RC cars

Discussion in 'Wireless & RF Design' started by Nathan Hale, Jan 4, 2015.

  1. Nathan Hale

    Thread Starter Active Member

    Oct 28, 2011
    Hi folks! I have an RC car i play with. It seems to me that the car cant be controlled beyond 40 feet from the wireless joystick.
    I heard that radio waves keep traveling farther and farther and forever and ever...if that is so why doesn't my car pick up the signal from the wireless joystick and keep driving farther and farther?
    why does it seem to loose communication with the wireless joystick after about 40 feet?
    thank you
  2. MrChips


    Oct 2, 2009
    Electromagnetic waves obey the inverse-square law. Hence the signal at the receiver diminishes non-linearly the farther away it is from the transmitter. If you double the distance to the receiver, the signal is reduced by a factor of 4.
  3. jpanhalt

    AAC Fanatic!

    Jan 18, 2008
    Are you sure the remote control ("RC") for your car uses radio and not infrared. Both types are available. Infrared is usually has a much more limited range. Its range follows the same inverse-square law as MrChips mentions, but it is just less sensitive.