Recently picked up the schematic for my new-to-me Gottlieb Domino which has been playing fine in 5 ball mode, and starting to poke around a bit under the hood.

The schematic led me down the rabbit hole of 3 Ball vs 5 Ball, there's a honking jones plug strip to make that change, and it seems to impact a lot of the playfield, and I wanted to check it out.

So far:

5 Ball: 2 of 6 top lanes light (alternately), pop bumpers alternate (red / yellow), and center target turns on periodically (1 of 3 cases)

3 Ball: 2 of 6 top lanes light (alternately, no change), pop bumpers alternate (red / yellow / all), and center target is always lit

Not sure if all this is right, but it seems (mostly) right. I'm have not noticed or dug into any differences in the captive holes (spin & advance), the roto targets themselves, or the side drains (advance) or center drain (spin).

I'm also looking at the Domino Advance setting (conservative vs liberal) and as far as I can tell, I'm not seeing much impact there. Base on the schematic, I'm guessing it impacts what will advance the dominos, but have not noticed it yet. The purported 3 ball / 5 ball instructions (3 ball instruction card not verified) show no differences, nor do the playfield instructions or schematic.

Y = (Captive side) Hole Relay
X = 100 Pt & Advance Relay
V = Roto Target Scoring Relay

Any Domino owners have a manual, other documentation, experience, or link to a thread here that might let me know what it SHOULD be doing?
Domino Advance Option (resized).jpg

3 Ball vs 5 Ball (resized).jpg

Thank-you, useful. Your way of looking at / describing the relay logic makes things more clear.

So...the X relay is the main show, being energized by: lighted lanes, lighted targets, hole relay, lower rollover relays (side drains), as well as the roto unit when the domino matches. Trial and error provides the following:

5 Ball / Conservative: One advance per roto-target hit / One advance per captive hole capture via Motor 4C

5 Ball / Liberal: Two advances per roto-target hit / One advance per captive hole capture via Motor 4C & Motor 1B

3 Ball / Conservative: Three advances per roto-target hit / Two advances per captive hole capture via Motor 4C & Motor 3B & Motor 1B (except Y / Hole Relay)

3 Ball / Liberal: Three advances per roto-target hit / Three advance per captive hole capture via Motor 4C & Motor 3B & Motor 1B

Which makes perfect sense from the schematic / your description. All working as it should!

Thanks for the push in the right direction!

Interesting, thanks! I wondered why I could picks one up for Duotron but not Domino....

That's how mine works; so the five spot target is "hot" if it happens to be up.