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RC car motor problem

  1. Mar 25, 2010 #1
    I have a RC car that uses 27mhz radio frequency and 8v power supply.
    The motor(6v,possibly)that rotates the wheels runs with interruptions,i have tried
    adding two new 0.1Microfarad capacitors(ceramic)in the same way as they were from the manufacturer, bit it didnt help,maybe the polarity matters.
    I cant figure out the problem,please help
  2. jcsd
  3. Mar 25, 2010 #2


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    Homework Helper

    The purpose of the capacitors is to reduce voltage spikes that feed back into the motor controller, also reducing electrical noise that might effect all connnected electrical components, including the receiver. Each capacitor should be connected to one of the leads and the can of the motor, using the can of the motor similar to a common ground reference.

    It would be difficult to diagnose the problem without swapping components, such as the motor controller (ESC), receiver, ... . Assuming the car also has servos for steering, do they move smoothly or do they jitter?

    Did the RC car operate without interruptions before, and if so, what has changed?

    Running a "6 volt motor" at 8 volts might be pushing it, although most "6 volt" motors can handle 7.2 volts.
    Last edited: Mar 25, 2010
  4. Mar 28, 2010 #3
    thanks, but thing is that previously there used to be a smaller motor and replaced it with a bigger one, thats the only thing that has changed.

    but I dont htink the problem is with motor, even if I conect a bulb instead of motor it also
    blinks and does not light continuosly.

    Is the whole recieving unit faulty?
    may be the VOLTAGE REGULATORS are not working properly, if yes, then how to trace which one?

    But thers one thing, when i touch the antenna, the motor stops jittering.
    Would grounding the antenna help? and how to ground it?
  5. Mar 28, 2010 #4


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    You don't want to ground your antenna.

    If the only component changed was the motor, and now you have a failure condition, then it's mostly likely a problem caused by the motor, such as excessive current or voltage being drawn by the motor. What size motor is your car's motor controller rated for?
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