Okay, so I recently purchased a silver badge M122 off of ebay for a decent chuck of change. It was produced in Nov1987, so a pretty old one, and when I got it and hooked it up to my converter I got nothing. No keystrokes or locklights. fearing the worst, I cracked it open and lo and behold, a horrible stench of mold and mildew made by water caught between the barrel plate and metal backing place erupted out. The barrel plate's plastic rivets that remained quickly gave way and the metal backplate fell away.
I cleaned all the salvageable parts up, such as the controller and barrel and backing plate, thinking I could just call up unicomp and get a replacement membrane shipped in and bolt mod it and be done with it. Alas, when I called and they searched for any compatible membranes, they had none in stock! They were long gone, I assume sold to people in the same predicament as I a long time ago. So I had a broken bunch of vintage keeb parts with no replacements. I thought about using the refitting services via the Unicomp website, but decided I wanted to try something different first.
So I called up Unicomp and purchased a set of the newest controller, usb cable, membrane and rubber mat, hoping that as I had read that the designs have been mostly unchanged over the years (thank you Chyrosan22 for your Model M Anthologies). As I had hoped, they matched the old backing plate and barrel plate almost perfectly! Additionally, the connector ribbon for the pcb-ribbon contact interface came out along the righthand side of the metal plate, where there is an open space within the case.
Again, perfect! This becomes the perfect space for a controller - membrane ribbon connector interface mount. After experimenting with a hanging mount and bracket design that hangs off of the metal backing plate with two slotted arms and holds the controller in place on the ribbon with two bolts and a flat bracket, I printed it off and fitted it.
It works fairly well, you just have to play with the tension of the bolts and the upper part of the bracket to keep constant pressure on the ribbon so all the keystrokes are captured.
Haven't gotten around to posting up the printer files yet but I don't have a problem doing so. All in all, if you have access to a 3dprinter this project will only cost you about $60 US dollars, including the hardware.
