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Bluetooth speaker in a freight car?

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  • Member since
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Bluetooth speaker in a freight car?
Posted by JDawg on Saturday, June 5, 2021 11:45 AM

Hi. So I am thinking about addding some Bluetooth speakers into some of my freight cars. My plan is to buy some cheaper bluetooth speakers and disassemble them. Using the bluetooth chip and speaker but discarding the battery. I would like to power the setup with track power. Can this be done with a rectifier and resisters to change DCC to DC and bring the down the voltage to 3-5 volts? Is this workable, or kind of a pipe dream? Any helpful tips are appreciated. Anyone know of a good dcc rectifier?

JJF


Prototypically modeling the Great Northern in Minnesota with just a hint of freelancing. Smile, Wink & Grin

Yesterday is History.

Tomorrow is a Mystery.

But today is a Gift, that is why it is called the Present. 

DrW
  • Member since
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  • From: Lubbock, TX
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Posted by DrW on Saturday, June 5, 2021 12:42 PM

While I cannot give any advice on the technical part, I am curious what sounds your freight cars are supposed to produce. Animal sounds, like BLI's stock cars? Mechanical reefer sounds, as done by Athearn? Or engine sounds, because the engine is too small to accommodate decoder and speakers?

JW

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Posted by jjdamnit on Saturday, June 5, 2021 2:10 PM

Hello All,

DrW
I am curious what sounds your freight cars are supposed to produce(?)

I don't know what the OPs plans are for sound but...

The Colorado Model Railroad Museum in Greely Colorado runs sound cars.

The sounds produced by these cars are the "noise" of wheels over tracks- -the squeaks, squeals, and thunks.

I too am curious about the technical side of this installation.

Hope this helps.

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

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Posted by JDawg on Saturday, June 5, 2021 2:37 PM

Cattle sounds, general wheel noise, maybe some passenger announcements if I install them in some Passenger cars.

JJF


Prototypically modeling the Great Northern in Minnesota with just a hint of freelancing. Smile, Wink & Grin

Yesterday is History.

Tomorrow is a Mystery.

But today is a Gift, that is why it is called the Present. 

  • Member since
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  • From: Bedford, MA, USA
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Posted by MisterBeasley on Saturday, June 5, 2021 3:02 PM

Yes, you can do what you want, but there will be other issues, some easy and some difficult.  I added lights to a caboose.  It was, as some say, a pain in the caboose.

I don't know how Bluetooth devices respond to rectified power.  I would certainly suggest a good-sized capacitor to smooth out the rough spots, both in the rectified power and in the gaps of power from the track.  A bridge rectifier and a capacitor are simple, cheap devices, as are resistors.  However, freight cars don't normally use power, so most likely there's no provision for that.  You will need trucks with metal wheelsets and something to transfer power from the wheels inside the car.

I replaced all my plastic wheelsets with Intermountain metal wheelsets some time ago.  For power pickup I soldered a loop of stranded wire around each axle, with the connected wheels on opposite sides of the car.  This only gave me two wheels per rail, but that was enough for my application, since I only power one small interior light and two outside marker lights, and a bit of flicker doesn't matter much.  You can buy power-passing freight trucks, but they're pricey.  You could also make wheel wipes, which could also provide full eight wheel pickup.  Remember, wheel wipes add friction and will increase the rolling resistance of this cars.

I found a product called SBS4DCC and a company called Richmond Controls by Googling HO scale wheel wipes.  The just make the wheel wipers, but they're only 4 or 5 dollars a set for freight cars.

 

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

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Posted by JDawg on Saturday, June 5, 2021 3:55 PM

MisterBeasley

Yes, you can do what you want, but there will be other issues, some easy and some difficult.  I added lights to a caboose.  It was, as some say, a pain in the caboose.

I don't know how Bluetooth devices respond to rectified power.  I would certainly suggest a good-sized capacitor to smooth out the rough spots, both in the rectified power and in the gaps of power from the track.  A bridge rectifier and a capacitor are simple, cheap devices, as are resistors.  However, freight cars don't normally use power, so most likely there's no provision for that.  You will need trucks with metal wheelsets and something to transfer power from the wheels inside the car.

I replaced all my plastic wheelsets with Intermountain metal wheelsets some time ago.  For power pickup I soldered a loop of stranded wire around each axle, with the connected wheels on opposite sides of the car.  This only gave me two wheels per rail, but that was enough for my application, since I only power one small interior light and two outside marker lights, and a bit of flicker doesn't matter much.  You can buy power-passing freight trucks, but they're pricey.  You could also make wheel wipes, which could also provide full eight wheel pickup.  Remember, wheel wipes add friction and will increase the rolling resistance of this cars.

I found a product called SBS4DCC and a company called Richmond Controls by Googling HO scale wheel wipes.  The just make the wheel wipers, but they're only 4 or 5 dollars a set for freight cars.

