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March 5, 2012

Are Superpowered FM Broadcasters Affecting Mother RF Spectrum

One day not too long ago I occurred to have my spectrum analyzer connected to the outdoors discone broadband antenna. Out of curiosity I scanned the entire 1st GigaHertz of the RF spectrum, curious to see who had the strongest RF signal into my home. It turned out to be a pair of FM broadcasters. So I then focused in on the FM broadcast band spectrum.

I quickly discovered two FMs who jointly held the top signals. I measured obtained sign levels from each station of -16 dBm. These two are the strongest measured off-premises indicators at my residence in between and one,000 MHz, and probably in the entire RF spectrum. When that signal level is created throughout a seventy five ohm receiver input, it produces more than 43,000 microvolts!

Few, if any, non-broadcast broadband receiver front ends are heading to deal with a signal of that magnitude without folding into compression. It is no surprise that my sensitive monitoring receivers on outdoor antennas curled up and died whenever they had been tuned to within a couple of tens of Mhz of the FM broadcast band. That grossly extreme obtained signal degree is really needed only for getting broadcasts on electric toothbrushes!
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Notch Filter

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Fastened Film
BOD elimination and biological nitrification can be achieved using fastened movie therapy. This technique utilize s some microorganisms to treat the wastewater. It utilizes a trickling filter/activated sludge treatment process whereby a plastic media contains microorganisms, which will grow within a tower exactly where the wastewater is positioned for therapy. It is then adopted by activated sludge procedure.
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