Atlas GP-38
A6X decoder Installation

 Photo by Craig Zeni

The mechanism with the front weight and old decoder removed. The
weight must be removed to get the old decoder out and new decoder in.
At this point I tinned the wire ends on the locomotive.

The mechanism with the TCS A6X decoder installed and the wires soldered
in place. I use a 25 watt iron with a clean tip and a high quality
rosin core solder. Note that it may be necessary to *carefully* file
the mounting holes in the decoder to get it to slip over the plastic
clips on the mechanism. I had to square up the holes a little bit with
a square rat-tail file, taking great care not to damage any decoder
components or traces on the circuit board.

This photo shows both LEDs installed and the front weight fitted. Note
that the shell will not clear the rear light as shown here - the wiring
must be flush with the top of the weight. In the photos the resistors
are exposed so that the viewer can see what I have done. Before
finishing the project I will cover the resistors with heat shrink
tubing as seen on the LEDs.

The almost completed installation - the last step is the heat shrink
tubing for the resistors. Put the engine on the programming track to
make certain there are no shorts, program and enjoy the way the decoder
makes this engine perform.