Athearn FEF-3 MRC replacement decoder?

[dorniergp]

Hi Everyone,

I was able to buy an HO Athearn FEF-3 844 and it's really nice except for the MRC decoder.  It sounds horrible compared to my other locomotives.  I would like to replace the MRC decoder and was looking for the groups opinion.  Is there a drop in replacement or am I soldering in the replacement?  Is there a plug in the tender?  Are there any pictures of the tender open around?  I can't find any.

Thanks,

George

[bnsf971]

I don't think they have an 8 pin connector, there may be a 9 pin plug.
Tsunami Heavy Steam would be my first choice, though I have read good things about the WOW decoder. Nobody I know has one, so I haven't been able to form an experienced opinion on them.

[Paul Cutler III]

I did this for a fellow club member this year. He didn't care for sound, so I hardwired in a Digitrax DH123D. It runs so much better now.

As for how it's done, even with a sound decoder... Well, it's not simple nor easy. I ended up stripping out all the MRC wiring, including the headlights and numberboard lights. I only kept the wires between the tender and the boiler, and the circuit board in the tender that the plug attaches to.

Getting the tender open is a pain. It involves removing the tender load, removing the grabs, etc. Getting the boiler off is a major pain. There's a plug on top of the boiler near the cab that hides a screw. It's impossible to remove. I ended up drilling a hole through the bottom of the plug just big enough to get a phillips head screwdriver through it, and then I was able to remove the boiler top. Sheesh.

All the factory lighting was replaced with pre-wired surface mount LED's as I didn't trust the MRC ones. Both the owner of the FEF and myself thought that the bright green numberboard LED's looked terrible, so we just left them disconnected. The rear light was also a surface mount LED (it fit perfect with some Magic tape).

Figuring out which wires went where was the wiring challenge. Once we managed that, it was a snap to wire in the DH123. A Tsunami or QSI could be used instead, just wire in the MRC speakers (nothing wrong with them). There's plenty of room in the tender.

[dorniergp]

Hi and thanks for the reply.  Do you recall if there was a JST connector inside the tender?

Thanks,

George

Apr 20, 2014 11:02:13 GMT -8 Paul Cutler III said:

I did this for a fellow club member this year. He didn't care for sound, so I hardwired in a Digitrax DH123D. It runs so much better now.

As for how it's done, even with a sound decoder... Well, it's not simple nor easy. I ended up stripping out all the MRC wiring, including the headlights and numberboard lights. I only kept the wires between the tender and the boiler, and the circuit board in the tender that the plug attaches to.

Getting the tender open is a pain. It involves removing the tender load, removing the grabs, etc. Getting the boiler off is a major pain. There's a plug on top of the boiler near the cab that hides a screw. It's impossible to remove. I ended up drilling a hole through the bottom of the plug just big enough to get a phillips head screwdriver through it, and then I was able to remove the boiler top. Sheesh.

All the factory lighting was replaced with pre-wired surface mount LED's as I didn't trust the MRC ones. Both the owner of the FEF and myself thought that the bright green numberboard LED's looked terrible, so we just left them disconnected. The rear light was also a surface mount LED (it fit perfect with some Magic tape).

Figuring out which wires went where was the wiring challenge. Once we managed that, it was a snap to wire in the DH123. A Tsunami or QSI could be used instead, just wire in the MRC speakers (nothing wrong with them). There's plenty of room in the tender.

[bnsf971]

I agree with Paul, the best part of the MRC decoder is the speaker.

[Paul Cutler III]

There is no plug in the tender other than the one used to go to the boiler. If you want to put in a new decoder in an Athearn FEF w/ MRC Sound, you will have to solder in a replacement.

[dorniergp]

Apr 22, 2014 7:25:56 GMT -8 Paul Cutler III said:

There is no plug in the tender other than the one used to go to the boiler. If you want to put in a new decoder in an Athearn FEF w/ MRC Sound, you will have to solder in a replacement.

Thanks!