Trains.com

Subscriber & Member Login

Login, or register today to interact in our online community, comment on articles, receive our newsletter, manage your account online and more!

Decoder recommendation for RS3 Diesel

3024 views
27 replies
1 rating 2 rating 3 rating 4 rating 5 rating
  • Member since
    January 2014
  • 197 posts
Decoder recommendation for RS3 Diesel
Posted by ChrisVA on Sunday, August 13, 2023 3:39 PM

I have a DC powered RS3 diesel that I want to convert to DCC. What would be a good decoder to use that would have prototype sounds? Thanks in advance.

  • Member since
    December 2004
  • From: Bedford, MA, USA
  • 21,483 posts
Posted by MisterBeasley on Sunday, August 13, 2023 4:39 PM

I have a Proto 1000 RSC3 Diesel in Milwaukee colors.  An RSC3 has six-axle trucks, designed for running on lighter-duty lines.  I think I have an old Soundtraxx decoder in it.  I get the classic Alco sound out of it.  I can almost smell it burning oil.

What make of HO locomotive do you have?  My decoder required hard wiring and installing a speaker, but it was an easy job.  There was plenty of room inside.

It takes an iron man to play with a toy iron horse. 

  • Member since
    January 2014
  • 197 posts
Posted by ChrisVA on Sunday, August 13, 2023 4:42 PM

This is an old Tenshodo RS3 I got off of eBay, so it does not have any provisions for DCC. It would be a custom install.

-C

 

Moderator
  • Member since
    June 2003
  • From: Northeast OH
  • 17,249 posts
Posted by tstage on Sunday, August 13, 2023 5:11 PM

I have an ESU Select in a newer Atlas RS-3.  The low speed and sound is just terrific.  Just make sure to isolate the motor brushes from the frame before installing any decoder in your Tenshodo.

For speakers I would hightly recommend Scale Sound Systems.  JT is a sound engineer by trade and designs & 3D prints his own baffles for his speakers.

Tom

https://tstage9.wixsite.com/nyc-modeling

Time...It marches on...without ever turning around to see if anyone is even keeping in step.

  • Member since
    May 2021
  • From: Northern Colorado
  • 86 posts
Posted by CharlieM on Sunday, August 13, 2023 5:29 PM

ChrisVA

I have a DC powered RS3 diesel that I want to convert to DCC. What would be a good decoder to use that would have prototype sounds? Thanks in advance.

I just converted an old Atlas yellow box RS3 (with Kato drive) to DCC. I used a Tsunami TSU-PNP8 (Alco) and TDS Supersonic Small 18x13mm speaker+enclosure from Tony's. It was an effort but it works very well. Tsunamis  are my favored decoders. It took some plastic hacking to get the speaker in but the suger cube speaker is really amazing.

The TSU-PNP8 may not fit the Tenshodo so you may have to go with the pigtail version of the TSU2 but it would still be my choice.

Charlie - Northern Colorado

  • Member since
    May 2020
  • 1,057 posts
Posted by wrench567 on Sunday, August 13, 2023 8:10 PM

   Is this a brass locomotive? Could you post pictures of the drive system?

       Pete.

  • Member since
    January 2014
  • 197 posts
Posted by ChrisVA on Monday, August 14, 2023 4:13 AM

It is a brass locomotive. I'll try go get a picture with the shell off to show what I am dealing with.  As for prototypical sound, (I'm not a prototype expert) it sounds like I would want a decoder with ALCO sound.  

Possible decoders would include: 

Soundtrax TSU-AT1000 with the Alco 244 sound files.

Tsunami TSU-PNP8

  • Member since
    May 2021
  • From: Northern Colorado
  • 86 posts
Posted by CharlieM on Monday, August 14, 2023 7:57 AM

The TSU-1000AT may be a discontinued model and it was a 1 amp version. With your older, and probably higher current, motor you will probably need the 2 amp capability of the TSU-2200. Be sure to measure your motor stall current before you buy. The TSU-2200 is available in an Alco version.

Charlie - Northern Colorado

  • Member since
    January 2014
  • 197 posts
Posted by ChrisVA on Monday, August 14, 2023 8:32 AM

Hopefully these image links work to give an idea. Actually it's an Alco brass model, not a Tenshodo.

There is very little space between top of motor and the shell.

