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Sound Decoders for Brass Steam Locomotives

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  • Member since
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  • From: North Carolina
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Sound Decoders for Brass Steam Locomotives
Posted by Aikidomaster on Wednesday, August 4, 2010 3:17 PM
I have several N&W brass steam locomotives. I want to add DCC decoders and sound. I am not what one would call an expert in the field of electronics, so I need something that is relatively simple to install. Obviously, good sound quality is a priority. What would you suggest? I have 2-8-0, 2-8-2. 4-8-4, and 2-6-6-4's.

Craig North Carolina

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Posted by WPAllen on Wednesday, August 4, 2010 4:27 PM

What motors are in the locomotives?  What type of tenders to they have such as square or Vanderbuilt? I'm in the process of doing a Western Pacific 2-8-0 with a small can motor and I can squeeze a Tsunami TSU-750 in the boiler above the weight with the speaker going in the square tender. So that way I only need three wires going to the tender. Two for the speaker and one for the tender wheel pickup.

With your other locomotives I suspect you will need something like the Tsunami TSU-1000. The problem with the brass Vanderbuilts is fitting a speaker in them. I have found ways to fit them in the locomotive and with my SP 2-6-0 I had to put the speaker in the inside top of the cab which work out pretty good.

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Posted by richg1998 on Wednesday, August 4, 2010 4:33 PM

Measure the motor current at 12 volts DC with a light load on the drivers. The Tsunami is rated at 1 amp.

http://www.soundtraxx.com/dsd/tsunami/1000.php

Isolate the one motor brush that connects to the chassis. Wire the install according to the instructions with the decoder and download the manuals from SoundTraxx.

Sounds like you need to do quite a lot of reading about DCC It is not plug and play, especially with brass locos. The Tsunami go for about $95 each from Litchfield Station.

There are cheaper sound decoders but I do not use them. Others will comment.

Rich

If you ever fall over in public, pick yourself up and say “sorry it’s been a while since I inhabited a body.” And just walk away.

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  • From: North Carolina
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Posted by Aikidomaster on Thursday, August 5, 2010 6:49 PM
All of the tenders are the square variety. No Vandy tenders.

Craig North Carolina

  • Member since
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Posted by WPAllen on Thursday, August 5, 2010 7:58 PM

That makes things a lot easier. I will disregard the current draw of the motor for now. You may want to change the motors out to a can style if they are open frame. Not all that hard to do.

With the square tender you can most likely put the decoder and speaker in the tender. I'm doing a Western Pacific 2-8-0 and there is not room in the tender for both the speaker and the decoder the way the tender is designed. So only the speaker will go in the tender and the decoder will go in the locomotive boiler area for that set up. You may have to drill some holes in the bottom of the tender for the speaker. Sometimes they are already there.

 With both the speaker and decoder in the tender I run a 5 wire plug between the tender and the locomotive. Wire one is headlight. Wire two is motor. Wire 3 is right wheel locomotive pickup. Wire four is motor and wire five is headlight. That way if you reverse the plug the locomotive only goes backward,

 Regarding the motor you have to make sure both brushes are isolated and are not grounded to the frame. If you use and LED for the headlight I use a 1K ohm resistor in series with one of the wires. If you use a light bulb the resistance will depend on what the voltage of the light bulb is. It could be 1.5v, 3v or maybe 12 v.

 I have only used the Tsunami decoders by Soundtraxx so far. They are very good quality. Fit the biggest speaker you can in the tender.

 

 

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Posted by rrinker on Thursday, August 5, 2010 9:07 PM

 I would recommend having a professional do the first one then carefully look over what they did and how they did it, and copy that for the remaining units.  If they are different makes and vintages of brass there may not be a one size fits all solution, as motor types and wiring can and does vary between different makes and even different models produced at different times by the same builder. Older large open-frame motors may draw too much current, or at the very least will require alittle creative work to isolate the brushes. More modern models with can motors may be just fin in the current department but need some creative work to remount the motor in an insulated cradle to isolate it from the frame. With others it may simply require you to find just which wire goes where and make the appropriate connection. The critical thing with a decoder is to make sure there is absolutely no way for the motor output wires to touch the track input wires - most decoders will be instantly destroyed if this happens. On models where one side of the motor is supplied power via the loco frame, the hardest part of the install is often isolating the motor. Once you get it to the point that the only way power can get to the motor is through the wires connected to the motor terminals, the rest is fairly easy.

