Vintage Synth Repair

I had a bad joint on a keyboard scanner IC in a yamaha AN1X; every fourth key wouldn't work, or something- I forget the exact symptoms.
 
this enormous surface mount processor with about twenty pins on each of the four sides.... & one connection was slightly *lifted*. 

you'd never see it from the top- look at these ICs edge-on too, to see if their legs are all touching the board. a jeweller's loupe or one of those usb microscopes are good for this type of work.

duncan.