 

 

 

I too am concerned with the nature of rectified power. I figured I would need a large capacitor bank. I also am considering getting some kadee electric pickup trucks to facilitate good contact. Any other suggestion, all are welcome!

JJF


Prototypically modeling the Great Northern in Minnesota with just a hint of freelancing. Smile, Wink & Grin

Yesterday is History.

Tomorrow is a Mystery.

But today is a Gift, that is why it is called the Present. 

  • Member since
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Posted by JDawg on Saturday, June 5, 2021 4:00 PM

I also considered leaving the battery and wiring the usb-c charger to track power, that would smooth out any problems too...

JJF


Prototypically modeling the Great Northern in Minnesota with just a hint of freelancing. Smile, Wink & Grin

Yesterday is History.

Tomorrow is a Mystery.

But today is a Gift, that is why it is called the Present. 

  • Member since
    December 2004
  • From: Bedford, MA, USA
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Posted by MisterBeasley on Saturday, June 5, 2021 4:58 PM

JDawg

I too am concerned with the nature of rectified power. I figured I would need a large capacitor bank. I also am considering getting some kadee electric pickup trucks to facilitate good contact. Any other suggestion, all are welcome!

My suggestion would be to build a system on the bench.  You can use clip leads to get track power to the bridge rectifier, then the capacitor, resistors and finally the Bluetooth device.  Use a meter to get the right voltage.  Then use your computer to transmit the sound to the receiver and see how it works.  Humming or buzzing probably says the power isn't smooth enough.  Try with a battery to make sure.

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

  • Member since
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  • From: Bakersfield, CA 93308
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Posted by RR_Mel on Saturday, June 5, 2021 7:16 PM

Yes, this is doable.  I power all my passenger cars and caboose lighting at 4 volts using track power.  I chose 4 volts because I wanted to use onboard rechargeable 4 volt Lithium cells.  I rectify the track power using a chip bridge DB107.  I run the rectified track voltage to a chip regulator LM7805 to get 5 volts.



The 1uf cap easily filters DCC power for my use.  If you need more filtering for the Bluetooth use a larger capacitor.

I run the 5 volts to a Lithium battery chip charger TP4056 that keeps the battery topped off.  The charger output is 4 volts.

This is a Drovers Caboose with a Lithium Coin Cell LIR2032 that powers the onboard LEDs.



I daisy chain my passenger cars with 4 volts from the baggage car, I use the baggage cars as the power source for my passenger cars.



Same process but using a larger battery, Lithium AA size cell.




I added single function decoders in my baggage cars to turn on and off the passenger car lighting.



Having onboard batteries gives me the advantage of powering my passenger car lighting without power to the rails, i.e. train parked at my passenger station for long periods with the lights on without track power.
 

Mel


 
My Model Railroad   
http://melvineperry.blogspot.com/
 
Bakersfield, California
 
I'm beginning to realize that aging is not for wimps.

  • Member since
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Posted by JDawg on Saturday, June 5, 2021 7:34 PM

Awesome mel, thanks! Where do you get your parts from?

JJF


Prototypically modeling the Great Northern in Minnesota with just a hint of freelancing. Smile, Wink & Grin

Yesterday is History.

Tomorrow is a Mystery.

But today is a Gift, that is why it is called the Present. 

  • Member since
    January 2009
  • From: Bakersfield, CA 93308
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Posted by RR_Mel on Saturday, June 5, 2021 8:19 PM

Since all the electronic parts stores closed here in Bakersfield eBay is my go to for almost everything.  I buy State Side if I can find what I want if not it’s the slow boat.


Mel
 
Modeling the early to mid 1950s SP in HO scale since 1951


My Model Railroad    
http://melvineperry.blogspot.com/
 
Bakersfield, California
 
Aging is not for wimps.

  • Member since
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Posted by JDawg on Saturday, June 5, 2021 9:56 PM

Perfect. I'm going to apply this to my project. Just gonna switch up the voltage regulator to fit the bill. Thanks!

JJF


Prototypically modeling the Great Northern in Minnesota with just a hint of freelancing. Smile, Wink & Grin

Yesterday is History.

Tomorrow is a Mystery.

But today is a Gift, that is why it is called the Present. 

  • Member since
    January 2009
  • From: Bakersfield, CA 93308
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Posted by RR_Mel on Sunday, June 6, 2021 12:36 PM

My little power supply is standard USB 5 volts, the TP4056 board is the 4 volt charger card.



Mel



 
My Model Railroad   
http://melvineperry.blogspot.com/
 
Bakersfield, California
 
I'm beginning to realize that aging is not for wimps.

  • Member since
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  • From: Southington, CT
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Posted by mthobbies on Friday, June 18, 2021 1:10 PM

Why not just use an accessory decoder?

