I found that my Duotron pinball machine has a Y relay which is labeled 2 coins per play. The 2nd coin chute adjustments include an option for 1 or 2 coins. I'm familiar with the Y relay being used when there are 3 coin chutes on a game to enable two coins for 1 play for the nickel coin chute. I've never seen a Y relay for the second coin chute which is intended for quarters. Considering that Duotron was made in 1974, why would this option have been available? It was too early for 2 coins for 3 plays.