Atlas ALCO RS-1

Scale:
HO Scale


This installation uses the following decoder:

A4X



This installation of TCS A4X Decoder is for HO Scale Atlas RS1 and was performed by N.G. and J.M.

Please note: while this locomotive is manufactured by Atlas the frame is made by Kato.

First, remove the shell by squeezing on either side of the locomotive and rocking the shell back and forth until it lifts from the frame.
First, remove the shell by squeezing on either side of the locomotive and rocking the shell back and forth until it lifts from the frame.
Next, remove the default lighting board from the frame and attach orange and gray wires to the motor tabs as shown above. Shrink wrap the tabs so that they won't short out the decoder. The next section depends on whether or not you have a new A4X or an older A4X. The newer A4X's have onboard resistors, and the older A4X's do not. I will refer to these as Style A: New A4X with onboard resistors Style B: Old A4X WITHOUT onboard resistors. Style A: Solder two blue wires to the common pad as shown below, and attach a yellow and white wire to the pads shown in the picture below and displayed in your literature on the diagram for installing LED's. Next solder the motor tabs to the orange and gray as shown below.
Next, remove the default lighting board from the frame and attach orange and gray wires to the motor tabs as shown above. Shrink wrap the tabs so that they won't short out the decoder. The next section depends on whether or not you have a new A4X or an older A4X. The newer A4X's have onboard resistors, and the older A4X's do not. I will refer to these as Style A: New A4X with onboard resistors Style B: Old A4X WITHOUT onboard resistors. Style A: Solder two blue wires to the common pad as shown below, and attach a yellow and white wire to the pads shown in the picture below and displayed in your literature on the diagram for installing LED's. Next solder the motor tabs to the orange and gray as shown below.
Style B: Solder the A4X to the white, yellow and blue wire as shown below, and diagrammed on your literature. Next solder the motor tabs to the orange and gray as shown below.
Style B: Solder the A4X to the white, yellow and blue wire as shown below, and diagrammed on your literature. Next solder the motor tabs to the orange and gray as shown below.
Next, we used the 2 Pin Quick Connectors and the Surface Mount LED's to attach to the lighting tubes. We connected each LED to a separate two pin connector. Next, we pointed each LED into the light tube and used electrical tape to hold it in place. Style A: You do not need to put any resistors in at this point.
Next, we used the 2 Pin Quick Connectors and the Surface Mount LED's to attach to the lighting tubes. We connected each LED to a separate two pin connector. Next, we pointed each LED into the light tube and used electrical tape to hold it in place. Style A: You do not need to put any resistors in at this point.
Style B: Cut one lead from the quick connector and solder a 680 ohm resistor in series.
Style B: Cut one lead from the quick connector and solder a 680 ohm resistor in series.
Finally attach the other side to the quick connector to the lighting wires from the decoder. Make sure you are properly aware of the polarity so the LED will work.
Finally attach the other side to the quick connector to the lighting wires from the decoder. Make sure you are properly aware of the polarity so the LED will work.

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