Repair of TP400/Wood keybed

[Schorsch]

Hello,

I am looking for a Studiologic SL88 Grand controller as an additional to my NS3C for playing the piano engines. I can get a second hand SL88 at a quite low price but 6 keys are having a malfunction, they either don’t work at all or just sporadically. The keys in question are C#4 to F#4, so 6 keys in a row. Does anyone here have an idea of what’s probably damaged and some experience on how to fix this, and may this a big issue or a relatively simple task for DIY?

Thanks for any kind of response and help

[maxpiano]

It could be the connectors between the keyboard and mainboard,first of all (I'd suggest to the current owner to unseat and reseat the flat cables on both sides); if still not working then it could be a HW mulfunction at the level of the scanning circuit (not selecting that row of the keyboard diode matrix properly or a broken diode) which requires some electronics repair skills to diagnose and fix.

[Schorsch]

Thanks Max,

the current owner seems not to have any skills to open it and check the connectors. I do have some electronic skills and think I’m able to repair by myself to some extent - I will think ….

[maxpiano]

Thanks Max,

the current owner seems not to have any skills to open it and check the connectors. I do have some electronic skills and think I’m able to repair by myself to some extent - I will think ….

You can find the schematic of Fatar TP40/88 at doepefer.de site

https://www.doepfer.de/DIY/Matrix_88.gif

this may help you to focus on the part of the matrix related to the non working keys.