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Low frequency scanners

  1. Dec 29, 2008 #1
    How much work is it to modify an am radio to receive low frequencies 10 to 200 hertz ?
  2. jcsd
  3. Dec 29, 2008 #2


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    Less effort than running the 300,000km antennae wire.

    That frequency is very specialized technology are you trying to communicate with submarines or miners?
  4. Dec 29, 2008 #3
    I want to pick up rf signals from power lines and appliances.
  5. Dec 29, 2008 #4
    how are the rf signals different from magnetic fields.?
  6. Dec 29, 2008 #5
    The bandwidth of the IF filter in the radio would be 10kHz so it makes no sense.
  7. Dec 29, 2008 #6


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    Power lines and appliances don't emit RF at line frequencies (ie 60Hz)
    They do emit some higher frequency RF which will cause interference on a radio.

    To detect the magnetic field you would need a search coil and a sensitive voltmeter or oscilloscope and have to be pretty close.
  8. Dec 30, 2008 #7
    A low pass or tunable band pass maybe with active filters and a scope unless you go the digitial signal processing root but you will have to have some sort of display whatever or meter or rising and falling tone.

    A very low frequency spectrum analsyer would be possible. You need a very small IF bandwith.. 0.1 Hz.. ish

    I don't think there is a much of a field from power line because they are balanced. The field produced by one conductor is cancelled out by another because the current is flowing in opposite directions. There is high frequency mush due to corona effects.
  9. Dec 30, 2008 #8
    Last edited by a moderator: May 3, 2017
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