On the woodrails, the Start relay is activated via a path that includes:
- the main line 5A fuse
- a normally closed switch on the Start relay switch stack
- the coin door start button closing the switch behind it
- the credit unit having a credit (so that the zero position switch is closed)
- a normally closed switch on the ball release gate switch stack
Alternatively, the coin chute switch can close, bypassing the coin door and credit unit switches.
When the coin door start button closes the switch, then the Start relay activates. This then actually completes a path to the transformer (the previous path being straight 110V line power).
Once the transformer is activated, then the Hold relay ('R') activates via a normally closed 'knockoff' switch. The knockoff switch is mounted on the score motor board over a small shaft that bounces up when the bottom of the game is slapped, turning off power.
The Hold relay activating closes its own switch, keeping power to the transformer active until the knockoff is hit, or the game is unplugged.
With the Start relay still active, if the 100K unit is not already reset, then the Reset relay ('Z') activates via the normally closed 'Minus 1 position, 100K unit" switch. (This switch is on the backside of the 100K unit.) When Z activates, then the score motor will start running via a switch on Z, and a normally closed switch on the Tilt relay switch stack.
The Reset 100K coil is activated via the 'minus 1 pos. 100K unit switch, score motor switch 1C, and a switch on S while it's still activated. This coil fires once, and the return spring on the 100K unit zips the wiper arm back to the -1 position.
With Z still active and the score motor running, the "Add 10,000" unit coil is activated via a switch on Z and score motor switch at 1A pulsing closed (5 times per 1/3 rev). There are three 'zero' positions on the 10K unit; when one of them is reached, then the 100,000 point relay (M) is activated via the
'on add 10,000' switch (also on the backside of the 10K unit), and M in turn steps the 100K unit one step to take it from -1 to 0.
At this point both the 10K and 100K are reset to zero.
Another switch closing on Z activates the Ball Release coil, which then lets the five balls out of the trough to feed the lift. The ball gate stays active until some points are scored.
Z de-activates once the -1 position switch on the 100K opens.
So that's basically how a Gottlieb woodrail starts up and resets.
Good luck!