I just installed the 2nd of 3 Soundtraxx decoders I received as a Christmas gift, Christmas 2005. After the installation I put the locomotive on my track and everything worked fine. I turned all the volumes all the way up, changes the address and the horn tone. Everything was working fine. Ran the engine around a little everything worked fine. The next day I turn on my MRC Prodigy Advance and both locomotives on the track the sound comes on. I move another locomotive around a little. Then I changes to the newly installed locomotive. As soon as I tried to move it forward it completely stopped. No Sound and will not move. I have tried to do the factory reset but it is not responding to anything. I have tried many times. I have also looked the installation over and cannot find any lose wiring or anything done wrong. This is on a Athearn blue box probably from the late 80’s early 90’s.
I put the locomotive on a program track and tried to read the address but it comes up blank. Do you have any suggestions?
Can you undo the black and red leads and clip them to the program track without the wheels sitting on the track. That way you can get an idea if the decoder is working.
Is it possible to install a decoder and not have the motor isolated properly and it work correctly for a while? I talked to Soundtraxx thru email and he sadi I have done all the trouble shhoting it needs sent into them. Im mainly worried about this happening again on this old Athearn Locomotive. But I really want to get it working. It is the old Ornage and while ICG I used to see as a kid. I cant think of the model number U-something.
If you have a multi-meter, you can test for continuity and see if there is a short. Put one lead on one of the engine’s poles then put the other on each side of the engine’s wheels on each truck. Repeat for the other pole. You should not get continutity. If you do you need to start looking.
Unfortunately, that’s possible. If this is an old Athearn with a metal frame and metal trucks, you may have been lucky at first, perhaps as long as the engine was on a straightaway. Then, the trucks were away from the frame. As you got to a curve, the trucks would turn and possibly brush against the frame, shorting thus applying voltage to the frame and shorting the decoder.
Another possibility, particularly with an old engine, is that the motor draws more current than the decoder can handle. With no load, running slowly, it might be OK for a short time. Even at this low rate, the enemy is heat. Eventually even this borderline overload will burn out the decoder. As the loco runs faster or starts to pull cars, or goes up a hill, it needs even more current and you’re even more likely to fry the decoder.
Look at the outside of the decoder. If you see a small black pimple that looks like it’s burned a hole through the outer plastic layer, that’s a pretty good indication that something fried.
But y’know, sometimes it’s just a loose wire, and all you have to do is fix it to bring everything back to life. I had an engine that was flakey like that, and I ended up just pulling the decoder out and re-seating it in its plug. It ran fine after that.
Thanks for the replies. I dont have a layout complete so I was just running the locomotive back and forth on about 12’ of pretty straight track. However after looking at the trucks part of the metal that goes up to the red wire , from the trucks can pivot and touch the frame. I dont think the decoder ever got hot and I have never smelled anything. I think I will do what spacemouse suggested and hook the black and red wires to the rail and see what happens.
How can I isolate the trucks from the frame because if it didnt cause a problem ,I can see where it could. I kinda suspect my black wire to the frame may not have had a good enouh bare spot when I connected it. So maybe I just have a bad connection on the black wire. I did pop the body off and everything looks fine. I am still at work but will do more checking tonight.
You probably can’t isolate the trucks from the frame very easily. In fact, on some of these engines, the only way to get the power off of one side is to use the frame as your conductor. What you can (and must) do, though, is isolate the motor from the frame. To save on wiring, many older locomotives were designed with a metal frame and a metal engine housing, and that housing was part of the electrical circuit. What you have to do is remove the motor from the frame, insulate it with piece of electrical tape, and replace the motor using a nylon screw instead of the metal screw you took out. Betcha it’s a 2-56 screw. Then you can attach the motor lead to the motor frame, and the power lead to the power frame.
