Sound in LEGO PF Trains

[legoboy3998]

So today while at work (cutting grass I do alot of thinking while cutting grass) I had an Idea, how about adding sound to LEGO Trains. do any of the PF techies know if there is built in logic in the IR receiver to for momentary activation (i.e. push button where as long as the button is pressed the sound plays) such would be useful for train horns and bells? if this is possibly this would allow using model railroading sound decoders powered buy the PF battery and IR receiver. so does anyone have any idea of the possibility of this working?

Sal

WFB, WI

[Toastie]

So today while at work (cutting grass I do alot of thinking while cutting grass) I had an Idea, how about adding sound to LEGO Trains. do any of the PF techies know if there is built in logic in the IR receiver to for momentary activation (i.e. push button where as long as the button is pressed the sound plays) such would be useful for train horns and bells? if this is possibly this would allow using model railroading sound decoders powered buy the PF battery and IR receiver. so does anyone have any idea of the possibility of this working?

Sal

WFB, WI

Hi Sal,

the LEGO "bang-bang" PF IR remote (#8885 S&H) should do what you want. As long as you "push" one of the buttons the corresponding output on the receiver is turned on @full power (no PWM, the output is plainly delivering full DC voltage).

Regards,

Thorsten

[The Yellow Brick]

I have already started a very similar topic over here.

Edited August 20, 2010 by The Red Brick

[legoboy3998]

Toastie Icon Posted Today, 03:05 AM

Hi Sal,

the LEGO "bang-bang" PF IR remote (#8885 S&H) should do what you want. As long as you "push" one of the buttons the corresponding output on the receiver is turned on @full power (no PWM, the output is plainly delivering full DC voltage).

Regards,

Thorsten

Thorsten, would this remote allow using the single pin mode of the PF IR receiver? What I want to do is add a sound decoder that would act like a decoder in a DCC type Model train. Where the engine sound would increase/decrease with the speed of the motor. As well as having a horn and bell that would be activated by a push button and stay on as long as pressed. Ive heard the NXT intelligent brick (#9841) will allow using this mode but that would be super expensive. I want everything to be individually controlled and I dont think possible with the current remotes.

SAL

WFB, WI

[Toastie]

Thorsten, would this remote allow using the single pin mode of the PF IR receiver? What I want to do is add a sound decoder that would act like a decoder in a DCC type Model train. Where the engine sound would increase/decrease with the speed of the motor. As well as having a horn and bell that would be activated by a push button and stay on as long as pressed. Ive heard the NXT intelligent brick (#9841) will allow using this mode but that would be super expensive. I want everything to be individually controlled and I dont think possible with the current remotes.

SAL

WFB, WI

I guess I am lost here, sorry, my fault:

1) What do you exactly mean by "single pin mode"?

2) Sound: If you want to in/decrease the sound level with speed setting, then you would need to somehow need to "read" the PWM outputs of the IR receiver. You could use a bridge rectifier (good for both fwd and bwd) + capacitor (+ possibly small load resistor) to get a "PWM power level corresponding DC voltage". I presume the response would be pretty much non-linear though (as you can see by attaching an old 9V lamp to the IR receiver output: Even at PWM power level 1, the lamp is already pretty bright)

3) The horn and bell module would work with the on/off remote, as long as this sound module goes off when powered on. During that time though, it would be tough to transmit other IR signals.

4) You may control many things individually, that would require more IR receivers (and naturally "block" IR channels of course)

5) NXT: This is something I am looking into. The NXT along with a HiTechnic IR Link sensor would be able to mimic both remotes, as well as transmit IR signals on more than one channels "quasi-simultaneously". But you are right: The NXT is still expensive, even at BrickLink, and the IR Link Sensor would be another 50 bucks. I just happen to have the NXT since 2 years now - was a present.

Well maybe I am totally wrong here and you are talking about something entirely different.

Regards,

Thorsten

[legoboy3998]

Toastie Icon

Posted Yesterday, 03:31 PM

I guess I am lost here, sorry, my fault:

1) What do you exactly mean by "single pin mode"?

