Noise in 12 V stereo from Norcold fridge

Discussion in 'Marine Electrical / Electronics' started by Scotth, Sep 21, 2018.

  1. Scotth

    Scotth Senior Member

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    We get a pretty bad noise pick up when listening to AM radio on our Kenwood 12V marine stereo deck, it seems to be coming from our 12V Norcold fridge when it kicks on.

    Any easy solutions? Line filters? I am not sure if it is being picked up on the 12V supply or by pickup in the air.
     
  2. captjohn

    captjohn Captain

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    When your getting the noise, is the refrigerator running off of 12 VDC?
     
  3. Scotth

    Scotth Senior Member

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    Yes, we have never tried running it on AC 120V.
     
  4. captjohn

    captjohn Captain

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    You have electrical noise, created by the compressor in the unit. You can try two ways of getting rid of it, wire routing, or filtering the noise out. See if the power line for the refrigerator and the stereo are bundled together, if they are, separating them can help. If not, you need to install a filter capacitor on the line to filter out the noise. Your compressor could also be showing signs of a problem. You usually have issues when running the unit off of AC power. Their is a switching power supply in the unit that converts the AC power into DC. It uses a switching transistor that operates at 1 KHz to allow the unit to get away with a much smaller transformer. That 1 kHz tends to get on the line, but this isn't the case with your problem. Stop off at a good marine electronics store and explain your problem to them, they should be able to help you out.
     
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  5. Keelboater

    Keelboater Captain

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    Switch to FM. ;) Sorry, couldn't resist.
     
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  6. Scotth

    Scotth Senior Member

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    We would like to switch to FM:) The local station is only AM, rural AK.
     
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