Xerox 6040 typewriter, proto-topre foam-and-foil capacitative?

[hjalfi]

I recently got hold of a Xerox 6040 Memorywriter typewriter/word processor. The keyboard is really interesting, very tactile but super smooth and not at all clicky. It seems to be the chunkiest rubberdome I've ever seen with discrete sliders on top, and massive triple-shot keycaps. The mechanism itself is capacitative (most of the foil pads fell off as soon as I opened it). Pictures attached.

Is this of any interest? I don't see anything about it on the deskthority wiki, or anywhere else online, for that matter.

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[tactica]

viewtopic.php?t=24994

As Anakey commented in that thread it would seem that several kinds of those switches were used back in the day sharing a common mount.

You might look for markings on the PCB to try and identify the manufacturer. Information about typewriters on the wiki is rather scarce, that's just one of many things that need to be addressed.

[zrrion]

The switches on this look way different than my 6016, they look closer to the switches in my brother module, but using a different mount. Very cool to see this sort of discrete switch pop up in something else

[rsbseb]

I have a keyboard with these switches in my collection somewhere. I cant remember the make or application. I will try and see if I can track it down this weekend in storage. I don't think it's branded Xerox I think I would have remembered that.

[rsbseb]

Was unable to locate mine, would love to know more about this switch and what can be done to service and restore them.

[hjalfi]

The keyboard controller PCB doesn't have any branding, but is labelled KB-82 B48U082-4 JCI N1S. It's powered by a Fujitsu 8051 microcontroller in one of those long DIP packages with a groove down the side which makes me think it's a custom device. There is a parallel connector to the typewriter's application board. Interesting features include _two_ auxiliary connectors for the extra buttons around the keyboard proper --- one of them had an empty IDC plug in it. Not a jumper, a normal plug with no cable.

The main base plate is labelled "Brother F8042352 model 556-510-01 Part no. 110K01160 REV A". This makes sense, given that the Brother word processors I have also use the same proto-topre rubberdome mechanism, although not as nice as the Xerox.

Incidentally, if anyone wants it and is willing to pick up from Zurich, they're welcome to it. Otherwise I'm going to have to strip the machine down for useful parts and the rest will go to ewaste. It all works, except the keyboard.