from a newer M into the old terminal board and it will function as an AT or PS2 board?! :pray:

[Idiot_Hacker]

That sounds too good to be true; you're saying I can just swap the circuit board from a newer M into the old terminal board and it will function as an AT or PS2 board?! :pray:

yes sir,

IBM built this to be interchangable and modular.  I believe the european models are a bit different because of the orientation of the enter key and the 102 key layout but yes,  all that is need to change is the circuit board.

[nowsharing]

yes sir,

IBM built this to be interchangable and modular. I believe the european models are a bit different because of the orientation of the enter key and the 102 key layout but yes, all that is need to change is the circuit board.

That really makes my day. My 0123 is like new and I have several grungy Ms to choose from for the board, thanks for the info! How do you know so much about the M?

All nice but swapping the entire inside doesn't make sense.

That's a good point--it would seem like a rare example where the internals on a nice looking older board broke in such a way as to require a full transplant.

[Idiot_Hacker]

All nice but swapping the entire inside doesn't make sense. That would imply the inside of a valuable keyboard to be broken and the outside intact. How often does that happen? In any case, I've never seen it.

Sure it does, for someone looking for an old model M, older dates makes the keyboard more valuable.  The outside casing is very durable.  Someone could have spilled something onto the the internals or someone messed up some of the springs.  Taking an "inferior" inwards of a newer model M and putting in into an older case would make the broken older model M into something that is desirable and worth more then a model m with a newer date

[Idiot_Hacker]

I still don't think this is common. First, the seller needs a big supply. You got the clueless ones, like recylcedgoods.com, and they are not even capable. You got the capable ones, like brian, but he wouldn't be so stupid to swindle his customers and endanger his reputation and operation for a few tenners. He might complete missing keycaps from an equal board and such. And then presume for a moment there is a category which does what you say. Considering the time one has to put into it and the possible gain, this is a real bad way to become rich quick. Again a career at McDonalds seems a quicker path. Anyway, if you fear this is happening there must be a reason for it. May I ask what happened?

I don't want to mention it yet because I am in the process of rectify the matter.  I do implore fellow lovers of model Ms that I believe that the only true model Ms are 88 and older.  I will post a photo essay as soon as time allows.  I would also like owners of multiple model Ms to compare 88 and older with newer IBM built model Ms and let us know that you feel the differences are.

Thanks everyone

[microsoft windows]

Overall, I'd say that no matter how old the Model M is, it is still a very high-quality product. I have one manufactured in 1994 by Lexmark with a trackball (the M5-2 model). It was pretty grungy when I first found it but I washed it off and took it apart to see what was inside. A 1993 date was stamped on the outer casing and I found a slip of paper inside saying the date and time the unit was asswmbled. It said sometime in July 1994.

Using a scale I weighed the old clunker and it weighed a whopping 7 pounds. It still works well after enduring nearly 15 years of very hard use in a school environment. It does have a few scratches and dings here and there and a few key-caps missing, but I use it every day on my main computer. The keys never stick even though I never cleaned out the black panel holding all the keyswitches.

I've heard many people claiming those keyboards with the drainage holes are lower-quality. However, they are still VERY high quality products which can easily withstand decades of hard use.

While I personally do not see much wrong with change the internal components of the keyboards, people should at least say so if they did it. That's the good and honest thing to do just in case if there is a collector desiring that specific model.

[Shawn Stanford]

I don't want to mention it yet because I am in the process of rectify the matter.  I do implore fellow lovers of model Ms that I believe that the only true model Ms are 88 and older.  I will post a photo essay as soon as time allows.  I would also like owners of multiple model Ms to compare 88 and older with newer IBM built model Ms and let us know that you feel the differences are. Thanks everyone

I'm not getting it... A keyboard is a tool. I have a 1993 Model M that was part of a PS/2 I used at work for many years. Eventually, they took the PS/2 away in favor of an upgrade, but I hung on to the keyboard. I'm a programmer and I don't even want to think about how many keystrokes this thing has endured; many of the alphabetic keys are literally worn smooth through use. However, it soldiers on and it has given me years of yeoman service. To say this isn't a Model M is, frankly, crazy talk. If it walks like a duck and quacks like a duck, it's a duck.

