DK Electronics Motor Shield Problem

Other Hardware Hardware Development
1

I have just got a DK Electronics Motor Shield and went to try it on my Arduino Mega 2560 and hooked up 1 small dc motor.

I than hooked up a 9.6v battery supply (8 rechargeable 1.2v 3000Mah Batteries) through its EXT_PWR supply terminals.

After that i uploaded a sketch example i downloaded from adafruit called 'Motor Party' and it ran the one motor connected to M2.

After it was powered the Motor Shield or Arduino started humming??

Also i read somewhere that if you are using a seperate power supply from the arduino you need to remove a jumper? which one would this be??

the shield looked something like the one at http://playground.arduino.cc/Main/AdafruitMotorShield#.UzYuEfmSxqV

any ideas?

2

I have fixed the humming problem. it happened to be coming from a loose heatsink i installed (and btw does thermal paste set?) but everytime i try to use it now it works fine but when i try to use an external power supply it sparks abit and the lights on the board and the arduino go dim. I tried to bend the vin pin out of its socket, tried again same thing happened any ideas??

3

It seems after a bit of looking at the motor shield that there was a small piece of wire bridging the gap between the power jumper that was not really noticeable and when removed fixed the problem...