Typical problems and solutions concerning the M20 keyboard

The M20 keyboard is made by 80 switch which make a quite rassuring "click", when activated. In the 1982 culture, there were keyboards in which a buzzer emitted a beep for each key typed; it was important to acknowledge the user, as often the response of a key was not so obvious.
It is clear that now a 1982 keyboard may have problems due to miscontacts and several key can be nonworking.

The M20 keyboard We suggest to open and clean the M20 keyboard, if you experience problems due to misworking keys. It is not a difficult work, but it requires a lot of patience. If you have a digital camera, you can take a picture of the keyboard before removing the keys. This will save a lot of time when you will have to reassemble it and you will have to insert the key at the correct place.

The M20 keyboard without the keys During the ages, a lot of dust and dirty accumulated under the keys. You can easily remove them by pulling gently. Keep them for a while in soap water to remove grease and dust.

The M20 keyboard without the keys Each key is composed in two parts: the upper part, in which the letter is written and the contacts support, which is hold in place by the metallic frame on the printed circuit board. You can separate the printed circuit board and the frame.

The M20 keyboard opened You can clean contacts with a bit of alcohol. Avoid gasoline or acetone, as they can melt plastic.

The M20 keyboard opened Reassembling the keys is more a matter of patience than skill (thanks to Carlo for the idea of the animation :-).