Well,- I´m searchin´ ...
Original is Marquardt Switch 6401 which seems to be a discontinued part.
I measured my original switches and what eventually comes close most or will fit is the actual Marquardt Series 6425 Keymodules w/o LED and Keycaps for Keymodules 6425, Series 826 ...
These caps are available w/ printings (for the numwerical keypad p.ex.) and w/o printings, grey colour and 16mm spacing.
Download here ...
http://www.marquardt.com/docs/index.aspx?id=23496&domid=1035&sp=E
Marquardt standard switches overview
Marquadt standard switch catalogue
(both english and german langage available)
... and look yourself
unfortunally, there are no technical drawings in the catalogue and up to now I´ve found no dealer to buy one sample to compare w/ a original.
It would be great to have a guy here in the group who´s able to do more accurate measuring w/ his Xpander/ M-12 than I did,- and to get the tech drawings it might be necessary to organize a group buy before asking the manufacturer I fear.
I doubt the company would sell a single or only a few items.
Unfortunally, my technical english isn´t that good to describe the exact measurements of the originals here but maybe someone else could do,- I hope.
There are the contact pins, their separation distance (5mm) and their horizontal position (don´t know how to describe without a tech drawing, it´s somewhat special in this case), the overall size of the switch (16x16mm),- mounting pins and their separation distance (14mm) as well as their horizontal positions (diagonally: left upper corner /right lower), the separation distance of the caps mounting pins (8mm) and horizontal position,- and height of the switch (9mm).
I used a sliding caliper but won´t guarantee the precision here,- it was not so easy w/ the built-in original switches .
It would be great someone would double check and eventually upload a tech-drawing of the original into the files section ! - But next is to get a sample and/or a tech drawing of the replacement for a comparison.
O.T.:
I have the same prob w/ a Oberheim XK, have all the values but don´t even know the manufacturer of the original switches because it´s nowhere documented, so it´s much more tricky.
Am 14.07.2010 00:37, schrieb mirror_saw7778:
Looks like I also need to buy new switches for my Matrix 12, a few of the buttons are completely dead and attempts to clean them are not working. The little removable rubber membranes inside are damaged (rotted).
Does anyone know where I can buy some replacement switches? I checked http://www.vintageplanet.nl/ but he does not seem to have any, nor does ebay.