Atlas ALCO RS-3

Scale:
HO Scale


This installation uses the following decoder:

A4X



This installation of TCS A4X Decoder is for HO Scale Atlas RS3 and was performed by Les Cattin of Vintage Hobbies in Kokomo, Indiana.

I used an A4X for the installation. The old Atlas setup had the single light bulb in the center of the board. Most people cut and polish the light tubes to the length that is needed, but what I did was use two small incandescent bulbs side by side in the same spot in the center of the board. I made a "T" out of electrical tape between the 2 bulbs which mostly isolated the light from the front bulb from brightly lighting the rear light pipe. I assembled the loco, and the light in the direction of travel, of course, is on. You can see it both front and rear but the opposite light tube isn't getting as much light so it is automatically dimmed. What you end up with is a very nice dim glow in the opposite light. It works great. I am also going to disassemble the trucks and solder the pickup wires to the wipers. The original Atlas design used a push on the cap to attach the wires.

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