My Black Hole has been intermittently blowing the fuse on the 24 v supply. Finally decided to do the ground mods, test, resolder and repin as needed. Large transistor Q 64 has a dark area of the board, showing heating. On the back of the board about a 1.5 by 3 inch area has been spray painted rust color and the outline of the transistor is showing heat damage to the fiberglass mat in the board. Paint is on the screws and nuts, so done after the last Q64 replacement. I'm guessing the paint was to restore a cover on the traces?
Four drivers in a row have been resoldered or replaced 17, 18, 20, 19. These all run lights or relays. Board has good solder except for vias on the edges.
Any thoughts appreciated