Hi
Keyboard contacts aren’t an impossible DIY task on some.
But it depends on the make and model.
One of the more successful ones are older Yamaha psr types .
The contacts are usually in strips of about one octave.
They are made of rubber and like a row of bubbles inside of which are conductive pads , these press down on to what is often a printed cir. Gold plated pair of contacts.

Their worst enemy is dust and smoke and the pads loosing their sticky and falling off the rubber strip onto the contacts and shorting out permanently, hence your high 127 ones.
Some folks say a blast with an air! can believe me it seldom works for one thing if the rubber is any good it will prevent you getting the air where needed.
Removing the pads and cleaning the gold contacts, then putting the old pads back, might work but while you spent all that time it is better to change the pads .

Which brings you to finding a source for the spares normally only the manufacturer.

In all cases you will have to separate the keyboard clam shell remove the keys keeping them in strict order of layout as the have different shapes, and weight if a weighted keyboard.
Not for the faint hearted unless you are good at such things.
Also look out for interconnections between the top and bottom of the shell case.

Mike


Last edited by Mike Head; 02/08/20 11:29 AM.
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