TCS 1557 | B-MB4 21-Pin Motherboard w/ Keep-Alive - Bachmann 4-4-0 & Brass | HO Scale

The TCS B-MB4 is a replacement motherboard for the Bachmann Richmond 4-4-0, accepting a 21-pin WOW121 or EU621 decoder for a quick, clean install. An on-board KA2 Keep-Alive® keeps the little 4-4-0 running smoothly over dirty track and frogs, and the universal layout also makes the B-MB4 a great choice for brass models. Browse more DCC Accessories and DCC Decoders, or shop the full Train Control Systems lineup. Choosing Your Pin Height The B-MB4 ships in two 21-pin connector heights so the board seats correctly against your decoder. Choose Low Pins for TCS decoders (WOWSound 121, EU621), or High Pins for Soundtraxx & ESU decoders — just match the option to your decoder’s brand. Features Replacement motherboard for the Bachmann Richmond 4-4-0. Accepts a 21-pin WOW121 or EU621 decoder for fast installation. On-board KA2 Keep-Alive® for stutter-free running. Universal design — also well suited to brass model installs. More Information Brand Train Control Systems (TCS) Item Number 1557 (B-MB4) Type DCC Motherboard / Decoder Interface Decoder Interface 21-pin (WOW121 or EU621) On-board Keep-Alive Yes (KA2) Fits Bachmann Richmond 4-4-0; universal / brass Scale HO Scale Condition New FAQ What does this motherboard do? It replaces the factory circuit board so you can drop in a 21-pin WOW121 or EU621 decoder, and it adds an on-board KA2 Keep-Alive for smooth running. What locomotive is it for? It is designed for the Bachmann Richmond 4-4-0, and its universal layout also suits many brass models. Does it include a decoder? No — add a WOW121 or EU621 decoder to complete the install.