TCS recommends using the DP2X-UK decoder for simple plug-and-play installation.
This installation documentation is for the HO Scale Roundhouse EMD Model 40 Critter. The original installation uses the MC2 decoder, and was performed by a TCS customer.
Important note! The directional lighting diodes mounted on the locomotive DCC plug board are mounted backwards! Do not plug a decoder into the socket and turn on the lights. You will instantly fry the decoder! In later versions of this locomotive, Roundhouse corrected this issue. Unfortunately, there is no way for us to know when exactly this problem was corrected, but you can test this by reading the polarity of the diodes to be sure the light functions are not tied directly to the track.
Please do not use any flux either liquid or paste on the mother board. Over time, the acidic properties of liquid or paste flux will begin eating away at the fiberglass PCB and will damage it. Use only Rosin-core solder or no-clean flux approved for electronics use.
TCS recommends the use of Kester "44" Sn63 Pb37, .015" diameter Rosin-core solder. Kester part number 24-6337-0007.
When stripping wire, only strip a tiny little bit of the insulation. Strip no more then a 1/64 of an inch. When the wire gets tinned with solder, the insulation will shrink back more. Try to not expose any more wire then half the length of the solder pad at most. In no case should solder or exposed wire wire ever be outside the boundary of the the solder pad you are attaching a wire to.
Click here for important information on properly Stripping and Tinning wire