Description
  • It gets caught in the startup sequence. So what do I see?
    - I press the replay button.
    - That energizes the Start coil, which changes the state on the Start/S relay pair
    - That starts the score motor running
    - It resets the horse sequence units with a switch on Motor 2D
    - It loops on this forever
  • If I force trip the S relay, then it
    - resets the scores
    - energizes the ball release coil
    - that stays energized until I hit something that generates points
    - from here the game plays as normal
  • Also involved is the Z or Reset relay. That is triggered by the “minus 1” position on the 100,000 stepper. So I guess something kicks the reset solenoid on that?
  • So what’s the whole sequence?
    - replay button
    - start coil, flipping S switches
    - disables the start button
    - enables the score motor?
    - both
    - enables subtracting a replay
    - resets the 100,000 to minus 1
    - the 100,000 minus 1 switch triggers the Z/Reset relay, which
    - triggers the ball release
    - starts the score motor
    - enables the flipping back of the S relay when the score motor hits 4C
    - subtracts a replay at 1C
    - activates the horse resets
    - triggers the T and Counter relays
  • When I started this debugging, I knew one of the switch stacks was bent way out of true. But I discounted it as probably irrelevant, because I thought it had to have been that way before. However, bending it back and fixing the switch alignment fixed the problem. I did adjust some wire positions, so maybe there was a compensating short?
  • The machine is now back to being playable. There are a number of small things, one of which is that the backbox lights are a little off because the wood has worn or has bits missing. I used some putty to hopefully fix it.
Media

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