The New Atlas RS-3s Decoder Installation and Shell Swapping

[rickb773]

I’ve been working to get enough DCC engines to resume operations on my Pennsylvania-Reading Seashore Lines layout. I previously purchased some of the new Atlas GP7/9s and swapped some old favorite Atlas shells onto them so that I didn’t have to solder DCC decoders onto the older frames. [I have aged out of soldering.] I purchased ESU decoders for the new Atlas silver series engines. (I am not a fan of diesel sound so this saves me $40 per engine.)

When Atlas announced (years ago) their new RS3s, I was hopeing I could use my old Reading RS3 shells on them. I purchased 5 silver series RS3s and ESU 59925 decoders. Two will remain as Pennsy units and the other 3 were planned to receive the old Reading RS3 shells. [In the early 1950s, Reading usually won the coal contract for the electric power plants in New Jersey and since it shared PRSL ownership (with the Pennsy) it had trackage rights. The coal drag was almost always heading by a trio of green Reading RS3s.]


The old RS3 chassis (2 types)

After testing all the new engines on DC, I opened them up by removing the 2 very tiny screws holding the board in place.





I was surprised to see the DC plug was held in place by a wide tight rubber band which adamantly refused to slide off. I have no idea why it was there. Eventually I slid a small screw driver under it which enabled me to safely slice it off with an X-Acto knife.



I removed the DC plug and then plugged in the 24 pin decoder (always a fun job). I screwed the board back on the frame and placed it on the track to make sure it would run under the DCC default address 0003.





Now it was time to fit the old shells on the new chassis. One of the “newer old” RS3 shells (with attached running boards and attached couplers) snapped right into place. The “older old” RS3 shells (with separate handrails and Kadee knuckle coupler modifications) proved more difficult.

First, I had to unscrew one of the coupler pockets to slide the shell onto the new chassis. Then just when I thought I was home free, it snagged on the cab and would not snap into place. It lined up perfectly but would not seat fully. I traced it to a couple of protrusions at the top of the interior cab assembly which were hitting the top of the light board. Cutting the tabs down with a knife solved the problem and allowed the shell to seat fully.

The only other issue I had was the “newer old” shell was a custom paint job and the headlight light was radiating through the top of the shell near the fan. I’ll have to add a piece of tape to the underside to solve that.

Now, at the risk of Peteski mocking me again, I need to take them to get programmed (road #s) as 2 sets with each set having one unit designated running in reverse. [In the early 1950s, most diesels were designated as running long hood forward. Probably because that was the way steam engines ran (and engine crew safety at crossings).]

[peteski]

Now, at the risk of Peteski mocking me again, I need to take them to get programmed (road #s) as 2 sets with each set having one unit designated running in reverse.

Thanks for the write-up. Interesting to see how Atlas reworked the mechanism to shoehorn the sound decoder capability.

Mocking?  Really?
I seem to recall that I was trying my best to help troubleshooting that strange issue (which I believe was partially self-inflicted), but you were very frustrated, not willing to cooperate, and putting ESU decoders down. Oh well, I'll not try to help again. 

[jjb62556]

Sounds like the later Atlas Classic shells worked just fine. The older Atlas/Kato shells are the problem shells .

[thomasjmdavis]

Sounds like the later Atlas Classic shells worked just fine. The older Atlas/Kato shells are the problem shells .

I don't know if this will work with RS-2s, but with RS-1s, I found I could combine Atlas/Kato hoods and cabs with Atlas/China walkways and underframes (the clips that hold things together even line up), and in that configuration, would fit on an Atlas/China chassis.

[OldEastRR]

When I acquired  second-run RS3 I too found the first-run shells wouldn't interchange. The frame is different-shaped. I wanted a DCC loco and the first run wasn't. It took a bit of work but I got the custom-painted shell onto the first unit and sold the other engine. I don't remember the second run shell having any trouble fitting on the first run frame.
I'm debating on getting one of the new Atlas ones, as the NH had plenty used for commuters-- except I can't use the post 1955 paint scheme. I'd have to repaint it (and add a steam generator and ATC box), but the green-orange scheme is much easier to do than the green-multi-stripe pain in the @#$@ one is.
However, I'm waiting to hear how these things run before I buy, as I'm less than thrilled by their FA1.