 

 

 

 

  • Member since
    May 2021
  • From: Northern Colorado
  • 86 posts
Posted by CharlieM on Monday, August 14, 2023 9:44 AM

A few comments:

It looks like there might be space for a TSU-2200 on the sides next to the drive shafts but keeping wires confined will be a challenge.

Isolating the motor connections will be easy but I'm not sure about the track pickups. Not clear if they are both isolated from the frame.

That motor looks like a current hog. Be sure to measure the stall current.

Charlie - Northern Colorado

Moderator
  • Member since
    June 2003
  • From: Northeast OH
  • 17,249 posts
Posted by tstage on Monday, August 14, 2023 10:53 AM

CharlieM
That motor looks like a current hog. Be sure to measure the stall current.

I would even consider swapping it out for a flat can motor with dual motor shafts.  That has two advantanges:

  1. Lower current draw from the motor
  2. More overhead room for mounting the speaker/baffle and decoder

Remove the old motor and create a platform out of styrene sheeting for the new can motor so that the motor shafts are concentric to the gear train axles.  I would also look for a motor that has long motor shafts to reduce the gap between the two.

And while the silicone tubing does work, you might also want to think about a NWSL universal joint kit that matches the diameter of the motor shaft you have/will be getting.  You can also add that later, if you'd like.

Lastly, are you considering adding lighting to the front & rear headlamps?

And how are the gears on your RS-3?  Alco Models diesels are usually notoriously loud.

Tom

https://tstage9.wixsite.com/nyc-modeling

Time...It marches on...without ever turning around to see if anyone is even keeping in step.

  • Member since
    January 2014
  • 197 posts
Posted by ChrisVA on Monday, August 14, 2023 11:28 AM

Thanks for all of the advice. I'm going to look for a flat can motor with dual shaft. This one from Micromark looks pretty decent:

https://www.micromark.com/Flat-Can-Motor-Style-2025-12v

 

The gears are indeed pretty loud. I'm not sure what I can do about that. It was screeching when I first got it and I lubricated it. Now it runs more quietly but still louder than modern models. 

I was thinking of adding the front and rear headlamps. I was thinking of using mounted LEDs for those. I'll have to look at some RS3 pictures to see where they go exacly. Not obvious from looking  at the shell. Looks like I'd have to drill some holes where they are supposed to go.

 

  • Member since
    March 2011
  • 1,950 posts
Posted by NVSRR on Monday, August 14, 2023 11:47 AM

The alco sound you want is of the 244 power plant.  I would say use scale sound speakers.  You can get them I. Small sizes plus they currently are the best sound reproduction.   Sugar cubes  are a close second like those from Tony's train exchange.  Tsu, soundtraxx, and Esu loksound are all good decoders.    Spac could be your determination of exactly which one you get based on overall physical size

shane

A pessimist sees a dark tunnel

An optimist sees the light at the end of the tunnel

A realist sees a frieght train

An engineer sees three idiots standing on the tracks stairing blankly in space

  • Member since
    February 2002
  • From: Mpls/St.Paul
  • 13,892 posts
Posted by wjstix on Monday, August 14, 2023 1:35 PM

I used one of the Micro-Mark can motors to repower an old LL Proto 2-8-8-2 (naturally I got one from the one batch that had motors with a defect) and it worked out well. I think it would be a good choice for your engine.

Stix
Moderator
  • Member since
    June 2003
  • From: Northeast OH
  • 17,249 posts
Posted by tstage on Monday, August 14, 2023 9:28 PM

ChrisVA
I was thinking of adding the front and rear headlamps. I was thinking of using mounted LEDs for those. I'll have to look at some RS3 pictures to see where they go exacly. Not obvious from looking at the shell. Looks like I'd have to drill some holes where they are supposed to go.

Chris,

For all my brass locomotive headlamp installs, I've gone with surface mount (SMD) LEDs - specificially 0603s, which are 0.06 x 0.03".  For wiring I chose insulated 34 AWG magnet wire because of its small size.  It allows me to pass 2 wires - side by side - through a single #80 hole.

Here are 0603s installed in the front & rear headlamps of an Alco Models 0-10-0 brass switcher.  You could even use 0402s if you wanted to go smaller: (Click photo to enlarge)

To secure the LEDs in place I use Testors Clear Parts Cement.  It dries clear, holds well, stays relativlely flexible, and insulates the rear of the LED from shorting to the brass headlamp.  And, should I ever need to replace the LED, I can peel the cement out of the headlamp with a pair of tweezers without marring the interior of the headlamp.

