Hi,
I recently posted on here about a keyboard I was trying to repair. Some of the keys were connected to each other after a spillage.
Today I was looking for the cause of this, when I noticed something I don't really understand.
When I connect the membrane trace that is causing problems to one end of a wire with a ferrite bead that is connected to a capacitor near the LEDs on one side and to the membrane and microcontroller on the other, It works absolutely perfectly for about 5 minutes.
After that it goes back to keys being connected or one key being pressed infinetely (always the same key)
What could be causing this? I'm thinking perhaps a bad capacitor, but I don't know how plausible this is.
P.S.: I circled the ferrite bead in the picture of the circuit, I connect the trace with the bottom pin for the 'reset'