Replacing keys on an 800 keyboard- how many different types are there?

ianoid · January 21, 2017

I have an 800 missing both shifts and ctrl. I actually have two different types of key caps and neither helps me. One type of key has a post on the underside of the key cap the doesn't fit this keyboard (mech doesn't attach in the right place on the keys- wrong offset). The other has no post, just "+" shaped" attachments for the key mech. Am I missing a piece for the latter keys to get them attached to the mechs or is there a third keyboard type (or more?) that I'll need these parts from? Or is there an Atari 800 keyboard FAQ I'm missing? The key mechs I have work ok, I'm just trying to clean up the system.

And BTW I'd be happy to trade since I have a full set of key caps and mechs from a non-working system (but of course we'd want to verify I have the right type for you and likewise).

Edited January 21, 2017 by ianoid

a8isa1 · January 21, 2017

I have an 800 missing both shifts and ctrl. I actually have two different types of key caps and neither helps me. One type of key has a post on the underside of the key cap the doesn't fit this keyboard (mech doesn't attach in the right place on the keys- wrong offset). The other has no post, just "+" shaped" attachments for the key mech. Am I missing a piece for the latter keys to get them attached to the mechs or is there a third keyboard type (or more?) that I'll need these parts from? Or is there an Atari 800 keyboard FAQ I'm missing? The key mechs I have work ok, I'm just trying to clean up the system.

And BTW I'd be happy to trade since I have a full set of key caps and mechs from a non-working system (but of course we'd want to verify I have the right type for you and likewise).

I don't have an answer but I just have a word of warning in case anyone is thinking about looking under 800 keycaps just to see which type of mechanism is there.

The key switch associated with those rectangular plungers is a bit complex. When you pull a keycap sometimes the plunger comes out with it. That plunger is very awkward to put back in properly.

I'll do my best to describe the switch mechanism. Keep in mind the last time I saw one was around 1983.

Inside the rectangular post is a 'V' shaped wedge. This wedge opens two halves of the switch when the plunger is depressed. The switch resembles two dinner forks with 3 or 4 tines on each 'fork'. The forks are back to back. When the switch is in good order one can carefully insert the plunger and wedge will slide between the two forks. If the plunger is slightly off center or the forks are worn or damaged the wedge is not going to fit into it's proper place. Because the wedge is inside the plunger one can not see the top of the forks. If the wedge is not in the correct place the tines can be bent in such a way that the wedge not only won't divide the two forks now. It never will.

I had never seen the second type of keyswitch, the one associated with that '+' sign fitting. I guess I still haven't seen it.

Edited January 21, 2017 by a8isa1