What do "M" and "F" stand for?

[digital_matthew]

Hey everyone. I was just curious as to what the "M" and "F" represent for IBM keyboard model designations. (I'm too lazy to do the research, so I thought I'd just ask.) Thanks!

[depletedvespene]

I'm biting my tongue here...

[Engicoder]

It's simply the IBM designation for the technology used for the line of keyboards.

[fohat]

Fine and Mediocre

[Muirium]

Mother and her lover.

Hearsay has it that M is for Membrane, which makes sense. Perhaps to much sense to be true! F is less clear. Flipper? Surely not. But then again, it kinda wants to be so…

[andrewjoy]

Mediocre and Fucking Awesome

[TheInverseKey]

Meh and Fantastic

[Darkshado]

I recall reading Farad somewhere, which is the unit of capacitance; no idea how legitimate that claim was.

[kbdfr]

Perhaps they were named that for the same reason Chanel N° 5 got its name



(Best fragrance ever, by the way.)

[depletedvespene]

I recall reading Farad somewhere, which is the unit of capacitance; no idea how legitimate that claim was.

So close, oh, so close...

(don't I wish )

[andrewjoy]

If we are going serious , i am pretty sure M stands for membrane.

No idea what F stands for.... flipper ?

[flowerlandfilms]

It's important to understand the corporate culture of IBM back in the day (and to a lesser extent now).
IBM made a lot of stuff for a very long time, as such they ran through every number combo and started using letters a long time ago to differentiate product lines. Therefore It doesn't stand for anything other than being another iteration in a long line of tedious and blandly named things.

IBM was a place to go to work, and wear a tie and sing company songs and be VERY VERY SERIOUS.
It was not a place for daydreamers to fiddle-faddle about coming up with cool or interesting names.
Apple is named Apple partially as a direct rebuke to this mode of thinking.
If anyone at IBM was ever caught spending more than two seconds on a naming scheme for a product they would have been summarily fired or possibly shot (fun fact: IBM did make rifles for WW2).

I'm sure the guy who came up with "Selectric" had their entire family sent to a re-education camp where colours other than blue are punishable by death.

As for why letters in this case instead of numbers, it's possibly a continuation of the nomenclature for their Alphabetic Tabulators from the 30's, Models B and C.

[Chyros]

There was also a Model C1, etc. which were types of "F", and iirc there were F's that were called Model M as well. I'm really not sure the letter is related to the sensing method. Even if it was, as flowerandfilms mentioned, I doubt it actually abbreviates for anything meaningful.

[__red__]

Pims Cup

[SneakyRobb]

To quote dw

"Membrane buckling spring (often "Model M"), Capacitive buckling spring (sometimes "Model F")"

[Aer Fixus]

There was also a Model C1, etc. which were types of "F", and iirc there were F's that were called Model M as well. I'm really not sure the letter is related to the sensing method. Even if it was, as flowerandfilms mentioned, I doubt it actually abbreviates for anything meaningful.

To my knowledge, the only Model Fs clearly labeled as Ms were the ones refurbished by Lexmark in the 1990s. They got given new labels (and sometimes part numbers) that mislabeled them as Model M keyboards.

And according to the wiki, the IBM 3178 keyboards had the model name of the terminal C1-4. Those boards, the XT, AT, 4704 and a number of other boards did not have labels claiming what model they were. More simply, they just had stickers their part numbers or even nothing at all.

[SneakyRobb]

I asked the IBM Archives and the guy there Max who is cool referred me to a copy of the IBM SiteLine June 1982 magazine. It discusses how the Keyboard F Mechanisn Manufacturing is doing more with less versus previous keyboards, Specifically the IBM Model B keyboard mechanism and the Model E keyboard mechanism.

It would appear that Model F and Model M are sequential models of keyboard mechanism.

The article mentions that Model B keyboards have an absurd 9 moving parts, where Model F only has 3. I assume the cap, spring and flipper.

