Duo 210 keyboard misses keystrokes randomly

[netfreak]

I picked up a Duo 210 a little while back with a problem where random keystrokes will not register on the computer. I haven't pulled the thing apart yet but wondering if anyone has ideas for something specific I should be looking for.

 

[Byrd]

It’s the usual nature of a PowerBook Duo keyboard, sadly. One of the worst to come from Apple with spongy keys that fail to register keystrokes if you type at speeds faster than a toddler.

cleaning or “exercising” keys might help

 

[Trash80toHP_Mini]

There was (still is?) a Duo KBD repair howto. Hopefully it wasn't on the defunct mainlyneatstuff(?) web site. Sponginess is relative to KBD revision, but was something you learned to live with for the portability and flexibility of the system. When docked it didn't matter.

 

[Franklinstein]

The keyboards on those things were, by necessity, very thin membrane types with silicone key contacts/reflex nubs (I'm sure there's a proper term for them but that's basically what they are: nubs). The OEM (Honeywell, I think) did the best they could but portable keyboard technology in the early 90s was not something most people remember fondly. 

Anyway the contacts on the membranes tend to oxidize and thus lose their conductivity, causing keystrokes to be missed. Sometimes exercising helps but otherwise you'll need to tear down the keyboard (they're not too hard to disassemble) and clean the membrane contacts until they're conductive again without, of course, completely removing the conductive paint or whatever from the membrane sheets in the process. There are/were some decent guides out there.

 

[netfreak]

Yeah I'm hoping to get around to doing that sometime over the winter.

 

[Trash80toHP_Mini]

IIRC it's a rubber ring replacement kinda deal?

 

[douglasgb]

I just posted my solution in the 'Improving a PowerBook Duo keyboard' thread: