Installing the TCS M1 decoder in an Atlas Classic RS1
RS1M1a.jpg

December 2007

Many of the Atlas Classic series releases did not come "DCC ready" and require frame milling to make room for a decoder. Fortunately, Aztec Manufacturing does provide milling service for all of these. For the Atlas Classic RS1 model we will use Aztec Part Number TM3019 and for a decoder we will use the Train Control Systems M1 wired decoder. While this installation is similar to others presented on this site, there are some important differences some new practices that apply to other installations.
Cut decoder wires:

Red = 2 - 1/16 inch
Black = 2 - 1/16 inch
Orange = 1 - 7/8inch
Gray = 1 - 1/2 inch
Blue = 3/4 inch
White = 2 - 1/8 inch
Yellow = 1 inch		 Refer to photo 1 above.

Start by fully disassembling the engine. When removing the motor make a mark on the top of it. Then cut the decoder wires to the lengths listed on the left. Cut the circuit trace in the usual place on one of the LED boards and solder all the wires as shown so you end up with something that resembles the photo. An optional step here would be to replace the stock yellow LED with the bright golden white type. On the LED that is not attached to the PC board, use a file to flatten the ridge on both sides between the leads.
Refer to photo 2 above.

Install the motor brushes orange wire to the bottom and gray wire to the top. With jewelers file that has a sharp edge file a slot across the motor body on the left side of the motor as shown in the photo. The shot should be deep enough so that the orange wire will fit into it a be flush with the motor body. Then route the orange wire as shown use a small amount of Wathers Goo to secure it into the slot.
Refer to photo 3 above.

Lay the motor assembly into the left half of the frame and install the front and rear worm gears and their bushings as shown.
Refer to photo 5 below.

Before installing the contact strips to the frame, inspect them for tarnish and if needed, clean them with an eraser. Pay extra attention to the part that contacts the trucks.

The Atlas Classic RS1 has 4 contact strips. Most other models have only 2. This is a good practice for all installations.
Refer to photo 4 on the left.

The Atlas Classic RS1 does not use the plastic motor mounting frame like most of the Atlas releases. Instead this model uses the same type of motor mounting rings that the old Kato made model used. Take extra care to insure that the tabs on the mounting rings are properly seated into the slots on the frame.

Then re-assemble the two sides of the frame. Don't forget the shoulder washers that go between the two sides and the clip on springs that go on the right frame side.
Refer to photo 6 above.

After the contact strips, fuel tank, and trucks are assembled the frame assembly should look like this. Lay the LED that has the flattened ridges down on the frame on one of it flat ridge sides then lay the decoder on top of it. Secure the decoder with a piece of scotch tape.
Refer to photo 7 on the left.

If everything is right, the shell should fit on the frame with the tabs on the frame touching the shell as shown in a total of 4 places. This is critical for the coupler height to be correct.

For clarity the photo shows this with the trucks and contact strips removed.

END