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geekhack Projects => Making Stuff Together! => Topic started by: rudmata on Thu, 18 October 2018, 10:55:00

Title: Anyone know what connector this is?
Post by: rudmata on Thu, 18 October 2018, 10:55:00
Hello!

I'm new to this forum.

I just got this (looks like) old industrial mechanical keyboard and would like to mod it (case and USB connection) for my PC, but I have no idea where to start adapting this PCI-looking connector to USB.
Said connector is 7cm in lenght.

If it helps, the switches have huge springs on the outside and are branded "Key Tronic" on one side and "Spokane" on the other.
The abreviations on some keys are in French but the layout is qwerty not azerty.

Thanks in advance!

[attachimg=1]
[attachimg=2]
Title: Re: Anyone know what connector this is?
Post by: Findecanor on Thu, 18 October 2018, 13:05:00
First, welcome to Geekhack!

Just from the side angle pic, the switches look like Key Tronic "foam-and-foil" switches (https://deskthority.net/wiki/Key_Tronic_foam_and_foil), older type. They are capacitive.
There should be a circular foam pad at the bottom of each slider with a mylar sheet, and those foam pads tend to deteriorate over time. There should be replacement pads being available though, and some people have even made their own.
You should be able to unbolt the switch plate from the PCB and check. If you pull a keycap, the key's spring and slider should then fall out the bottom.

From the symbols on the keycaps, it looks like a kind of "ASCII keyboard". The ASCII character set was actually designed to map directly to a typewriter layout (that pre-dates ANSI) to make it easy to construct keyboards that produce ASCII character codes directly. ASCII keyboards were made as OEM products that would slot into all sorts of computing and telecommunications equipment. I believe it is likely that you should be able to read ASCII in parallel on the connector (but how is another matter...).
This layout matches 1963 ASCII and (you can see that it is 1963 ASCII because of the up-arrow ↑ instead of the ^ character in later revisions).

However, USB does not use anything resembling ASCII, only raw codes of which keys are pressed.
So, if you did connect to the keyboard, your receiving microcontroller would have to interpret ASCII sequences and then send fake presses to the host corresponding to what it thinks the actual presses might have been, and that could be tricky. You would also be unable to send separate Shift and Ctrl presses, or map a key to a modifier such as Alt or Windows/Command.
But there might be another way that would go around ASCII altogether: replace the control circuitry with one of of xwhatsit's controllers for capacitive boards.
There is a thread over on the Deskthority forum (https://deskthority.net/workshop-f7/westinghouse-w1642-keytronic-foam-foil-xwhatsit-model-f-conversion-t17294.html) about using one for a Key Tronic board.
Title: Re: Anyone know what connector this is?
Post by: OldIsNew on Thu, 18 October 2018, 16:20:32
Yea, those certainly look like vintage KeyTronic F&F. Very nice looking board BTW! I've converted I think 7 or 8 or those boards using the Xwhatsit Model F to USB board. There are typically 20+ small screws on the back of the PCB and when they are removed it separates the PCB from the front plate/key switches.

The last one I did was a Data General Dasher: https://deskthority.net/workshop-f7/data-general-dasher-and-xwhatsit-usb-t19922.html

I posted a basic description of the process I've used here: https://geekhack.org/index.php?topic=97618.0

Title: Re: Anyone know what connector this is?
Post by: Leslieann on Thu, 18 October 2018, 18:08:16
That is closer to an ISA connector than PCI.

Why find a connector, solder right to the tab, I would even be tempted to cut a couple traces and wire in a Teensy. You may be able to avoid cutting traces by just desoldering the first and last component on a key trace, in which case it could be easily put back to stock later. May not even need to do that much.

Yes purists, I know I'm a horrible monster.
Title: Re: Anyone know what connector this is?
Post by: 1swt2gs on Thu, 18 October 2018, 19:08:13
Anyone know the date of this keyboard or when it was produced? Love the keycaps on it
Title: Re: Anyone know what connector this is?
Post by: rudmata on Fri, 19 October 2018, 02:27:49
Found this under the gunk after cleaning it:

[attachimg=1]

Looking good...

[attachimg=2]
[attachimg=3]

P.S.: I have almost no knowledge about electronics work, but I have reverse-engineered old hardware before, so: Thanks for all the advice everyone!
Title: Re: Anyone know what connector this is?
Post by: rudmata on Fri, 19 October 2018, 02:31:24

There should be a circular foam pad at the bottom of each slider with a mylar sheet, and those foam pads tend to deteriorate over time.

Yup... Most of the plastic cylinders under the key-caps are fallen inwards and non-responsive to touch.
Title: Re: Anyone know what connector this is?
Post by: OldIsNew on Fri, 19 October 2018, 17:52:41
As I mentioned, KeyTronic foam and foil boards are not really difficult to convert (I'm typing on one now) - just a bit tedious. Stick with it - that board you have is awesome looking!