Bachmann DCC decoder

[Catt]

Have one of those "rare" birds a very good running N scale GE 70 ton loco with DCC. I have been looking for a replacement decoder (drop in hopefully) but so far no luck.Does anyone know if there is such a critter?And by who?

[peteski]

Well, I made bunch (about a dozen) of circuit boards for the 44-tonner to retrofit Digitrax DZ125(6) decoder into them. But that project (as usual with me) got sidetracked.  If 70-tonner uses the same decoder as the 44-tonner then my retrofit would also fit that loco. 

[Catt]

Pete,
I don't have a clue as to what is under the hood of this little beast.It runs to good to go snooping around in there (it would be my luck that I would screw it up).Maybe one of the other guys will know and chime in.

I'm not faulting the Bachmann set up as it does what I want,but I would like a back up plan for the day it might decide not to play nice anymore. 

[peteski]

If and when the Bachmann decoder decides to die, you can always just hardwire one of the several small decoders available from Digitrax, TCS, Lenz or few others.  The install won't be as clean as a replacement circuit board, you it will be functional.

[reinhardtjh]

Have one of those "rare" birds a very good running N scale GE 70 ton loco with DCC. I have been looking for a replacement decoder (drop in hopefully) but so far no luck.Does anyone know if there is such a critter?And by who?

No drop in decoders, but both Digitrax and TCS have Z-scale decoders which are close.  The TCS MZA4 (scroll down) and the Digitrax DZ123M0 fit the Bachmann chassis width and include the LEDs front and back for lighting without having to add your own SMD LED.  They are also 4 function decoders incase you want to add some other lighting effect.

They are not the cheapest decoders you can use, but they are the closest to "drop-in" that are available.  The other option is to use Peteski's board or hard wire a TCS Z2, or other small decoder (Zimo, CTK, Digitrax DZ126, etc) and LED with resistors.

Examples:
Bachmann GE 70 tonner decoder swap - NScale.net
Bachmann Spectrum GE 44 tonner - Trainboard

Well, I made bunch (about a dozen) of circuit boards for the 44-tonner to retrofit Digitrax DZ125(6) decoder into them. But that project (as usual with me) got sidetracked.  If 70-tonner uses the same decoder as the 44-tonner then my retrofit would also fit that loco. 

The 70-tonner chassis is very similar to the 44-tonner.  It's just a little longer.  I'm pretty sure your circuit board would work in the 70-tonner as well.

[Catt]

Thanks for the input guys.I hoping for a non solder conversion as my hands keep me from holding onto a soldering iron for very long.So far my NCE system is doing a great job with this little buggar but I figured it would be a good idea to come up with an alternative to the stock decoder just incase.

[peteski]

Well, there is always the option of either buying a direct replacement decoder board from Bachmann or sending it to Bachmann for their famous lifetime warranty repair service.  The last option is labor-free (on your part).

For all we know that decoder will never fail you anyway, 

[Catt]

If and when it goes it will be replaced by a Digi Trax or NCE decoder.But until it goes I ain't messing with it. Pete what would one of your boards cost me?

[peteski]

Catt,
more info about the 44-tonner adapter board is in https://www.therailwire.net/forum/index.php?topic=32605 .
I haven't really seriously thought about the price. It was suggested that up to a $50 plus shipping would be acceptable for the fully populated adapter retrofit (the circuit board with the Digitrax DZ125, couple of warm white LEDs and coupe of resistors).   A blank adapter board would be less expensive of course.

But before sell one for the 70-tonner, I would need to make sure it will fit in it (as the adapter plus a decoder is thicker than the Bachmann decoder.  The 44-tonner has slightly sloping hoods (which allows the decoder to fit). I'm not sure about the fit in the 70-tonner.