TheBigA said:
TexasTom said:
That's a non-answer, since anyone who knows that process knows that you can't go to the FCC's website and just file an application for a new FM station. If there's not an open allotment in the FM Table of Allocations (and their probably won't be), you first have to initiate the rulemaking process to get a new frequency assigned to a particular location.
Call me naive, but the comment I responded to said "I live in a small town with 90% of the FM airwaves wide open."
I would ask, by what criteria does he believe 90% of the airwaves are open?
A principle that a lot of people don't understand is that a transmitter causes interference over a much wider area than the area to which it provides service.
(this is especially true for AM and TV, but it's also true for FM)
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The FCC regards an FM station as capable of causing interference at signal levels as low as 34dBu 10% of the time -- a station must deliver at least 54dBu (and usually 60dBu) 50% of the time to be regarded as providing service.
To phrase it differently, a Class B station (like the major NYC and Chicago outlets) is regarded as providing service to a distance of 65km. It is capable of causing interference to another station on the same frequency to a distance of 172km.
You can argue the exact figures (it depends on how cheap of a radio & antenna you want to protect!) but with any figures, interference is caused at a greater distance than that to which service is provided.
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What kind of radio was in use? Try scanning your dial with a "personal stereo" or the FM radio in your MP3 player or the clock radio in your bedroom. Write down how many frequencies have stations on them. Then repeat the experiment in your car. Chances are you'll find a LOT more stations on the car radio.
If the FCC authorizes stations on frequencies that sound open on a "personal stereo", those stations may cause interference to stations that are perfectly good in the car.
It's a bit of a dilemma for them. How cheap of a radio do you want to protect?
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In other words, just because you can't hear a signal on a given frequency, doesn't necessarily mean that frequency is open.
Second response to follow...