# will a Bachmann 3 truck shay w/ DCC sound work on DC



## paintjockey (Jan 3, 2008)

I have a Bachmann 3 Truck Shay with Bachmann's DCC onboard sound. When on DCC the loco works fine although it's very quiet. When put on standard DC power the loco sound will only idle (ie: sit and run the air pump and blow off steam) it will not chuff. Shouldn't the loco's sound run on both DCC & DC or am I missing something? Also what is the CV to turn the sound up on the loco?

For DC power I have run it on a 5amp, 10 and 15 amp power pack, so i know power isn't an issue. the loco operates fine it's only the sound the is malfunctioning. Sorry, the headlight when turned on will blink constantly as well. I assume the loco is trying to tell me something but darned if I know  

Thanks 
Terry


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## nkelsey (Jan 4, 2008)

With no DCC signal, the sound card does not know that the loco is moving and therefore no chuff, it si not getting input about motor speed. I suggest rip out the quasimodo and install a QSI decoder, sound and motor control on DC or DCC, plus you get whistle and bell on DC by using the direction switch. About rip out, the 3 truck shays were cold soldered, the wires will disconnect from the pc boards very easily, and the plug between the tender and body have the same problem... Plus with the QSi you can later add the GWire and have radio control of you loco, with DC, DCC or Battery....if you do not want to do this yourself, talk to Mike at Throtle Up. 901-605-5252


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## TonyWalsham (Jan 2, 2008)

What sort of DC controller are you using? 

If it is a pwm type, that may be the problem. DCC decoders do *NOT* like pwm, they can get (very) "confused". 
Use only a filtered DC type of power pack/controller.


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## Greg Elmassian (Jan 3, 2008)

Terry... the sound unit was a special OEM unit made by Soundtraxx... It's based on a Tsunami. We call it a Quasinami, because it's not really large scale compliant. 

Even HO Tsunami's are touchy on large scale track voltage. The error indication, normally track power too high, is communicated by a blinking headlight. 

It should work fine on DC too, but at about 21 volts or less it goes into overvoltage mode. Also, many of them go ke-blewey anyway. 

Use the Tsunami manual to program it. First, do a full reset of the decoder. Then test it out on a dcc system, but make sure you are nowhere near 20 volts... most G scale DCC systems are 20 or 21 volts... 

If it blinks when you set it on the tracks, you have to find a way to turn the voltage down. 

Try all this stuff first. Then when it's working perfectly on DCC, try it on DC, and analog mode only, not PWM, because, again, the voltage will be too high... so no PWM mode from an Aristo TE for example. 

Regards, Greg 

p.s. just realized you said 3 truck shay... I BELIEVE that this is the same unit as was in the 2 truck shay.... putting it on the DCC program track and reading back the manufacturer's ID will confirm.


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## Tom Bray (Jan 20, 2009)

Something I ran into when I changed out my LGB Trolley controller for a Massoth DCC sound and controller. The Massoth controller doesn't like the unfiltered DC that my MRC transformers put out. I had a brief discussion with Klaus but didn't get anywhere ... I think it is a software bug but maybe someone can come up with how it might be a feature. 

My solution was to put a bridge rectifier and a large capacitor after the MRC transformer, along with a reversing switch. The rectifier kept the voltage from going over 24V when the transformer is lightly loaded and it doesn't matter which way the direction switch on the transformer is set to avoid blowing up the filter capacitor. I tried putting the filter capacitor inside the transformer case but the voltage got way to high that way. 

If you are running PWM out of your controller, you can use the same technique and it will smooth out the pulses - about a 4700uF cap at 50V should do fine. 

Tom


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## Trains West (Oct 4, 2008)

I have seen a lot of Tsunami's with dc turned off you need to check cv29


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## Greg Elmassian (Jan 3, 2008)

He said the loco runs fine on DC, but not the sound. If this is indeed a single decoder, then the analog conversion bit must be on, or it would not move... I think that logic makes sense. 

Greg


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## Trains West (Oct 4, 2008)

no way it is one decoder it would not hold up to the curent


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## Greg Elmassian (Jan 3, 2008)

Hmm... well the Bachmann 2 truck shay is a single decoder made by Soundtraxx and is basically a higher current Tsunami... 

So you are saying this is not so in the three truck shay? I have not pulled one apart, but I find it highly unlikely that bachmann designed one themselves. 

Can we get a picture from the original poster of the board(s) inside? Was there an operating manual? 

Greg


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## paintjockey (Jan 3, 2008)

First off the loco is not mine a friend gave it to me to do some other work to it and see if i could fix this problem because I have a DCC programmer. Funny, when you have a programmer people think you know what you're doing. I do not have the manual for it. 
i couldn't tell you if I used pulse width control through it. My bench tester is an old Lionel G scale transformer at max it puts out about 14v. The loco performed this way on this power before it was put on the bigger power. I do not remember what the bigger power packs were, they are not mine. I really don't want to open something that doesn't belong to me.


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## Greg Elmassian (Jan 3, 2008)

"I have a Bachmann 3 Truck Shay with Bachmann's DCC onboard sound." 

That's what I was operating under. Put it on the programming track and try to read cv 8. You should get the manufacturers id number

Use this link to see who made the decoder: *http://www.nmra.org/stan...trong>**

That is an easy first step. Then we can check what the CV settings are, knowing what the decoder is.


If you want to do programming, you need to know what the decoder is in most cases.

Regards, Greg 

*


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## paintjockey (Jan 3, 2008)

CV 8 was 141 or soundtraxx. I got on the horn w/ them and they gave me a few pointers to check namely that CV 12=1 CV 29=6 and CV 218=20. All was already setup as suggested so I went for the factory reset. Since the loco will be used on DC power I wasn't too worried about losing any changes made to the decoder. The factory reset worked and now all is well. Although with the volume turned up to max (CV 128= 0-255) the loco still isn't very loud. But the main problem was fixed. Thanks for the imput!! 

Terry


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## Greg Elmassian (Jan 3, 2008)

Great... I was pretty sure it was the "Quasinami" you should be able to use the Tsunami programming manual. 

Yep, factory reset is often what it takes. 

CV 12 = set analog mode (weird since cv 29 sets this in most decoders) 
CV 29 = analog mode, normal direction, 28/128 speed steps 
CV 218 = I cannot find anything about this CV, it appears undocumented... do you have a manual or some more info on this one? 

Glad it worked out... 

Greg


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## paintjockey (Jan 3, 2008)

Greg, the Tech said cv218 was a longshot but to check it. he had to look it up to see what the value should be. He said what it did but i cannot remember and i'm sorry but I don't have the manual. cv12 was to turn on analog chuff, i forgot to type that all in.


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## Greg Elmassian (Jan 3, 2008)

Thanks Terry, will add those tidbits to my limited knowledge of the Quasinami. 

If you ever get hold of the manual or a pdf, let me know ok? 

Regards, Greg


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