Adapter Board 21MTC 8 Amplified Outputs with Pads & Wires

Adapter Board 21MTC 8 Amplified Outputs with Pads & Wires

Details:

The ESU 21MTC Adapter Board 3 is a compact and highly capable interface board designed for installing 21-pin MTC decoders into locomotives without a factory-fitted digital socket. It provides a clean, structured and low-soldering solution for converting analogue locomotives into fully DCC-capable models using ESU LokSound and LokPilot decoders.

Measuring just 30.5mm × 15.5mm, the adapter board is almost the same size as the decoder itself, making it ideal for tight installations inside modern HO and OO scale locomotives. A removable mounting lug allows flexible installation depending on available space inside the model.

The board features integrated amplifier circuitry for AUX3 to AUX6 outputs, which are typically logic-level outputs on NMRA-compliant decoders. These are upgraded on the adapter to provide full power capability (approx. 250mA per output), significantly increasing flexibility for lighting, functions and auxiliary devices. This enables a total of up to 8 usable function outputs, depending on decoder configuration.

For ease of installation, key connections are pre-fitted with approximately 200mm pre-soldered wires, reducing wiring complexity and making locomotive conversions faster and more reliable.

The 21MTC Adapter Board 3 is ideal for modellers upgrading locomotives that do not have a factory-installed decoder socket. By providing a structured interface between the locomotive wiring and the decoder, it eliminates complex point-to-point soldering and ensures a professional, reliable installation.

Its built-in output amplification makes it especially useful for models requiring multiple lighting functions such as directional lighting, cab lights, marker lights, and additional accessory outputs. This makes it a strong choice for both basic DCC conversions and advanced sound installations where multiple functions are required.

Features:

• Converts analogue locomotives for use with 21MTC decoders
• Compatible with ESU LokSound and LokPilot 21-pin MTC decoders
• Integrated amplifiers for AUX3–AUX6 function outputs
• Supports up to 8 function outputs in total
• Pre-soldered 200mm wiring for simplified installation
• Compact design ideal for tight locomotive installations

Additional Information:

• Decoder Interface: 21-pin MTC (NEM 660 standard)
• Function Outputs: Up to 8 outputs (AUX1–AUX6 amplified)
• Output Current: Approx. 250mA per amplified output
• Wiring: Pre-soldered 200mm connection wires
• Mounting: Integrated removable mounting lug
• Compatibility: ESU LokSound & LokPilot 21MTC decoders
• Application: Locomotive digital conversion, lighting control, DCC upgrades

Measurements:

• Length: 31.0mm
• Width: 15.5mm
• With mounting lug: 36.0mm × 15.5mm