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Forum Thread Details
  • Replies 12 replies
  • Subscribers 417 subscribers
  • Views 1574 views
  • Users 0 members are here
  • transistor
  • help
  • rc
  • please
  • buzzing
  • motor
  • arduino
Related

Transistor Help

e14 Contributor
e14 Contributor over 12 years ago

I'v bin working on an arduino powered rc robot, I'v pulled out the old chip and my arduino is plugged into the motor via transistor and pins, the transistor has an external supply and grounds are connected but, all it does is make a weird buzzing in the motor. the buzz does change tone witch makes me think the arduino is doing something. I will put my code and pic of wiring below. please help.

 

     1k resistor and the transistors # is 2N 2904 331 and the power supply is a 6v rechargeable that came with the car

image

 

int motorPin = 9;

 

 

void setup(){

  (motorPin, OUTPUT);

}

void loop(){

  analogWrite(motorPin, 255);

  delay(1000);

  analogWrite(motorPin, 200);

  delay(1000);

  analogWrite(motorPin, 100);

  delay(1000);

  analogWrite(motorPin, 0);

  delay(1000);

}

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  • e14 Contributor
    e14 Contributor over 12 years ago in reply to dougw

    I googled the part and it said is a voltage regulator is that any different then a resistor? Part: l7805cv

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  • dougw
    dougw over 12 years ago in reply to e14 Contributor

    Yes it is quite different from a resistor - a voltage regulator outputs a fixed voltage - it is not a switch like a transistor either - it won't turn off the motor. It sounds like you connected the ground pin of the regulator to your arduino. This component and this circuit is a long way from doing what you want. Peter's description of a FET transistor circuit should work fine. Or there are many simple arduino motor driver circuits described on the internet.

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