This circuit is the one that steps the player unit forward to the correct rivet:

RF player unit color (resized).JPG

I've taken out anything related to the game's reset, since that seems to be working correctly. The remaining path is outlined in red. Any of the switches in the red circuit will cause problems with the player/ball count if not working. I'd look at the U, P, BX, Motor 1A, Z1 and Z2 switches. Use the wire colors to identify the correct switches.

Is your U (First Ball) relay pulling in when you score your first points? You might also check your trough switch to see that it's working correctly.

Have you used a piece of jumper wire before to help troubleshoot? That would probably speed things up, if you're familiar with how to use one to short various parts of the circuit to eliminate switches. For example, if you hooked a jumper between the 2 points marked with purple X's below, and then the machine worked correctly, you'd know the problem was with either Z1 or Z2 - the switches you had shorted across and taken out of the equation.

RF player unit color jumper (resized).jpg

Yeah, seeing that someone else has been inside the machine before me scares me more than anything else. Normal age-related problems I can can handle...but God knows what some folks are doing inside there. Good luck!

Let me know what you find out - I'll be curious. Wish I could help more.

Okay this probably a stupid question. How do you jump a motor switch? What does P2G P3G indicate on the schematic.
Thanks
Frank

Frank,

On Gottliebs, when you see switches labeled something like P2G, P3A, P4E...those are switches that are on the player unit in the backbox. The player unit has switches in stacks that ride on the edges of several cams that all rotate together when the player unit gets a signal to fire. The switches open and close in a repeatable order as the player unit rotates. In that sense, it's much like the score motor, except that it's driven by a ratchet mechanism and solenoids, rather than an actual motor. Mechanisms that rotate that way are called steppers, as opposed to the score motor.

The "P" indicates it's on the Player Unit, the number indicates which cam the switch is riding on, with Cam 1 being closest to the steel ratchet. The last letter indicates the level of the particular switch in the stack, with A being the lowest level, and going progressively higher, or farther away from the cam edge.

You can jump a score motor switch (or any switch) by having a piece of wire with alligator clips on both ends, and clipping them on to the tabs on the back of the particular switch you're trying to bypass. If you can't get to the switch tabs (sometimes, there's very little space) you can follow the wire out from whichever side of the switch your interested in on the schematic and clip it somewhere else along the same piece of wire, since that piece of wire and the tab are electrically connected (theoretically, anyway). Jumpering is useful in "forcing" a switch or section of a circuit to be closed, to see if that changes behavior and helps you find where the problem lies.

PLAYER UNIT SWITCHES (resized).png

Thanks for the quick reply. That is what I thought about the P designation. I have jumped coils before. I did not realize you could jump individual switches. So the power comes from the coil on the player unit and jumps to the individual switch stack.
Thanks
Frank

Hey Frank,

Power (or electricity) doesn't come from the coils. Coils are just what they sound like - coils of wire that don't do anything until electrical current passes through them. Then a magnetic field is created and that field pulls in a metal plunger or pulls a metal plate to do work - eg. make a flipper move, make the player unit step up one time, pull in a relay armature, etc.

There is a voltage differential between the 2 sides of the transformer (another more descriptive name for voltage is "electro-motive force" - it's an electrical force that "pushes" electrons through a conductor. If you think of the analogy of water going through a hose, voltage is the water pressure, current is the actual flow of water, and a narrowing or kink in the hose that resists the flow of water could be resistance.). On the schematic, if you trace the wires from both ends of the transformer, you'll see that the wires travel up vertically on both sides of the 25V section of the schematic on the right, and the 6V section on the left. If you trace a path between the 2 vertical wires, through any coil, and through all the switches that are in series with it, the job of those switches is to turn on the coil in certain conditions by closing and allowing electrical current to pass through the coil, which turns it into a electro-magnet and allows it to do work. If a coil isn't turning on (having current pass through it), then either the coil is burnt open, there's a bad solder joint, a broken wire, or one or more of the switches aren't closing or making electrical contact when they should. By jumpering, you're trying to narrow down the area where the problem lies. Then usually, you have to get in there with your eyes and see what the actual problem is.

I'm sure there's a much better description of basic electrical behavior out there - MarkG is always very helpful and could probably steer you to one - in fact, he has a great site that you should probably look at that explains these things and how they're related to pinball very clearly (https://www.funwithpinball.com/) - plus it's just fun to go through! It would be a good idea for you to read a little about it - it makes troubleshooting easier if you understand the big picture of what you're going for. And you don't have to be an electrical engineer to work on EM's....just have some basic electrical knowledge and be able to think logically.

Good luck!

I understand that the transformer provides electric current to the machine. I was under the misunderstanding that the coil activated the switches. So when I jumper power to diagnose a switch stack I have been jumping coil to coil not coil to switch stack. So in my case all the coils I have jumped have been good in the above schematic. So in the above schematic I would jump the player unit coil to the to the BL-WH-Red wire in the 1A motor switch and that should activate the switch?

Thanks

https://www.funwithpinball.com/learn/switches-and-electric-current

Sounds like you're close now. The U relay is supposed to energize when you score points on your first ball (that's when either the L, M or N switch closes). Once the U relay energizes, it's supposed to stay locked on through its lock-in circuit outlined in green in the snippet below.

RF U circuit (resized).JPG

If it's not locking on, then you only have 2 switches to look at - one on the AX relay and one on the N relay. I'd guess it'll wind up being the AX switch since those AX relays have so little motion and are hard to see clearly if the switches are opening and closing.

Once it's fired, the U relay should stay energized until the AX switch opens again, which wouldn't happen until the next game reset.

No, once you've scored points, the U relay should stay energized until the end of the game - I think you're misinterpreting that sequence of operation. Looking at the schematic, there's no way for the trough switch to turn on the U relay - it only turns on the P relay, which is when player/ball advance should happen. But it won't happen if U has relaxed. (See snippet in post #4)

You have to figure out why U is relaxing. Check those 2 switches (U and AX) in post #16 in green. Is your AX relay staying energized the entire time? Once the game goes through its reset sequence and starts, that AX relay should be in the same position the rest of the game.

Which one...Moe, Larry, Shemp or Curly? Nyah, nyah, nyah.

Glad you got it worked out. Those AX, BX, CX relays are touchy little things. There's so little motion to begin with that any little thing that reduces the amount of armature travel will cause you problems....you have to make sure everything's clean, moving freely, and possibly bias the switches a little to get the maximum armature movement, then life is easier. Even though they're a little tough to get dialed in, if you manage to do it, they do work well for a long time.

Hope you get to play the game now, if you're not sick of it already! It's a great game. Ed Krynski said it was his favorite of his own designs.