The only other thing I do is paint 1 or 2 layers of thinned Tamiya X-26 Clear Orange on the LED to give it a slight yellowish hue to replicate an incandescent bulb.  Oh, and I use a much higher value resistor (10K) to soften the intensity of the beam.

Tom

https://tstage9.wixsite.com/nyc-modeling

Time...It marches on...without ever turning around to see if anyone is even keeping in step.

  • Member since
    September 2002
  • From: Maricopa, AZ
  • 269 posts
Posted by DanRaitz on Tuesday, August 15, 2023 9:37 AM

tstage
Remove the old motor and create a platform out of styrene sheeting for the new can motor so that the motor shafts are concentric to the gear train axles.

 

If you go this route, you'll find that the old motor filled up most of the fuel tank.  What I have done when I've replaced this motor is to fill the fuel tank with layers of sheet lead to where the motor shafts line up with the worm gears in the truck towers.  By using lead instead of building a styrene mount what you're doing is adding weight to the locomotive. Thumbs Up

 

Dan

 

If women don't find you handsome, they should at least find you handy .... Red Green
Moderator
  • Member since
    June 2003
  • From: Northeast OH
  • 17,249 posts
Posted by tstage on Tuesday, August 15, 2023 10:18 AM

Thanks, Dan.  I presumed that the motor was flush with the chassis floor.

Agree on the lead sheeting.  Good info for the OP to know.

Tom

https://tstage9.wixsite.com/nyc-modeling

Time...It marches on...without ever turning around to see if anyone is even keeping in step.

  • Member since
    January 2014
  • 197 posts
Posted by ChrisVA on Tuesday, August 15, 2023 10:36 AM

Great recommendation RE: lead sheeting. I'll look into that.

Chris

 

  • Member since
    May 2020
  • 1,057 posts
Posted by wrench567 on Tuesday, August 15, 2023 1:39 PM

  Are the couplers mounted in a plastic box? If not then they will be hot to the chassis.

  My last sound instal was an Atlas/ Kato RSD4/5. I used a Loksound V5 on the Atlas style board. Not wanting to cut weight out, I used a cab roof mount speaker from Streamline Backshop. Works and sounds great.

      Pete.

  • Member since
    September 2014
  • From: 10,430’ (3,179 m)
  • 2,311 posts
Posted by jjdamnit on Tuesday, August 15, 2023 6:24 PM

"Uhh...I didn’t know it was 'impossible' I just made it work...sorry"

  • Member since
    September 2014
  • From: 10,430’ (3,179 m)
  • 2,311 posts
Posted by jjdamnit on Thursday, August 17, 2023 12:19 PM

Hello All,

Recently I have been upgrading my non-sound decoders to sound.

The latest version of the SDXH167D sound decoder apparently has better speakers than the previous units.

Also, it comes factory loaded with the ALCO RS1 prime mover and horn sounds. 
Mountain Subdivision Hobbies has them for $47.97 (+S/H).


I definitely recommend re-motoring.

With DCC the need for flywheels is not as great for smooth running, which leaves more space under the shell for a decoder and speaker.

A-Line/Arrow Hobby offers many options to replace the tube driveline with plastic or metal driveshafts and couplers.

Measure the diameter of the drive shafts from the gear towers to find the couplers that best fit your situation.


I found a digital caliper at Harbor Freight that measures both standard (SAE) and metric. The SAE measurements can be read in both digital and fractional formats. 
Looking at the photos you posted it appears that the trucks are isolated from the frame with those red fiber washers.

Not knowing if the frame is an electrical path might make isolating the motor/trucks more challenging.

It seems I can't type beyond this...

"Uhh...I didn’t know it was 'impossible' I just made it work...sorry"

  • Member since
    January 2014
  • 197 posts
Posted by ChrisVA on Thursday, August 17, 2023 12:29 PM

Test post. I am trying to post some replies but I keep getting a 403 error. Anyone else encountering this?

 

  • Member since
    September 2014
  • From: 10,430’ (3,179 m)
  • 2,311 posts
Posted by jjdamnit on Thursday, August 17, 2023 12:32 PM

Hello All,

Yes, I keep getting the same error if I post over 190 words?

Hope this helps.

