I, apparently, have been chosen to be the king of the intermittent problem ... a simple circuit, yet the ball count does not always advance, stopping intermittently, sometimes for a couple plays on a ball (varies). After doing all of the regular checks, such as cleaning contacts, jones plugs, replacing the trough switch, I started testing with jumpers. Jumping from the BLU-B on the Ball Index relay to the RED-B on the Outhole relay always made the ball count advance as it should. RED-B to RED-B did not. To rule out broken wires, etc. I jumped the BLU-B and the RED-B on the Ball Index together and the ball count always advanced correctly (although first ball up made it go to '2'). Sooooo, I figured it had to be the sw. and replaced it. No. Ideas?
The whole schematic is here: https://www.ipdb.org/files/1245/Williams_1966_Hot_Line_Schematic_Diagram_continuous.pdf
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