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Unreliable key — Apple Standard Keyboard M0116
Posted by: 68kAlex on 2014-08-31 11:45:31
I have recently acquired a model M0116 keyboard (the compact mechanical version from the late '80s). It's in great condition overall, and I've just spent a couple of hours cleaning all the plastics. 

However, one of the keys is unreliable and I find myself missing that letter from time to time when typing.

Anyone got any ideas? Will a blast of compressed air sort it out, or is the switch likely on the way out? I was under the impression the Salmon Alps switches were rated for tens of millions of actuations.

Posted by: Elfen on 2014-08-31 12:44:42
Spray some Contact Cleaner into the slide of the switch. Something inside the switch is contaminating it.

Also take apart the keyboard base and see if the solder joint of the switch is intact. Desolder the switch and put in some fresh solder if the joint looks bad

Posted by: 68kAlex on 2014-08-31 15:10:23
Thanks. Is WD-40 likely to work? I don't have any contact cleaner to hand.

Posted by: techknight on 2014-08-31 15:48:50
not usually, no. Need a can of deoxit or something of the like. The plating on the internal contacts begins to tarnish, and it causes nastiness like this. 

Posted by: Quadraman on 2014-09-03 11:35:30
Taking the keyboard apart will most likely reveal crumbs, dust, hair, and other contaminants that shouldn't be in there. Cleaning all the crap out of the keyboard will go a long way to fixing any issues you may have with keys working sporadically. Oxidized contacts are easier to clean once you have all the other crap out of the way. 

Posted by: 68kAlex on 2014-09-04 02:25:08
Already cleaned the crap out of this keyboard. It's squeaky clean.

Posted by: 68kAlex on 2014-09-15 02:45:09
An update:

I've used contact cleaner on the switch, checked the solder joints, and even dismantled the switch to inspect the contacts. It's still intermittently missing keystrokes. Troubling!

Posted by: noidentity on 2014-10-12 14:21:41
I had an Extended Keyboard II like this and I found some green corrosion in the switch itself. I tried cleaning the switch but ended up switching it with a good one from a junk keyboard of the same model.

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