PowerBook Duo 230 keyboard

[za9ra22]

I recently acquired a Duo 230 in generally good, working condition, but it really has a pretty poor keyboard which feels rather spongy and misses random keystrokes.

I know the keys have a central plastic plunger which slides inside rubber, which after all these years is probably a bit resistive. Can this be lubricated, and if so, what would be best to use?

I also think it best to use the laptop without the battery in it, since it's dead anyway, but would like to keep the battery slot closed up. Can the sliding cover on the battery itself be removed from the battery and used? The plastic cover is fragile, so I don't want to force it.

 

[MacTech68]

The Duo keyboards were very poorly made, and often would suffer from 'unresponsive' keys.

The main problem appears to be the two layers of thin plastic film, which have silver tracks printed/painted on them. The silver tracks seem to oxidize and are so thin that they eventually develop breaks in the tracks.

Whenever these came in for service, replacement of the keyboard was the only option (at the time).

However, depending on how desperate you are, if you can get the three sheets apart (I can't recall if disassembly is easy or not), you MAY be able to use a "rear demister" repair pen (for cars) to fix the tracks - note this idea is untried & un-tested. Cleaning them doesn't help and mild solvents will completely obliterate the tracks - tread carefully.

Tracks near to the connector that plugs into the logic board would be extremely difficult to re-paint due to how narrow the tracks and their spacing is.

As for the sponginess, I recall them being this way. IIRC there is a single rubber mat with the key 'bumps' which push the key back up when released (similar to modern keyboards). The two plastic sheets with the tracks are separated by a single plastic sheet with a hole for each key to allow the upper sheet's pads to electrically contact the lower sheet's pads via circular carbon pads on the underside of the rubber sheet.

Use the "Keyboard" desk accessory in the 'Apple Menu' to test the keys if necessary.


EDIT - to add a look at some of what you might be in for:

Apple PowerBook Duo 230 – Broken Caps Lock LED « modelrail.otenko

modelrail.otenko.com

EDIT 2 - from the same blog, a report of success - take care.

Apple PowerBook Duo 230 « modelrail.otenko

modelrail.otenko.com

EDIT 3 - a few edits now that my memory is refreshed.

 

[za9ra22]

Oh....

Well, every key works, just they are all a bit spongy. That said, it is pretty uniform across all the keys, so perhaps it'll just take some getting used to.

The missing keystrokes seem to be when a key is not pressed dead-center, because if on one side or the other it will generally not register. However, I can live with that. It seems definitely to be key action rather than something in the structure of the keyboard, because when it's on my desk and I'm typing on it normally, it works rather better. When it's on my lap, not so much.

I think I'll probably leave well alone - I'd rather have a Duo with a bit of a finicky keyboard than one with no usable keyboard at all.

Thanks!

 

[za9ra22]

Just in case anyone who has a Duo with a generally working keyboard that just feels crappy to use is interested....

My 230 keyboard does work, except for the cap lock light which doesn't. But it does feel quite stiff and resistive and in the case of some keys, if they are not pressed in the middle of the keycap they sometimes don't register.

As an experiment, I gently pried off each of the keycaps - leveraging each with a flat-blade screwdriver blade on each side. Each key has a central stem which fits inside a plastic shaft. I applied a small amount of vaseline inside the shaft and reassembled the keycaps.

The result is like night and day. The action is much smoother and the keyboard works much more reliably. In fact it is even quite pleasant to use.

I would have used a more suitable lubricant, but didn't have one available. I was principally interested in whether a Duo could fulfill my needs as a highly portable writing platform, and this proves that it could.