2468's MXP Color Organ

[VacioArconte]

This fall we at Team Appreciate have been working on prototyping a color organ - a device that listens for frequencies and flashes LEDs when there is a spike in a certain frequency band. We're calling our color organ the BeatBoard.

As you may know, the new roboRIO has an MXP (myRIO Expansion Port) which allows teams to provide additional input to and output from the roboRIO. We are using the MXP as a source of power, and our color organ will output a signal on the DIO pins. Because of this, teams will be able to actuate motors and flash LEDs based on what the BeatBoard receives from external noise.

The circuit itself includes an electret mic (an electret mic is an induction-based microphone that has a permanently embedded electrostatic charge), which has its signal passed through an op-amp (operational amplifier) circuit. From there, the signal passes through a series of transistors, resistors and capacitors to modify the signal. Then the signal passes through three LEDs and three optoisolators. From there it goes to the DIO pins on the MXP to be acted upon by the program. (You can find our basic VI attached)

We started out using this circuit and a breadboard as our prototype.
After that, we added the op-amp to the circuit and made the circuit in Eagle, a free PCB development tool. We haven't exhaustively tested the resistor and capacitor values to tune the circuit appropriately. Early this year, we'll be testing different resistor/capacitor values to get a well-functioning BeatBoard. Hopefully you'll be able to see our robot flashing its lights in time with the music at Dallas, Alamo and Hub City.

Below you can find our Eagle files as well as a picture of the board. Let us know what you think of the circuit and the idea.