[KB-029] How do I connect an arcade coin door to a 3-pin USB encoder without soldering?

Product: Arcade Coin Door / USB Encoder | Platform: Raspberry Pi / RetroPie | Confidence: High

Answer:

Use a converter cable to connect the 3-pin button connections from your USB encoder to the .187 terminals on the coin door switches. This allows a solderless connection between standard arcade components.

Recommended Converter Cable: https://www.ebay.com/itm/296426383604

This cable converts the 3-pin arcade button connector (used by most USB encoders) to .187" quick disconnect terminals that fit standard coin door switches.

Xgaming sells replacement coin door harness cables separately for $5, with a shipping cost of $8.

The coin door can also be wired to encoder boards such as Ultimarc Ultimate I/O. Treat the coin switch like a standard button input on the encoder; use the matching quick-disconnect or harness adapter for the switch terminals, then map that encoder input as the coin button in the software.

For EURO coin mechanisms: Visit Suzohapp NA website for compatible EURO coin mechanisms and adapters. The X-Arcade coin acceptor may work with tokens that have very similar physical properties to US quarters, but compatibility depends on the token's exact specifications, including material, thickness, diameter, and weight. Xgaming can verify token compatibility with their manufacturer if provided with these specifications.

Xgaming does not keep replacement coin-door keys in stock. If keys are lost, replace the lock cylinder or drill/remove the existing lock. A tubular cabinet lock or a Happ D25-style lock may work depending on the coin-door model.

The X-Arcade single coin door is compatible with Arcade1Up cabinets, but installation typically requires enlarging the front kick panel cutout and may require reinforcing the back of the panel with an additional backing board due to the thin MDF material used in those cabinets. Xgaming provides a video tutorial for installing the Arcade Coin Door into Arcade1Up cabinets at https://youtu.be/893itbM3fYU. To integrate the X-Arcade coin door with an Arcade1Up cabinet, the coin switch inside the door should be wired to the same connector used by the original Arcade1Up coin button on the PCB; this allows the coin mechanism to simulate a standard button press when a coin is inserted. Note that Arcade1Up pushbuttons typically use .110 terminals, while X-Arcade DIY kits use .187 terminals; because of this difference, they are not directly interchangeable without adapters or rewiring, and stock Arcade1Up terminals generally require modification to fit X-Arcade hardware.

The coin door and coin mechanism return buttons may exhibit loose physical alignment or off-center movement by design; this is expected behavior and not a hardware defect. To resolve off-center movement or catching in the coin return button, install one M3 washer (1 mm thick) and one M6 washer (1.5 mm thick) on the screw that holds the bracket on the back of the coin door, placing them between the screw head and the bracket. If a coin mechanism rejects coins after shipping, inspect the mech from inside the door and adjust the circled screw clockwise to create more space for the coin path; one confirmed case required several turns before the coin passed correctly again.

Evidence: Support thread 2025-05, keywords: coin door, 3-pin encoder, Raspberry Pi, converter cable, .187 terminals. Support thread 2025-06, keywords: coin door button alignment, felt washer, off-center button. Support thread 2025-08, keywords: Arcade1Up installation, kick panel, backing board, coin switch wiring. Support thread 2024-10, keywords: Ultimarc Ultimate I/O, coin door, encoder compatibility, coin button input. Support thread 2024-10, keywords: lost coin door key, replacement lock, tubular cabinet lock, Happ D25