Keyboards Ain't What They Were

February 4th 2001

IBM XT Keyboard

IBM XT 88 key keyboard with distinctive 'shouldered' keys

Recently, I've gotten interested again in ergonomics and keyboards, driven mainly by a couple of things:
  1. a growing discomfort with my existing "ergonomic" Microsoft Natural Keyboard, and
  2. the aquisition of an original IBM PC/XT, with it's keyboard.
If you haven't been around computers long enough to have used one of these behemoths, here's the rundown: The XT itself is pretty much useless now, although it's interesting to look inside - the thing is full of electronics - eight 8-bit slots nearly all occupied with 'long' cards (that is, front-to-back cards - you don't see them often anymore). It has a 400W PSU, and separate offboard cards for: serial port, parallel port, CGA video, hard disk, and floppy disk - nothing is integrated. I got mine with two IBM monitors: the rather average CGA Color Display and the really dinky lightweight monochrome one - unfortunately I don't have an MDA or Hercules card to run that screen. The keyboard weighs a LOT (around 5.5 lbs), has a really clicky, heavy action - a lot like an IBM Selectric electric typewriter, and feels lovely.

I got the XT partly to augment my growing collection of 80's junk, and partly after seeing numerous mentions in discussions of keyboards on places like Slashdot where people swear by these old IBM 'boards. At college I spent a lot fo time typing on IBM PC/ATs and PS/2s which I did remember as having pretty good keyboards.

One reason given for people's problems with modern light-touch keyboards is that your hands are constantly in tension over the keys so that you don't accidentally press them. You can very safely rest you hands on the keys with an older keyboard.

IBM XT Keyboard

A nice, old-style IBM badge, too!

The other benefit of these older keyboards is that they are built like tanks, as is the rest of the XT - it's very obvious that IBM took some serious hardware engineers and told them to 'make it cheaper' - they didn't really dig cheap the way that modern manufacturers do. If you open up the XT keyboard, you'll find that it is backed inside with a 3 or 4 mm sheet of steel, followed by another thinner sheet which holds the keyswitches.

It's the keyswitches that make the difference to the action of the keyboard. If you open up a modern keyboard like my Acer, you will find: a couple of sheets of plastic with printed tracks, the keys clipped into the top half of the frame, and about 100 little plastic domes. The domes provide all the action for the keyboard - they have a little conductive blob in the bowl of the dome, and the dome deforms when you press the key. They're really cheap to make. They also, in my opinion, suck. The MS keyboard is roughly the same inside, except that the keys are mounted in 4 separate panels to allow for the shape.

To compare from a weight point of view, my standard Acer $10 keyboard weighs 900 g and my Sun Type 4 (which is fairly substantial itself) weighs 1370 g. The IBM weighs 12100g!

However, the twist in the tale of the XT is two-fold:

  1. the PC and PC/XT use the older 88-key layout rather than the 102-key 'enchanced' AT layout we know and love these days. This means you lose F11 & F12, the other f-keys are down the left-hand side instead of across the top and you don't have separate editing & cursor keys - you need to use numlock if you like to use the numpad in Excel. I knew about that, but didn't think I used the numpad as much as I apparently do.
  2. the less obvious twist is that they don't work on modern PCs. It appears the PC and XT didn't use the same connection as the AT and later. It's still a 5-pin DIN, but it just locks up on newer machines. This is something of a show-stopper.

These guys make and sell keyboards under license from Lexmark (the part of IBM that makes their printers and keyboards). For $50, you can have the snappily-named 42H1292 - a 102-key old-feel keyboard with PS/2 connector. It's not quite the same heavy-duty keyboard as my 1983-vintage one, but it's got the same sort of feel. The key phrase to look for is "buckling spring" - a description of the keyswitch mechanism.

July 8th 2001. I got a mail today from Shaun, who recommended the IBM Model M keyboard - apparently an AT layout real buckling spring keyboard. It was also good to know that someone else has a set of pages making a fuss about keyboards :)

Update for 2009: Here's a very comprehensive guide to the various mechanisms and printing methods and so on for keyboards!

Copyright 1994-2005, by Howard Jones.