Here is some info that may be interesting for my fellow electrical engineers out there: https://dccwiki.com/DCC_Power

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Posted by ndbprr on Saturday, June 19, 2021 7:51 AM

Many years ago, probably 30 years, I think it was AHM who offered a box car that made random noises. Never had one and never wanted one.  I am not into sound that much and with all the sounds offered on a dcc decoder it seems like reinventing the wheel to a large extent to me.

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Posted by RR_Mel on Saturday, June 19, 2021 9:58 AM

I have to say I really like your idea of Bluetooth!  No onboard programming necessary with the ability of easily changing the sound from the car.

I agree with you on using the existing USP power supply, just power it from the rails with a tiny DB107 chip rectifier through a LM7805 regulator to get your 5 volts.

It wouldn’t hurt to use a large capacity cap as a keep-alive and it would add to suppressing the 8KHZ DCC power.  I bought a capacitor assortment off eBay

https://www.ebay.com/itm/224161808490?_trkparms=ispr%3D1&amdata=enc%3AAQAGAAAAkKFupCbbfEO7sOoEH78hZDTA3NHP5GVV8RvAf56bUSrWYSCeW7WKex9wJLXtpHJPH0l9SUCMxhz39Ac0u8RQ4zz71zsnX585Zxh5BcUvL6oRaDxecoTSNw5cmutQGXraDHPXi9HIGrLqfBJ0jXSKuE0p0%2BwAWI201IU8MMWXCb%2FAR2%2FLQ6FB1DVZaIkBTVbKDw%3D%3D&chn=ps&norover=1&mkevt=1&mkrid=711-117182-37290-0&mkcid=2&itemid=224161808490&targetid=1262375642056&device=c&mktype=pla&googleloc=9052592&poi=&campaignid=12875707346&mkgroupid=127864788648&rlsatarget=pla-1262375642056&abcId=9300535&merchantid=110764602&gclid=CjwKCAjwq7aGBhADEiwA6uGZp5yTYagOqKvz8Y4piH84cTkV-qaqjHguwZg1P-KucwYCE6bEuNPqfxoC8DYQAvD_BwE

Great kit for experimenting.


Mel
 
Modeling the early to mid 1950s SP in HO scale since 1951



My Model Railroad    
http://melvineperry.blogspot.com/
 
Bakersfield, California
 
Aging is not for wimps.

  • Member since
    February 2007
  • From: Christiana, TN
  • 2,134 posts
Posted by CSX Robert on Sunday, June 20, 2021 7:30 PM

mthobbies

Why not just use an accessory decoder?

Here is some info that may be interesting for my fellow electrical engineers out there: https://dccwiki.com/DCC_Power

 

That site has some major misunderstandings in its description of DCC power.

  • Member since
    September 2020
  • 432 posts
Posted by JDawg on Sunday, June 20, 2021 7:42 PM

RR_Mel

I have to say I really like your idea of Bluetooth!  No onboard programming necessary with the ability of easily changing the sound from the car.

I agree with you on using the existing USP power supply, just power it from the rails with a tiny DB107 chip rectifier through a LM7805 regulator to get your 5 volts.

It wouldn’t hurt to use a large capacity cap as a keep-alive and it would add to suppressing the 8KHZ DCC power.  I bought a capacitor assortment off eBay

https://www.ebay.com/itm/224161808490?_trkparms=ispr%3D1&amdata=enc%3AAQAGAAAAkKFupCbbfEO7sOoEH78hZDTA3NHP5GVV8RvAf56bUSrWYSCeW7WKex9wJLXtpHJPH0l9SUCMxhz39Ac0u8RQ4zz71zsnX585Zxh5BcUvL6oRaDxecoTSNw5cmutQGXraDHPXi9HIGrLqfBJ0jXSKuE0p0%2BwAWI201IU8MMWXCb%2FAR2%2FLQ6FB1DVZaIkBTVbKDw%3D%3D&chn=ps&norover=1&mkevt=1&mkrid=711-117182-37290-0&mkcid=2&itemid=224161808490&targetid=1262375642056&device=c&mktype=pla&googleloc=9052592&poi=&campaignid=12875707346&mkgroupid=127864788648&rlsatarget=pla-1262375642056&abcId=9300535&merchantid=110764602&gclid=CjwKCAjwq7aGBhADEiwA6uGZp5yTYagOqKvz8Y4piH84cTkV-qaqjHguwZg1P-KucwYCE6bEuNPqfxoC8DYQAvD_BwE

Great kit for experimenting.


Mel
 
Modeling the early to mid 1950s SP in HO scale since 1951



My Model Railroad    
http://melvineperry.blogspot.com/
 
Bakersfield, California
 
Aging is not for wimps.

 

Thanks for all the help Mel. I got a similar kit on eBay. I've had to postpone the completion of this progect a bit, I got a little distracted with some lighting and dcc installs.

JJF


Prototypically modeling the Great Northern in Minnesota with just a hint of freelancing. Smile, Wink & Grin

Yesterday is History.

Tomorrow is a Mystery.

But today is a Gift, that is why it is called the Present. 

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