The black wire that i soldered to the frame must have not been making good connection. I took that wire off and resoldiered it read the adress from the program track, moved it back to main and every thing worked fine. Now I got to make sure that truck is isolated somehow. Maybe I need to get some pictures. MisterBeasley, this must be not as old a loco as you are thiking. The mototr has the metal clip on the bottom. I had clip the metal prongs and put electrical tape between the fram and the motor. If I could find a newer loco to but m old orange and white ICG body on I would do that rather than loose a decoder. Sorry I dont know the model of the train. I collected most of my stuff 15 years ago lost interest as I have too many hobbys. I also do 3d computer rendering and animation for an architect, am a pro bass player and restore military jeeps!! too many hobbies! But with 3 little kids we are just now getting back into the trains.
“Long, long time ago, I can still remember, how that music used to make me smile…”
I played guitar in a couple of college bands back in the '60’s, but was never good enough to go any further. Now, my little girl’s fingers dance across the frets of that '65 Fender Jaguar.
Glad to hear your problem wasn’t a french-fried decoder. Toot the whistle a few times for me, OK?
me to!! I sure thought it was gone but after looking at the truck on that ole athearn and another I dont know if they are worth the risk. Both of the older ones have metal pickups that can touch the frame I just play at a Variety show nothing big but its good extra money for my hobbys and I love playing also. So hard to beat making good money doing something you would do for free I bet that ole Fender is worth alot now days.
Any ideas about isolating the trucks or is it a worthless cause?
It’s pretty much a lost cause to isolate the frame of an Athearn. Just isolate the motor. Between cutting off the lower prong on the bottom brush clip (the piece that touches the frame) and putting in a layer of insualting tape, that pretty much takes care of it. You cna get more reliable pickup by soldering wires tot he metal truck dieframes ont he side that ends up contacting the chassis, but that just bypasses the potentially troublesome friction connection at the bolster and gives a more reliable method of getting the power from that side intot he decoder. The frame will still be ‘hot’ but so long as the motor is isolate, you’ll be fine.
Technically, only the motor BRUSHES have to be isolated, at least in a standard permag motor. So a metal framed motor, screwed to a metal chassis, the has one side live to one of the rails, is fine so long as neither brush contacts teh metal frame of the motor - plastic end cap, os some other insulating method. A lot of older motors have one of the brushes soldered to the motor case. Eliminate that and the motor may indeed be isolated for DCC use.
Thats interesting. I assumed that if the truck metal which is attached to the red wire could turn and touch the frame that is attached to the black wire I would fry my decoder. The decoder is getting pretty warm. I can feel the heat of it thru the top of the body. And I am still just running it back and forth on a section of straight track.
If the black and red touch, that’s just a short. What fries the decoder is if the black touches the orange or gray, or the red touches the orange or gray. If the motor is isolated from the frame,a nd the truck gets turns sideways (not easy if the drive shaft is hooked up) and manages to touch the truck side plate fromt he red wire side to the frame, it will just short out the track power.
The problem you might be referring to is with the Proto2000 Alco S1. Those have the trucks isolated fromt he frame, but one side of the motor is grounded to the frame. On that loco, if the truck derails it’s fairly easy for it to turn far enough so that one of the wheels contacts the frame - this puts the red or black in contact with the orange, frying the decoder. The fix there is to again isolate the motor from the frame, now you have both the motor and the trucks isolated from the frame.
Bottom line - one rail grounded to the frame - ok as long as the motor is insulated from the frame. Trucks isolated but motor grounded to the frame - not so good because a derailment can put a wheel against the fram, connecting the input and output of the decoder.
As for the DSD100LC getting warm - the Athearn motor is probbaly at ornear the limit of that decoder. i think it’s only rated for about 0.8 amp continuous load, and the old Athearn motors are near that. Also make sure you used the proper speaker - you need an 8 ohm speaker. If you connected two speakers in parallel, you only have a 4 ohm load and will overheat and damage the amplifier. And you did put the included capacitor in series with the speaker, right? This filters out the frequencies too low to be reproduced by the small speaker, skipping this just makes the amplifier work harder (and get warmer) all for the sake of worse sound quality.
I just play at a Variety show nothing big but its good extra money for my hobbys and I love playing also. So hard to beat making good money doing something you would do for free 
I bet that ole Fender is worth alot now days.