Old school 40h kit ghosting problem

Good morning,

Are there any old school 40h kit users/builders who have experience in fixing ghosting issues? I have been using my old 40h quite a bit lately but it is ghosting a lot on one row. I have disassembled it and cleaned it well but that did not fix the issue.

I have seen in some ancient archives that replacing a particular resistor may be the cure?

Has anybody done this?

can you clarify what you mean by ghosting?

do you mean poor key detection? or flickering?

“ghosting” for key scanning matrices refers to incorrect key detection: bleed between rows. which shouldn’t happen given the grid design uses diodes per key.

Ahhh, sounds like it is not ghosting maybe.

Symptom is when using the 40h with re:mix/mlr there are one/two rows that are triggering themselves. Spontaneous triggering basically.

edit: I have traced it to one pad that is triggering itself. Maybe disassemble and lightly sand that one? Clean the PCB with ISP?

edit x2: I loosened the fasteners in the area of that pad and as of now the issue is not appearing. Looks as though it was the pad being too compressed. Hopefully that cures it for good!

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