2) Sound: If you want to in/decrease the sound level with speed setting, then you would need to somehow need to "read" the PWM outputs of the IR receiver. You could use a bridge rectifier (good for both fwd and bwd) + capacitor (+ possibly small load resistor) to get a "PWM power level corresponding DC voltage". I presume the response would be pretty much non-linear though (as you can see by attaching an old 9V lamp to the IR receiver output: Even at PWM power level 1, the lamp is already pretty bright)

3) The horn and bell module would work with the on/off remote, as long as this sound module goes off when powered on. During that time though, it would be tough to transmit other IR signals.

4) You may control many things individually, that would require more IR receivers (and naturally "block" IR channels of course)

5) NXT: This is something I am looking into. The NXT along with a HiTechnic IR Link sensor would be able to mimic both remotes, as well as transmit IR signals on more than one channels "quasi-simultaneously". But you are right: The NXT is still expensive, even at BrickLink, and the IR Link Sensor would be another 50 bucks. I just happen to have the NXT since 2 years now - was a present.

Well maybe I am totally wrong here and you are talking about something entirely different.

Regards,

Thorsten

No its ok its a complicated thing I want to do. Ill see if I can explain it better.

1) I read in the LEGO PF IR receiver protocol pdf from LEGO that the IR receiver was capable of a "single pin mode" which allows you to control the pins (9v 0v c1 and c2) individually.

2) The sound of the engine shouldnt be a problem it would just be connected in the same way the train motor is so as the motor voltage increases and decreases the sound level would do the same (to simulate acceleration and deceleration).

3) The horn and bell are the sticky issues. If one can be connected to say c1 and the other to c2 allowing you to activate them individually when you want, say when you approach a station you could ring the bell or a grade crossing you could blow the horn.

4) The hope is to use only one IR receiver because I cant fit more than one in a loco and id like to only use one channel per train.

5) Yeah not having any NXT stuff and only wanting to use it for this one thing it would be a waste if it didnt work so Im kind of hopin to find someone with the knowledge and experience with PF and NXT to know if what im saying might be possible or if it isnt due to what ever.

Hopefully it is a little more clearer now. I dont know if anyone will really be able to help anyway. I went to a local hobby shop today and talked to them and I may not even be able to connect the sound module to the LEGO components in a manner which would allow the control I want. (I would use a PF extension wire and cut it and connect the wires to the module as needed.) It doesnt help that im trying to use to incompatible systems.

Sal

WFB, WI

[Toastie]

No its ok its a complicated thing I want to do. Ill see if I can explain it better.

1) I read in the LEGO PF IR receiver protocol pdf from LEGO that the IR receiver was capable of a "single pin mode" which allows you to control the pins (9v 0v c1 and c2) individually.

2) The sound of the engine shouldnt be a problem it would just be connected in the same way the train motor is so as the motor voltage increases and decreases the sound level would do the same (to simulate acceleration and deceleration).

3) The horn and bell are the sticky issues. If one can be connected to say c1 and the other to c2 allowing you to activate them individually when you want, say when you approach a station you could ring the bell or a grade crossing you could blow the horn.

4) The hope is to use only one IR receiver because I cant fit more than one in a loco and id like to only use one channel per train.

5) Yeah not having any NXT stuff and only wanting to use it for this one thing it would be a waste if it didnt work so Im kind of hopin to find someone with the knowledge and experience with PF and NXT to know if what im saying might be possible or if it isnt due to what ever.

Hopefully it is a little more clearer now. I dont know if anyone will really be able to help anyway. I went to a local hobby shop today and talked to them and I may not even be able to connect the sound module to the LEGO components in a manner which would allow the control I want. (I would use a PF extension wire and cut it and connect the wires to the module as needed.) It doesnt help that im trying to use to incompatible systems.

Sal

WFB, WI

Hi Sal,

I looked up the LEGO PF RC document, I guess this is what you are referring to, right?

1) You can control C1 and C2 individually, but not the 9V and 0V line (That would break the daisy chain link, 9V is always connected to the power supply, could be a battery box or rechargeable (+) as well as 0V (-). That would give youo control of the bell and horn.

