Keyboard QnA

I have gathered a list of questions people may have about IBM and family keyboards and have attempted to answer them. These range from questions beginners in the keyboard hobby may have, what prospective IBM and family keyboard buyers may want to know, and even some research-style technical questions. Some of these may have subjective answers, so please don't be surprised if other people or websites answer them differently.

Can I use Model Ms for gaming?
Absolutely, but with some considerations in mind. Model Ms indeed have the reputation of being more of a typing instrument rather than a gaming peripheral, but there is nothing physically stopping you from gaming with them and many people game with them without fault. However, depending on your preferences and desired key combinations, there are some things to consider. Firstly, Model Ms are limited to 2KRO. Whilst this doesn't mean the keyboard is limited to just two-key combinations since in practice 3 or 4 simultaneous keypresses are commonplace, it does mean there are some instances of a hard two-key limit somewhere in the keyboard's matrix. Secondly, buckling spring switches are known to have relatively high hysteresis (when the switch's release point is above the actuation point). This may present a problem with rapid key presses. In conclusion, Model Ms can be used for gaming. However, they are not suited for games that require large key combinations and rapid key pressing.
How much should I be concerned about failing plastic rivets on a Model M?
Model M keyboards in fact frequently exchange hands without fault, however, a not insignificant number of Model Ms are affected by dreaded plastic rivet failure. The most likely Model Ms to be suffering such catastrophic plastic rivet failure are ones that are so old that the plastic itself begins to degrade, those that come from industrial use, and those that come from areas of the world with inhospitable climates. In my opinion, it's fair to have a healthy dose of scepticism whilst shopping around - if possible ask for photos of the insides of a prospective Model M purchase, and if a seller outright refuses, walk away.
I want to use my vintage PS/2 keyboard with a modern PC - how?
Converters for PS/2 to USB keyboards are plentiful, but you will need to be vigilant in regards to the type you need. Both passive adapters and active converters exist, with passive adapters simply being a pin swap between the two types of connectors for more modern PS/2 keyboards that also support USB protocol internally. Your '80s Model M, for example, cannot do this, so what you need is an active converter. As a rule of thumb, active converters are specifically labelled as such, sometimes described as having a USB integrated controller (IC), feature a small box in the middle of the cable, and more often than not include both keyboard and mouse PS/2 ports together. Exceptions to this exist, however, so be sure to check out reviews and ask the manufacturer to clarify.
Was there any official distinction between the IBM 6580 Displaywriter System's beam spring and Model F keyboard variants?
Yes! The beam spring keyboard is known as Type A and the Model F keyboard is known as Type B. The February 1983 revision of the IBM Displaywriter System Product Support Manual describes these terms on Chapter 5 (Keyboard), specifically on page 64 of the bitsavers' PDF scan of this document. Figures showing the Type A and Type B assemblies are visible on page 63 (Figure 5-1) and page 64 (Figure 5-2) respectively.
What do the 'a with caret/chevron' and 'a/aaa with cross-out' keys on Model F104, F122 and early M122 keyboards do?
For the keyboards' original terminal layout, the 'a with caret/chevron' key functions as an insert key and 'a/aaa with cross-out' functions as a delete key. Evidence for this can be found by examining the Model F-based IBM 3270 PC Keyboard Element (such as P/N 6110344) - specifically, by comparing the physical layout (credit to John Elliott) with a known functional layout diagram (credit to John J. G. Savard).
What screwdriver do I use to open up my Model M with?
For mainstream buckling spring and Quiet Touch rubber dome Model Ms, you are looking for a 5.5mm (7/32") nut driver. They can be bought for just under £5 off eBay as of 2020. They are typically sold as being for Vruzend battery kits or for bicycles.
What's the difference between a passive adapter and an active converter?
The key is in the noun that passive or active is paired with. Whilst many may use the words adapter and converter interchangeably, there is a technical difference and the best way to look at it is as follows: an adapter adapts between two or more given physical interfaces, and a converter converts a between two or more given signals and possibly adapts the physical interface at the same time. With this in mind, a passive adapter simply changes one physical interface to another without modifying the electrical signals - for example, an AT to PS/2 adapter would be considered passive since both use the same underlying protocol and only the physical connectors are different. By contrast, an active converter processes the data running between the keyboard and host computer with an integrated circuit for the purpose of transforming one protocol into another - for example, a Soarer's Converter would be considered active since it converts the Set 1/XT, Set 2/AT or Set 3/terminal scancodes of the keyboard into USB HID scancodes.
Where can I find classic smooth TrackPoint nub caps for my M4-1, M13 or ThinkPad?
Due to Lenovo's use of lower-profile soft rim and soft dome TrackPoint nub caps, finding high-quality classic-style caps is getting harder. However, Unicomp still sources and sells classic 'eraser head' style TrackPoint nub caps. They are P/N 49G2224 and cost $5 for 3 caps, and they should be compatible with Models M4-1, M6, M6-1 and M13 keyboards, as well Unicomp EnduraPro keyboards and most IBM or Lenovo ThinkPads and TrackPoint keyboards designed and produced before the adoption of lower-profile caps.
Which are better - Model Fs or Model Ms?
The answer now has its own page as part of the buyer's guide (Which are better - Model Fs or Model Ms?).