So it is actually pretty likely that "M" doesn't reference Membrane at all.

https://imgur.com/a/D9CN4lX

[Myoth]

The article mentions that Model B keyboards have an absurd 9 moving parts

that's actually probably beamspring

spring
o-ring
slider
stem
beamspring
capacitive plate
housing ?
keycaps ?
????

[digital_matthew]

I asked the IBM Archives and the guy there Max who is cool referred me to a copy of the IBM SiteLine June 1982 magazine. It discusses how the Keyboard F Mechanisn Manufacturing is doing more with less versus previous keyboards, Specifically the IBM Model B keyboard mechanism and the Model E keyboard mechanism.

It would appear that Model F and Model M are sequential models of keyboard mechanism.

The article mentions that Model B keyboards have an absurd 9 moving parts, where Model F only has 3. I assume the cap, spring and flipper.

So it is actually pretty likely that "M" doesn't reference Membrane at all.

https://imgur.com/a/D9CN4lX

Thanks for that awesome post! I wonder if Ellipse has seen this...

[Chyros]

I asked the IBM Archives and the guy there Max who is cool referred me to a copy of the IBM SiteLine June 1982 magazine. It discusses how the Keyboard F Mechanisn Manufacturing is doing more with less versus previous keyboards, Specifically the IBM Model B keyboard mechanism and the Model E keyboard mechanism.

It would appear that Model F and Model M are sequential models of keyboard mechanism.

The article mentions that Model B keyboards have an absurd 9 moving parts, where Model F only has 3. I assume the cap, spring and flipper.

So it is actually pretty likely that "M" doesn't reference Membrane at all.

https://imgur.com/a/D9CN4lX

This is simply excellent. You should press him for as much material on these as he can come up with, it is invaluable!

Beamsprings have nine parts if you count the keycap, but not all of them (such as the housing and O-ring) are moving. Still, I can't think of anything else IBM made keyboard-wise that was "popular" at the time.

[JP!]

That a great read. Now I wish I could travel back in time and tour the factory.

[digital_matthew]

I want that key testing job. Also I move that we start saying "Keyboard F" instead of "Model F".

[Ellipse]

Great work SneakyRobb! Thanks for sharing the article.

[fohat]

"If there were a Weight Watchers Club for keyboards, Keyboard F would get the annual award.
It weighs half as much as earlier keyboards and stands only 1-1/4” thick."

[Xubuntu56]

From IBM support: Differences between 3590 Model B , E, and H Tape Drives
http://www-01.ibm.com/support/docview.w ... s8N1019509
Guessing model designations with a single letter were not restricted to keyboards?

[matt3o]

this needs to be wikified!

[Howard81]

My 1986 IBM XT “enhanced” keyboard (Model M without the LED panel) states Model G in the inner sticker..

[fohat]

My 1986 IBM XT “enhanced” keyboard (Model M without the LED panel) states Model G in the inner sticker..

That would usually be a 1390120.

Could you please post a photo?

[Howard81]

My 1986 IBM XT “enhanced” keyboard (Model M without the LED panel) states Model G in the inner sticker..

That would usually be a 1390120.

Could you please post a photo?

It's marked 1389969 on the outer case with 1386719 (and 1386751) on the inner chassis. UK ISO layout, so it will have a different part number to the US models. I have three or four of them, all from 1986 or early 1987 and all came with very late IBM 5160/XT systems I collected over the years. I can confirm this as I have a brand new in box IBM 5160/XT with the 1389969 Enhanced keyboard All of them have the black cable with the AT DIN plug.

The three 5170/AT Enchanced keyboards I have (silver IBM logo with the lock-light LEDs) are 1391406 on the case sticker. I'll have to crack one open to see what the inner chassis plate state.

This particular one fell apart on me in the late '90s due to broken rivets - I've just carried out a screw mod on it, hence the information was fresh in my mind. Apologies for the bad photos - it's evening here and dark outside! The two XT Enhanced keyboards I have to hand are both rather yellowed.

IMG_0976.jpg (916.36 KiB) Viewed 9196 times

IMG_0960.jpg (885.7 KiB) Viewed 9196 times

[Chyros]

Apart from the Model G thing, an XT Model "M" in ISO is quite the thing.

NOICE.