Interference
Interference
Related wiki pages: Broadband over Power Lines (BPL) What causes QRN?, Propagation, Bands, Antennas
Interference or noise (also known as QRN) is the effect of unwanted radio signals in the same frequency that one is listening to or wishes to transmit on. Interference is generally classified as being either man-made, terrestrial or cosmic.
Man made interference is created by man-made electrical devices. Broadband over Power Lines (BPL) is a good example of this. Links to another page of this wiki can be found below.
Terrestrial sources include lightning, which is generally worse in summer on the lower HF bands, due to increased numbers of storms. Rain and snow storms can also produce significant interference.
Cosmic interference results from the emission of high energy radio waves from stars including our own sun. The sun has by far the greatest effect in this category, due to its proximity to Earth.
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