"Uhh...I didn’t know it was 'impossible' I just made it work...sorry"

  • Member since
    January 2014
  • 197 posts
Posted by ChrisVA on Thursday, August 17, 2023 12:34 PM

An update on this. It turns out I had a Soundtraxx Econami ECO-PNP diesel decoder from when I did some Stewart loco converstions. I was able to use lead sheet weights to get the motor at the same level as the gear shafts and use silicon tubing to connect to the gear shafts.

Current idea is to use the ECO-PNP decoder and mount it on a strip of Evergren styrene and mount that on top of the flat motor using silicon sealant. 

Question: how to mount the decoder to the strip of styrene? This is a plan PCB with no protective wrapping. I have seen other threads that mention using Gorilla clear mounting tape.  I'm concerned the tape or whatever adhesive I use in damaging or shorting out the decoder.

Thanks!

 

 

 

  • Member since
    September 2014
  • From: 10,430’ (3,179 m)
  • 2,311 posts
Posted by jjdamnit on Thursday, August 17, 2023 12:34 PM

Hello All,

(Post Continued)

Using a multimeter, set to the continuity (beeper function, will help you "trace" the electrical path from the wheels to the wires attached to the top of the gear towers.

Another option would be to use Stanton-type, self-powered trucks.

These can be found a Northwest Short Line; HO Stanton Drives.

It's a more expensive option but it vastly simplifies converting to DCC as each truck is a self-contained unit drawing power directly from the decoder- -no need to upgrade the motor or drive line and eliminates the gear noise.

Keep us appraised of your progress, and as always...

Hope this helps.

"Uhh...I didn’t know it was 'impossible' I just made it work...sorry"

  • Member since
    January 2014
  • 197 posts
Posted by ChrisVA on Thursday, August 17, 2023 12:36 PM

Photos of current situation. Question is how to mount the decoder to the styrene strip?

 

 

 

Moderator
  • Member since
    June 2003
  • From: Northeast OH
  • 17,249 posts
Posted by tstage on Thursday, August 17, 2023 12:45 PM

Hi Chris,

It was probably me that recommended the Gorilla mounting tape.  It comes in a 3/4" wide roll, which you can cut to length.  And it has a rubbery silicone consistency with adhesive on both sides.  Holds very well and won't degrade.

Personally, I would skip the styrene strip and mount the decoder directly to the top of the flat motor housing using the Gorilla mounting tape.  It will also allow for better air circulation around the decoder.

Tom

https://tstage9.wixsite.com/nyc-modeling

Time...It marches on...without ever turning around to see if anyone is even keeping in step.

  • Member since
    September 2014
  • From: 10,430’ (3,179 m)
  • 2,311 posts
Posted by jjdamnit on Thursday, August 17, 2023 12:58 PM

Hello All,

Before figuring out how to attach your decoder of choice I strongly recommend replacing the plastic/rubber tube drive line with solid shafts and press-fit couplers available from A-Line/Arow Hobbies, Repowering Parts.

These kits have the option of metal or plastic drive shafts that you can cut to length.

The torque produced by the motor and the resistance of the gears might twist the plastic tube creating more problems.

remotor noise possibly from silicon tubing

Before mounting your decoder of choice I would pre-wire the decoder and solder the wires rather than using the unreliable slip-on connectors.

If you do decide to use the slip-on connectors I definitely recommend tinning the ends of the wires.

Have you identified the electrical path from the wheels to the screws on the gear towers?

Is the frame used as part of the electrical path to the old motor?

Not properly electrically isolating the motor will fry the decoder and possibly damage the new motor.

Have you considered mounting the decoder on the underside of the shell?

Since you are considering adding LED lights there would be wires from the decoder to the shell; White-F headlight, Yellow-R headlight & Blue-common.

Mounting the decoder to the inside of the shell there would still be wires running from the decoder to the gear towers (electrical path from the rails) and the motor; Red-Right Rail Pickup, Black-Left Rail Pickup, Orange-Motor Positive, Gray-Motor Negative.

Just a though.

Hope this helps.

"Uhh...I didn’t know it was 'impossible' I just made it work...sorry"

Subscriber & Member Login

Login, or register today to interact in our online community, comment on articles, receive our newsletter, manage your account online and more!

Users Online

Search the Community

ADVERTISEMENT
ADVERTISEMENT
ADVERTISEMENT
Model Railroader Newsletter See all
Sign up for our FREE e-newsletter and get model railroad news in your inbox!