2) Be aware though that the PF receiver output is not analogue voltage corresponding to the power level, but pulse width modulated (PWM). Power level "1" = short pulses of +9V, power level "4" = longer pulses, and full power = always on. So when you want an analogue voltage in some way proportional to the power level, you need to rectify the pulses, as I said before (Bridge rectifier + capacitor + your generator as load?).

3) Withe what I said in 1): You could hook-up the bell to C1 and 0V and the horn to C2 and 0V. That would give you control of both with one output, the sound + motor with the other.

4) See above.

5) Well, so far TLC has not given us any other device than the NXT/HiTechnic IR Link that I know do the magic to control the set-up sketched above. It should be possible though. I coudl try and do such an experiment (NXT + IR Link + PF receiver + pin control), would take a little time though.

Regards,

Thorsten

[legoboy3998]

Hi Sal,

I looked up the LEGO PF RC document, I guess this is what you are referring to, right?

1) You can control C1 and C2 individually, but not the 9V and 0V line (That would break the daisy chain link, 9V is always connected to the power supply, could be a battery box or rechargeable (+) as well as 0V (-). That would give youo control of the bell and horn.

2) Be aware though that the PF receiver output is not analogue voltage corresponding to the power level, but pulse width modulated (PWM). Power level "1" = short pulses of +9V, power level "4" = longer pulses, and full power = always on. So when you want an analogue voltage in some way proportional to the power level, you need to rectify the pulses, as I said before (Bridge rectifier + capacitor + your generator as load?).

3) Withe what I said in 1): You could hook-up the bell to C1 and 0V and the horn to C2 and 0V. That would give you control of both with one output, the sound + motor with the other.

4) See above.

5) Well, so far TLC has not given us any other device than the NXT/HiTechnic IR Link that I know do the magic to control the set-up sketched above. It should be possible though. I coudl try and do such an experiment (NXT + IR Link + PF receiver + pin control), would take a little time though.

Regards,

Thorsten

Yeah thats pretty much what I want to do. Itd be awesome if you could experiment with it, itd be nice to know if it works before I go spend $300+ for the NXT parts. Ill work on the wiring part later this winter when I have more free time.

Sal

WFB, WI

[legoboy3998]

ok heres a different one.

I want to wire a MRC on-board sound Module with transmitter into a LEGO locomotive I built. The locomotive is powered by a DC battery wired to a IR receiver. The output of the IR receiver runs to the motor. The LEGO system has 4 wires, 9v, 0v, C1, and C2. When the battery is on and the seed is at 0, the 9v to 0v carry power. When the motor is set to full foreward, C1 has power, in reverse C2 has power, in both motor positions the 9v to 0v also has power. So would I connect the red (track pickup) to the 9v, the black (track pickup) to the 0v, the orange (motor +) to C1 and Grey (motor -) to C2? The sound Module has a NMRA standard 8 pin plug. I want to wire the module so the bell and horn and prime mover sounds work?

NMRA standard 8 pin plug:

http://mrr.trains.com/~/media/import/images/d/8/7/mr_ce_5-02_wiringdcc_01.ashx?mw=900

MRC module info:

http://www.modelrectifier.com/resources/trainsound/0001000-1001ins.pdf

If there is any other specific info that would be helpful let me know and Ill try to answer any questions. Hopefully someone can help thanks.

Sal

WFB, WI

[Duq]

I'm not sure if that will work. In the PF system the 0V and +9V lines are 'always on', just like the track in a DCC system.

However the PF speed controller does not regulate the voltage on C1 and C2 but uses PWM to control motor speed. While that works fine for a motor I'm not sure whether it'll work for your sound board.

[Snapshot]

I'm not sure if that will work. In the PF system the 0V and +9V lines are 'always on', just like the track in a DCC system.

However the PF speed controller does not regulate the voltage on C1 and C2 but uses PWM to control motor speed. While that works fine for a motor I'm not sure whether it'll work for your sound board.

I think the way round this is to add a bridge rectifier across C1 & C2, leading to the sound board. I'm pretty sure that's how the PF lights work. In fact, replacing the LEDs with the sound card might do all the work for you.