DCC into older Atlas RS (1,2,3...)

[r.cprmier]

Recently, I acquired a "vintage" Atlas S-1, and am in the midst of trying to install a decoder into it.  Realizing that trying to stuff a Tsunami into her innerds would be like trying to fly without a guy wire, I opted for a plain-Jane decoder.  Welllllllllllllllllllllllll-l-l-l-l-l-l-l-, it is hard to do!  I am winding up thinking that I just might junk the top weight, make a couple of retainers for the flywheels, and then try to put the shole shee-bang back together.  So far, I have tried a NCE DA-SR, and an NCE D13SRP to no avail.  I have learned a couple of new words along the way, though...
Has someone done this successfully; and if so, can they offer me some input as to what magic words they used.  Mine don't work real good...

Rich

[FFJOHNL312]

Rich:
Your header says it is an RS, but your text says it is an S series. Which is it?

For the RS series, IF the unit has a Kato drive and a circuit board, it should be easy to replace the factory circuit board with an NCE DASR. If it is an older circuit board (Roco drive) that has copper traces on it, cutting the traces and soldering a decoder on may be the better choice.

For the S series, NCE makes the ATL-S4 which is a direct circuit board replacement.

If you can send me pix, I will be able to guide you through this.

Also, check out Tony's Train Exchange website in his installation gallery of pictures.

John Loesch

[barrowsr]

Tony's might recommend an N-scale decoder.  They are a lot easier to fit in cramped spaces.

Robin

[Jim Banner]

Rich, I recently put Digitrax DZ123 decoders in a couple of Atlas/Roco S-2 locomotives, which are the same as the Atlas/Roco S-1.  If yours says ROCO on the bottom of the frame, then it is the Roco mechanism.  I have photos of the installation including the all important isolation of the bottom brush holder.   

John's suggestion is also a good one.  The decoders are very similar except the ATL-S4 has-stop-on-dc; the DZ-123 has transponding.  The price of the DZ-123 is half that of the ATL-S4, I assume because the DZ-123 is a general purpose decoder used in many locomotives in Z, N, H0 and other scales while the ATL-S4 has a very limited market.

Whichever way you choose to go, be sure that the directions include isolating the bottom brush holder of the motor.  If this step is neglected, the locomotive will still operate well, at least until the locomotive derails and destroys the decoder.

[r.cprmier]

FF John;
It is an S-1.  I don't believe that there would be any dimencional difference in either long hood, as they are interchangable.  Where the problem seems to be is that the DA-SR jams against the inside of the hood as I push it down, causing the bottom to flare out; this is why I tried the smaller decoder.  It is a first for me, as I hadn't previously attempted to do an engine that wasn't in some way or another, DCC ready.  Unless I maybe mill down or replace the top moulded portion of the assembly.
The engine doesn't say "Roco" on the bottom, but does indicate it was made in Austria, possibly making either ROCO or MEHANO the jobber.   Yep, it is a challenge.  Like I said, I'll get it because I will; one way or another.  I hate defeat.  Any help will be appreciated.   (Hmmm, I  wonder of Hunt ever asked for help here...)

Rich

Rich

[Jim Banner]

_{Of all the things I've lost in life, I miss my mind the most.}

I just checked, and mine says "Made in Austria" too.  That makes it Roco.  (Mehano is Solvanian.)

[FFJOHNL312]

Ok,  Jim,so fill me in here. As I have not had to deal with one of these Roco drives specifically, we are talking a circuit board with copper traces on it?
John

[Jim Banner]

Yes.  It runs the length of the locomotive and is the most prominent feature in the photo below:



The red arrow points to the Digitrax DZ123 decoder (also red.)

[FFJOHNL312]

Ok. I dig it. I did an older Atlas/Roco GP40, the same principles apply.

John

[r.cprmier]

I wound up taking the stock board out, and just direct wiring the leads to the respective connections.  as to the bottom bolt, I simply put a piece of electrical tape on the frame, thus insulating the terminal from the body, and a possible short circuit/death of a decoder. 
The problem I am incurring is that I cannot seem to fit everything I need into the hood space.  If someone writes and tells me they have installed a sound unit, I will never believe them!
I am going to go back into the unit when I have time, and just re-do everything, saving the "surgury as a last result.

Rich

[Jim Banner]

Only problem, Rich, is that the bottom brush holder is connected to the motor frame.  If you leave the motor frame connected to the locomotive frame, all the tape in the world under the brush holder will not save the decoder from a smokey death.

[FFJOHNL312]

Rich:
Hate to tell you, but some folks out there HAVE installed a sound unit in their Atlas S units. Most recently was covered in Model Railroader a while back, I believe a Soundtraxx DSD-090 was used and the speaker went in underneath the radiator fan on the top of the long hood.

Do not despair, you will get this bugger done. Even the best of us have fried a decoder now and then--some of us more so than others!