Older Athearn AMD 103

[PFK57]

I have an older Athearn AMD 103. Per MR September 2005, the older units did not have a DCC quickplug. I have verified this in my model. Being new to this whole area (DCC), is it possible to install a decoder in these older units, same question for a model Power RS11. I do not want to buy new locomotives if possible.

Thanks for any help

PFK57

[Anonymous]

Yes, it's possible. There was an article in MR from 2003 or early 2004 showing how to install decoders in earlier Athearn locomotives.

[Anonymous]

The Athearns are very easy to add DCC to, I'm not so sure about the MP RS11 though - the important thing for DCC is whether you can isolate both motor brushes from the power feeds, if you can do this (check with a multimeter) you can add DCC.

[modelmaker51]

It is certainly possible to wire both locomotives for DCC.

With the Athearn you must first isolate the motor from the frame. Remove and toss the metal strap that connects the trucks and moter. With a flat headed screwdriver, pry off the retaining clips on the trucks that hold the worm gears and universals in place, remove the drive train and trucks from the frame. Then, holding the frame in one hand gently wiriggle the motor while pulling it away from the frame. Once the motor is free, turn it bottom side up and you will see a copper colored piece of metal that runs across the bottom with 2 prongs sticking up. Slowly, from one end, pry that off. Be careful as the motor brush and spring are underneath and will want to go flying across the room.

Set the motor aside and either cut the prongs off with side cutters or pound them flat with a hammer. Next, solder a 2 or 3" lead wire to it and then reassemble the bottom. Repeat this with the top of the motor. These leads would then be connected to the motor leads on the decoder after reassembling the drive.

I would recommend hard-wiring the trucks at this point as well. There are 2 ways to do this depending on your soldering skills.

The simplist: Drill a hole in the frame for a self-tapping screw, make a 2 or 3" lead, strip a half inch of insulation and tin it, then wrap that around the screw and screw it into the frame. Second, connect the posts on the two trucks with another wire. The leads on the decoder that go to the track connects to these leads.

The other method: Remove the sideframes from the trucks and you will see 2 brass rivets/grommets on each side of the trucks, solder a 4" lead to each of these rivets closest to the center of the locomotive. Connect the pair of each side together and then to the decoder.

Since the loco is disassembled, now would also be good time to replace the sintered-iron half axels with NorthwestShortLine's nicklesilver wheel sets for better electrical contact.

These instruction cover pretty much all the Athearn BB engines. I hope this helps and if I forget anything I'm sure someone will chime in.

[modelmaker51]

If the MP unit is one of the old ones with the plastic frame and only has one wire lead coming from each truck, one would have to add another set of wheel wipers and lead to each truck for good operation. With pickup from only one side of each truck you're not going to get very reliable operation. DCC requires good continuous contact with the track.

I think you would be better off buying an Atlas or LifeLife Proto2000 RS-11 (check ebay for a good buy), that is either easy to convert,(the Atlas), or already DCC ready (The P2K).

[PFK57]

Thanks, everyone. I will see what can be done.