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I need help with improving my AM radio reception

  1. Nov 9, 2008 #1
    I have been reading about Tesla and dipole senders. A dipole sender is like a long pole with sends out a signal at both ends. Tesla sometimes grounded his radio dipole senders so that one sending dipole was a ground. Likewise, he grounded his radio receivers.

    I live in the mountains and get terrible radio reception. All I want is decent AM reception. My understanding is that an AM receiver does not depend so much on an antenna as FM. In an effort to improve AM reception, I have attempted to ground the receiver. But all the radios I have are "modern" and have no ground provisions built into to them and have a plastic case.

    A tech-type suggested using a car radio, grounding it, and buying a transformer to convert AC into the appropriate wattage of DC for the radio. An auto radio uses the car's metal frame as a ground so this fits right in with my concept.

    Question: Would doing the above improve my AM reception?
  2. jcsd
  3. Nov 9, 2008 #2
  4. Nov 15, 2008 #3
    O yes, AM depends a lot on the antenna!

    So improving the antenna is the solution, but what you can do depends completely on the connections you have at your radio - either external ones, or internals if you're skilled enough. Some apparent metal pieces of the radio's casing may also serve as a ground connection if you're lucky.

    If you feel able to access, say, the input LC circuit of your radio, then every improvement is possible, with or without ground.

    By the way, modern AM radios have a ferrite coil instead of a wire antenna, and then grounding doesn't bring anything. Some car radios might use an external wire antenna because of the metal surroundings - I'm not sure.

    In this case (access to two contacts, either external, or internal, maybe at a car radio) you can connect bigger aerials; some designs have a ground connection, others don't.

    For a static use, you can perfectly build a huge wire or coil AM antenna which will make a huge difference with the built-in one.
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