Idolon Tech Idolon Tech Keypad Fix Clean and Resto

I'd never taken very good care of my old Yamaha PSR-230 keyboard, so it finally began to have problems, with a few keys not working properly, some not working at all anymore. Fortunately, I found a replacement for it ... a fully-functional used PSR-230 that someone was selling for $39.00. I intended to throw the old one out on trash pickup day, but then decided to try this product as a last resort ... without much confidence, after having read other reviews that weren't very encouraging. I'd cleaned the contact pads and circuit board contacts with denatured alcohol, and followed the product's instructions carefully ... stirring it periodically during the application to ensure that it remained thoroughly mixed. When finished, I thought I'd done a pretty good job, with the 122 contact pads looking "like new". The unfortunate result was that after this "fix", the instrument had twice as many dysfunctional/nonfunctional keys.In this instrument, the keys are connected between two separate I/O ports of an 8-bit CMOS microcontroller which, I suspect, measures the striking timing and force in order to provide a touch response feature, like a conventional piano. This simple "fix" is probably not compatible with a switching system with this level of complexity.