As far as the desirability of older model Ms versus newer model Ms: pish. From where I sit, all model Ms are the same except for those that are/were attached to IBM 327x terminals.

[MANISH7]

Shawn - you are being PRACTICAL. From that sensible point of view, you are absolutely correct. Impractical people like me appreciate the extra, subtle care put into the older models. It's ridiculous keyboard snobbery, I know. I'm on the lookout for a NIB 1988 M just to collect it.

Idiot Hacker: if you ever get access to a scale, I'd ask you to weigh a 1989+ IBM made 1391401 vs your 1988 keyboard. I doubt there will be a weight difference. Nevertheless, the support wires in the number pad are a clear sign of the extra care placed in the keyboards.

[Hak Foo]

The casing of all the model Ms are the same in terms of fitting the various internals revisions that IBM made.  

The later Ms (and descendants) with the fixed cable have a different back... they have the hole for the cable to stick out of, and the space for the socket is plugged.

connectors at the end while I believe all 141s uses a plastic ribbon cable.  An obvious cost savings measure.  

The 20 May 1987 401 I've been fiddling with has seperate wires to the LEDs, but films to the matrix.

 I also believe the plastic used for the keyboard plate on older models are a different grade of plastic.  However the off-white plastic housing is the same throughout until Lexmark took over.  With Lexmark, there are huge variations with the plastic housing but I will get into that another time.

I'm wondering if there's a significance between the white plastic and the black.  I've got a '90 with a white tray, and the others-- both older and newer- are black.

[nowsharing]

You guys should get together and put together a Wiki entry. This info seems to be spread all over the place in random postings and might be useful to new collectors.

I was thinking this too, and as a bonus, people could update it with new findings. It's the difference between an article and a legacy!

[Shawn Stanford]

Shawn - you are being PRACTICAL. From that sensible point of view, you are absolutely correct. Impractical people like me appreciate the extra, subtle care put into the older models. It's ridiculous keyboard snobbery, I know. I'm on the lookout for a NIB 1988 M just to collect it.

True, I pretty much always approach things from a practical 'what can it do for me' point of view. For instance: I'm also interested in mechanical watches, especially Seikos, and vintage military watches. I own several Seikos - most customized - and a couple of vintage military watches. The collector communities for these items are sometimes crazy, with individuals boasting hordes comprized of dozens or hundreds of watches, most of which never see the light of day or even live under lock and key in safes.

Craziness! :smile:

[sandy55]

re;swapping control pcb

By cost saving reason,  42H1292 ( with a fixed cable from right upper end ) uses different way of signal connection from older Ms.

So it's better to use a control PCB from 1391401 or older M with a detachable cable.

Some pictures of control PCB are available in my page
42H1292 is available at this page
Here is another page for M's PCB maintained by L.F.O.

I do agree with Idiot_Hacker that a 1390123 can be used as a ps2 or AT keyboard with a control PCB from 1390401 or other Ms with a detachable cable.  One thing you have to do is cutting out a square hole for a connector.
BTW, 123 is not an XT keyboard.

[Idiot_Hacker]

The later Ms (and descendants) with the fixed cable have a different back... they have the hole for the cable to stick out of, and the space for the socket is plugged.



The 20 May 1987 401 I've been fiddling with has seperate wires to the LEDs, but films to the matrix.



I'm wondering if there's a significance between the white plastic and the black.  I've got a '90 with a white tray, and the others-- both older and newer- are black.

Yes, from your post, it does appear that early 401s have the same internal build quality as the 301s.  I hope to the heavens I have some spare time in the near feature to open the model Ms that I have and know are true originals and do a picture by picture comparison of the variations the model Ms went through.  I however will only focus on IBM made model Ms for my first photo essay.