I recently purchased a Xenon, my FAVORITE when I was a kid...the coin mechs were missing -- didn't think much of it at the time, as it was set for free play anyway. But after watching a couple of YouTube vids, I wanted the "Ahhhhhh!" coin drop sound back. The machine came with a newest version Alltek board, and I've recapped both the SOUNDS and VOCALIZER boards, plus installed Visaton FR-10 speakers -- she sounds GREAT otherwise. Picked up a beat-to-hell coin door from e-bay that had a usable coin mech, and popped it in, to no avail.
All wiring appears to be intact from the door to J1, but even manually tripping any of the three coin drop switches will not produce the sound. Does setting the MOBO switch to 'free play' disable the drop switches, and therefore prohibit that delicious sound byte???