mattydemont wrote:Changed the wires that wen to the key contacts board ... no result.
What do you mean with this exactly? Did you replace the ribbon cables between the keybed and the mainboard?
mattydemont wrote:I concluded the problem lies in the upper key contacts board. See pics below; arrows indicate the faulty key contacts.
Have you ruled out the diodes at those positions. Judging from the photos (though it is not entirely clear), the tracks on the PCB look fine to me at the areas you point out.
mattydemont wrote:What are my options? Can I order this upper contacts board?
Probably, but it will probably take some work to locate a replacement one. I'm not convinced you'll need a replacement though. If it is the diodes that went bad, they can be replaced (they're really cheap parts). If it is actually the PCB that was damaged (not very likely, you'd probably notice serious damage on the outside of your Nord if that was the case) you could theoretically fix it (by bridging damaged parts). If you intend to replace that part, you might as well attempt to fix it (nothing lost if you fail).
I think your best solution would be to find someone who's handy (enough) with a soldering iron and has a multimeter (this could be you
). Then check (measure) the diodes for the keys that have issues (follow the trace on the PCB from the key contact to the diode).
Have your already done some measuring, have have you just thought about it where the issue might lie (I think there's a good chance you are right)?
If you do intend to try and repair this yourself, I think you'll need:
- A multimeter
- Side cutters (electrician ones will do fine)
- Some (needle nose) pliers (not too big please)
- A desoldering pump (optional, but helps)
- Desoldering braid (can be a more time consuming alternative for the desoldering pump)
- Some 60/40 (or 63/37) rosin core solder (easiest to work with) or some lead-free solder; 0.5 to 0.8 mm thickness would be best, but 1 mm would work too
- And the most important bit: replacement diodes (say 5-10, gives you some room for error and any future repairs, if ever necessary) of the right type
A cheap soldering iron (one that just plugs into the wall socket) would work fine, provided it has a fairly small tip (ideally one that looks like a small screwdriver, say 2-3 mm in width). 15-40 watts should be fine, but 80-200 is overdoing it.
Edit: you won't need much solder and you can often get it in small tubes that contain 50-100 grams, which is
plenty.
