RGB LED Strips with Arduino I am trying to control an RGB LED strip with an Arduino. I have followed the tutorials in both of these websites: 
Using MOSFETs: https://learn.adafruit.com/rgb-led-strips?view=all


Using LED Amplifiers: http://www.instructables.com/id/LED-Strip-Controller-w-LED-Amp-Arduino/


I have tried both setups and none of them work for me. When I try the setup with the MOSFETs, I am able to control each color but the blue LEDs are dimmer than the red and green, and therefore I can't mix any colors with blue.

When I try the LED Amplifiers, I am not able to control any light at all. Only the blue LEDs light up but the red and green dont. Also the blue LEDs stay ON the whole time and the only way to turn them off is to disconnect them from the DC power source. 
What am I doing wrong?
For the mosfet circuit. Are you using an external power supply? The reason why you cannot mix any color might be due to the fact that you're not providing enough current to the led strip, so it just work fine when turning on each channel individually. Check the current the led strip draws (which usually is provided as amp per channel per meter) and use a power supply that can provide enough current for it.

From the adafuit page


  Connect a 9-12V power supply to the Arduino so that Vin supplies the high voltage to the LED strip. If you want, you can also just use a separate wire that connects to a power supply that provides about +12V. Make sure to connect the ground of that supply to the ground of the Arduino/MOSFETs!