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Why do my speakers pick up radio stations?

  1. Jul 27, 2008 #1
    I get random radio broadcasts coming from my logitech speakers when they are turned on but with no volume. Why is this?
  2. jcsd
  3. Jul 27, 2008 #2


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    Staff Emeritus
    Science Advisor
    Gold Member

    Because they're poorly made. Some of the wiring inside the speaker acts as an antenna, and some part of the circuit provides the diode behavior necessary for demodulation. The resulting audio frequency energy is faithfully amplified by the power amplifier, and viola, you have a radio.

    - Warren
  4. Jul 27, 2008 #3


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    Staff: Mentor

    Is this at home? Are they plugged into a computer? Do you get the radio when you unplug them from the computer?

    My company helped a building in Philly with a problem where the frame of the building was receiving radio waves and everything with a microphone or speakers on certain floors would play the radio station being broadcast from next door.
  5. Jul 27, 2008 #4

    jim mcnamara

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    Staff: Mentor

    We had to build what amounts to a Faraday cage around a computer next to WNBC in Washington DC .... long loooong ago.

    What you see is not all that uncommon, especially if there is a powerful radio antenna nearby.
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