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 uses LEGOS Power Function system and 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. C1 and C2 are motor control wires, always have full voltage and use PWM to control motor speed. The LEGOsystem has LED lights which use a bridge rectifier so that if connected in parellel to the motor would get brighter as the motor speed up. 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? Does the Prime mover sound eed constant voltage and use some other method to increase and decrease the rpm sound or does it use voltage changes to change the sound?NMRA standard 8 pin plug:http://mrr.trains.co..._01.ashx?mw=900MRC module info:http://www.modelrect...000-1001ins.pdfIf 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.SalWFB, WI
I dont think this setup would work. A dcc decoder on dc needs clean dc power. Your Lego system dosent use a clean power supply.
technically speaking
yes you could do it. But it wouldn't work very well
Your lego module puts out PWM signal. You could attach the outputs to a simple inductor/cap circuit which will turn it back into varying DC voltage (rough appoximation) The decoder in turn would run off that.
BUT
Most DCC sound decoders don't start moving until 8 volts. And you only have 9. Plus you would have to supply up to 14 watts. That's a lot for a little lego decoder. And you have to be very careful with your PWM->DC circuit
It would be better if you used something like Aristo G wire instead. Sheldon (Atlantic Central) should be able to help you out there if I remember correctly.
Don - Specializing in layout DC->DCC conversions
Modeling C&O transition era and steel industries There's Nothing Like Big Steam!
According to the MRC module info, it is designed to run on a variety of systems, including DC and Battery powered. To get around the PWM problem, the LEGO system has built in circuits to convert the power back to normal DC where the motor connects to allow for motor speed control of normal DC motors (i.e. increase voltage increase speed, I tested this with a multimeter). So it sounds like my only issue may be the Power required and according to the info it looks like it requires only 1.5 amps. So I think Ill temporarily connect it and see what happens.
Thanks for the Help.
Sal
WFB, WI
Good luck. Let us know how it works out. :-)
DigitalGriffin Good luck. Let us know how it works out. :-)
So I finally had some time to try it out. IT WORKS :) since all I need to sound module to do is provide sound, all I did is connect the red and black wire to my + and - wires from my onboard battery. This gives to module power to operate the sounds. I made the connections temporarily to test to see if it would work. Now I will have my Uncle (a model railroader) solder the wires perminently. Thanks to all for your help and advice.