What type decoder designation do they take?

[peteski]

What type decoder designation do they take?

Decoders with E24 connector.  It is shown in Rick's photos.

[reinhardtjh]

I think it's going to be interesting when my Gold versions arrive and I see how much space in the nose is actually taken up since I want to convert mine to a chop nose RS-3m that the D&H made.  I may have to remove the whole PC board and hard wire a Nano which means getting a Gold was a waste.  I think this is the same issue @randgust faced with the new GP-7 model.

The intended result:

[OldEastRR]

Decoders with E24 connector.  It is shown in Rick's photos.

I wonder if more than one or two decoder makers are going to start producing these new-age plug-in units. Gone are the days when there were 5 or 6 companies to choose from. Has the era of drop-in decoders ended? (at least for any locos produced from now on)

[thomasjmdavis]

I wonder if more than one or two decoder makers are going to start producing these new-age plug-in units. Gone are the days when there were 5 or 6 companies to choose from. Has the era of drop-in decoders ended? (at least for any locos produced from now on)

I, for one, hope that the era of the drop in decoder has ended- provided that manufacturers agree on standardizing one plug configuration for N.  Having decoders that are interchangeable in a fleet of locomotives, instead of having one "drop in" for your IM F units, another for Kato F units, another for MTL FTs, another for Atlas GP-7/9's, etc. etc., would allow for the modeler to standardize on their favorite decoder, instead of opting for whatever decoder that fits and is available at a given time.  And, as time goes on, upgrades become simple, and if the decoder blows in a loco that is 20 years old, you won't be searching eBay in hopes of finding the drop in that no one has made for the past 10 years.

[peteski]

I wonder if more than one or two decoder makers are going to start producing these new-age plug-in units. Gone are the days when there were 5 or 6 companies to choose from. Has the era of drop-in decoders ended? (at least for any locos produced from now on)

No need to wonder. Digitrax already joined the E24 bandwagon (that decoder was mentioned in the DCC/electronics section of the forum. I'm sure others will also do the same.  E24 is relatively new interface - it will take some time to get adopted by others.  Atlas however seems to waffle between using E24 and Next18, so nothing seems like s permanent choice.

I think it's going to be interesting when my Gold versions arrive and I see how much space in the nose is actually taken up since I want to convert mine to a chop nose RS-3m that the D&H made.  I may have to remove the whole PC board and hard wire a Nano

Looking at the photos, the speaker is in the nose, so you might be able to keep the existing PC board and just chop off the speaker end, then relocate the speaker (to the fuel tank maybe?).

[wm3798]

So... about those old DC drives....

[reinhardtjh]

Looking at the photos, the speaker is in the nose, so you might be able to keep the existing PC board and just chop off the speaker end, then relocate the speaker (to the fuel tank maybe?).

You're right!  I had assumed the front was to the right in the picture (because of the shell in the background?), but it's not.  I see the blocks on the frame where the cab goes.  Looks like the nose starts just to the left of the last white JST connector.  I think that will take a bit of surgery.  I wonder when the Gold units will make it to the distributors (and what Atlas had to do to them to make them presentable that didn't have to be done with the Silver).

[spookshow]

If it's any measuring stick, recent gold releases (B23-7 and U23B) came in a couple of weeks after the silver.

-Mark

[GM50 4164]

is this the first unit from Atlas to have a small can motor like Bachmann has been using in their switchers and other units? Looks to be quite a bit different than what they usually put in these units.

@reinhardtjh , if I'm undertanding your post correctly, there shouldn't be any difference between the silver and gold versions that I'm aware of.

[peteski]

is this the first unit from Atlas to have a small can motor like Bachmann has been using in their switchers and other units? Looks to be quite a bit different than what they usually put in these units.

From what little I can see, it looks like a small conventional iron-armature "can type" motor, but not a coreless motor that Bachmann uses on several of their new-ish N scale locos.  Seems like another sign of Atlas moving away from the Kato-like mechanism design.