Bachmann Spectrum USRA Light 4-8-2 Mountain Locomotive

Scale:
HO Scale


This installation uses the following decoder:

DP5



The installation is for HO Scale Bachmann Spectrum USRA Light 4-8-2 Mountain Locomotive. It uses TCS DP5 digital decoder and was performed by A.G.

The Locomotive is shown here as a courtesy of Bob Jensen.

The two upper pictures represent the locomotive prior to the decoder installation. The DP5 decoder will be fitted into the locomotive's tender.
The two upper pictures represent the locomotive prior to the decoder installation. The DP5 decoder will be fitted into the locomotive's tender.
Here is a picture of the tender where the decoder will be installed.
Here is a picture of the tender where the decoder will be installed.
There is one phillips screw (circled in red) that holds the tender's chassis and its shell together - remove the screw and gently lift the shell off of the tender's chassis.
There is one phillips screw (circled in red) that holds the tender's chassis and its shell together - remove the screw and gently lift the shell off of the tender's chassis.
Here is a picture of the original light board where the DP5 decoder will be installed.
Here is a picture of the original light board where the DP5 decoder will be installed.
Close up of the original 8 Pin NMRA Plug.
Close up of the original 8 Pin NMRA Plug.
Remove the "Dummy Plug."
Remove the "Dummy Plug."
Plug the DP5 decoder exact the way that is shown above and cut the yellow capacitor off (circled in red).
Plug the DP5 decoder exact the way that is shown above and cut the yellow capacitor off (circled in red).
Place the shell back, reinstall the Phillips screw and we are ready to go!
Place the shell back, reinstall the Phillips screw and we are ready to go!

Important Soldering Tip

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.

You can order this solder from the following retailers:
Digikey - PN:KE1110-ND
Techni-Tool - PN:488SO6775

Other solder tips

When stripping wire, only strip a tiny little bit of the insulation. Strip no more than a 1/32 of an inch. When the wire gets tinned with solder, the insulation will shrink back more. Try to not expose any more wire than 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