Telcon Ambassador IV / VCS-204 Portable Terminal

[btb]

I just acquired this dumb (but oddly attractive) terminal for a really good price. So far I have found zero information on it other than a couple ads and the specifications listed here, page 69: http://www.bitsavers.org/pdf/datapro/alphanumeric_terminals/Datapro_C25-010_198302.pdf

Pleasantly surprised at how beautiful the CRT was the first time I turned it on. Just displaying garbage, but looked great.
I opened it up to clean out some of the garbage and grime, screen is just dark now .

Are there any other owners of such a machine out there?

I'd really like to find some documentation... Main chips are 6800 and two 6821's. It also has a secondary board for the built-in printer, which has a 6802 and 6821 on it.

Also, it's missing the top half of the case. I'm hoping it could be an off-the-shelf case and I'll be able to find a replacement.

 

[btb]

Screen back to working again.


Big floppy PCB + cheap sockets = lots of loose chips


Opened up the keyboard and oh my it's a disaster

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[btb]

Having a hell of a time bringing this keyboard back from the dead. I think it's had a few too many hotel margaritas dumped in it back in the day, lots of traces are just completely gone. I've worked out the matrix itself and many I can fix with jumpers on the back side. Others though, will be hard to do without interfering with the key mechanism on the front.

This is pretty representative of what I'm dealing with:



Every key has (or had) a ground trace running between the two half "plates", as well as being mostly encircled by ground. I would assume this is specific to how capacitive keys are supposed to function - I'd love it if I could find some more in-depth info on the theory of how these work. Is it an absolute necessity to recreate all these ground lines? If I run a 30 gauge wire across the gap, the height of the wire will end up raising the key mechanism up by that amount, as well as causing the foam pad to hit the wire first and make less contact with the pcb itself. The next, more difficult options, are very thin strips of copper foil, and conductive ink.

Or I guess, making a whole new PCB. Has anyone ever recreated one of these capacitive keyboards?