                                              --Randy

 


Modeling the Reading Railroad in the 1950's

 

Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.

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Posted by trainnut1250 on Friday, August 6, 2010 5:35 PM

Craig,

 
From my limited experience installing sound decoders in brass steam locos: 

1. Mount the decoder and speaker in the tender if you can.  Much easier for the first install.


2.  Check the electrical pick up reliability on you locos.  Try creeping them at low speed in DC.  If they stall, consider adding more pick-ups to the drivers or tender trucks (depending on the loco).  Sound decoders like a steady, un-interrupted current supply.  Bare minimum - solder a wire from the tender trucks to the floor of the tender.


3.  Are there pre-drilled holes in the tender floor??  If not, you will want to be extra careful when drilling to not bend, distort or warp the floor when applying pressure with a drill or drill press, (recommended).  You will probably have to drill holes for the wires even if the tender is pre-drilled.  Slow and steady is the key.


4.  Are these locos painted?  Do they have headlights installed?  Operating front couplers?  You might want to complete these tasks before decoderizing.  Caveat: I have several unpainted brass locos with sound decoders in them that will have to taken apart later when they are painted….I figure this will be years from now so I am willing to redo some of the work when it comes time to paint, so that I can run ‘em now.


5.  Use the micro TSU if the motor amp draw is low enough.  This leaves room for the biggest speaker that you can find and a capacitor.  Even large locos never seem to have enough room in the tender.


6. Skip the wire plugs and hardwire the engine and tender together.  I have found the plugs are clunky, take lots of time on the install and I am not taking the locos anywhere, so the locos never go in boxes.  A recent count of hose connections between loco and tender on a small real, live Sierra 2-8-0 was over 10, so lots of wires painted as hoses aren’t un-prototypical.


7. Get some ultra fine wire from Minatronics etc to make your connections between tender and engine.


8.  Consider the high bass speakers.  They do sound real good.


9.  Use the stay alive capacitor.  Consider upping the stay alive capacitor to the largest size the you can fit in the loco.  I’m shooting for 5K mfd.  Haven’t been able to find any small enough.  I have used some big caps (1.5k plus) in some tests with the Tsunami and it does smooth out performance and eliminates momentary power glitches.  Use a diode/resistor to slow down power in rush on DCC system short reset/start-up.


10.  Find some one local who has lots of brass experience.  There are lots of tricks and gotchas.  I know a couple of experts and they have rescued me a couple of times.  Very handy…


11. Google Mark Schutzer.  He has a lot of info on DCC installs in brass


I hope these tips help.  Good luck with the installs.  I have not regretted taking the time to put decoders in my brass locos.

 

Your Mileage may vary,

 

Guy

 

see stuff at: the Willoughby Line Site

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Posted by Allegheny2-6-6-6 on Monday, August 9, 2010 9:57 PM

Aikidomaster
I have several N&W brass steam locomotives. I want to add DCC decoders and sound. I am not what one would call an expert in the field of electronics, so I need something that is relatively simple to install. Obviously, good sound quality is a priority. What would you suggest? I have 2-8-0, 2-8-2. 4-8-4, and 2-6-6-4's.

 

 

My suggestion:    http://www.hosteamcentral.com/

When it comes to brass locomotives there is no one better in my O/P prompt professional service at a good price. I'll mess around with decoder installations on my resin locomotive to some extent so I know equally if not more important then the decoder is the speaker and enclosure. I have had some good results using bass reflex speakers in home made lead enclosures I fabricated using sheet lead. The density of the lead cut reverberation down to zero resulting in a better quality sound. and the extra weight don't hurt neither. All that being said when it comes to all things brass locomotives Jan Willard is your guy.

Just my 2 cents worth, I spent the rest on trains. If you choked a Smurf what color would he turn?

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