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Well-Known Member
I recently picked up a pair of Soundtraxx Econami series ECO-21PNEM decoders to install in a couple Fox Valley GP-60M's. I already had two of the same locomotives with their full Tsunami decoders that I installed, so I was curious to see how close their ECO's were and whether the cost savings was worth it or not. These are the 21-pin interface, and the speaker connects to a JST-type plug on the main board (not the decoder). Incidentally, Fox Valley uses Bowser circuit boards on these locomotives.

One ECO works great, even consists perfectly with the TSU-equipped locos straight out of the box.

The other does everything except produce sound. Programmed new address, runs forward & reverse fine, lights work. But no sound. First I thought it was a bad speaker-- plugged the speaker into another loco, works fine there, so not that. Then I thought it was the board. Pulled a TSU off one loco, installed it on this one, works fine with sound. Tried the ECO in question on another locomotive, same result, all functions except sound. I've tried:

-making sure it's not muted
-making sure the master volume is not set to zero
-full decoder reset (CV 8)

Anyone have any other ideas? My next step is to send it back to Soundtraxx under warranty, but I wanted to make sure I'm not missing anything else before I do so.
Thanks all.


Well-Known Member
Staff member
Talk to Soundtraxx first, they may be able to give you a fix. I know the 1st Gen Soundtraxx decoders had a decoder recovery program that went deeper into a decoder than just resetting via F8=8. If you are using NCE it also has one under option 7. That goes right through every CV, resetting each one in sequence.


Well-Known Member
Yeah, sounds defective to me. I'd echo Toot, though, and say to call Soundtraxx first to see what they say.

Personally, I own two decoders of the ECO line and love them.


Well-Known Member
Thanks all, I spoke to Soundtraxx and they couldn't think of anything else either, so the decoder went in the mail to them last week. I'll report back if anything of interest comes out of it.


Well-Known Member
Well I'm pleased to report that I received the decoder back from warranty repair, and it now works fine. Kudos to Soundtraxx as their service turnaround was pretty quick--I think about a week from the time I sent it off, until return. The paperwork included, however, doesn't indicate what exactly was wrong, just that it was repaired. Without any additional information to pass along, and now that the set all have working decoders, I'll share a picture instead.

Here's all four GP-60M's in service with an intermodal on the upper loop. Down below, an SP SD9 passes with a lumber train (yes, that's the new P2K SD9).


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