Quote:
Originally Posted by Aussieguy
if you can trace your wiring for the TV and antenna
make sure there is NO other wire running alongside it
DC current is good at creating electrical interference
if they are tied together ... loosen them
OR
magnets placed on the wire may reduce the loss
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They may look like magnets, but they are NOT. They are ferrite beads, sometimes referred to as chokes. With every current flow there is a corresponding magnetic field. (Don't believe it? Hold a compass near a DC single conductor--not a duplex pair--and turn the current on and off and watch the needle jump.)
Running a conductor carrying current with a high-frequency component through a ferrite bead suppresses the magnetic field, and consequently the high-frequency current.
As you know, the US FCC tests devices to see if they produce enough emissions to interfere with other devices. This is called Radio Frequency Interference (RFI). These devices need to have the high frequencies (sometimes called radio frequencies or RF) internally, and are often packaged in a grounded metal case which contains the electric field. The RFI emission comes from unshielded cables which radiate the electric field acting as an antenna. The longer the cord, the stronger the radiation.
The ferrite bead (not a magnet), installed close to the source, prevents the RF energy from propagating down the cable and becoming an efficient radiation source.
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