One Who Knows said:
Those of you who know a little bit about the actual history of radio would know that in the industry's earliest days, there were no regulations. Stations were allowed to just come on the air and transmit whereever they wanted at whatever power they could come up with for the time (which usually wasn't that much).
The AM/Standard Broadcast Band became an absolute mess. Stations interfering with other stations. And the Federal Radio Commission was born to fix it. Their first move? Shut off about 150 stations to "clear" the band.
If a "pirate" band were to actually happen, I would suspect it wouldn't be long before it would be about as listenable as, let's say...CB Channel 19 is today. And, since "pirate mentality" would probably rule, how long would it be before the 20-40 watt "rule" would be ignored?
Well first, if we're going down to the 85.1 - 87.5 band, there'd be no point in even broadcasting until there were radios to RECEIVE it. I personally believe we need to expand the FM band down to 76 MHz (as in Japan), so at 76-108 MHz, there should be enough room for everybody (but then again, somebody once thought a few city blocks on a muddy island was enough for everybody in New York City.)
Secondly, you need SOME regulation. While most pirates I know of are actually pretty responsible (in spite of being....well, pirates) and don't go beyond a few watts, there will be those who are going to really push it as far as they can go. If anyone with enough $$$ can buy a 100,000 watt blaster off eBay, With no rules holding them back, they'll do it without a second thought.
I don't see the problem with a maximum of 5 watts and some antenna height restrictions with second adjacent channel spacing. Trust me, it ain't gonna be no contest between 100,000 watt stations with transmitters high up somewhere 0.4 MHz down and/or up the dial and a 5 watter somewhere down below in between.
However, distance spacing is something to be considered also. And with FM, that's a headache because EVERYBODY wants to be on FM. Then there's the digital factor. Someday, not in the IMMEDIATE future, but someday within our lifetime, radio WILL be ALL digital. I don't know of many IBOC equipped LPFMs (are there ANY out there?) right now, but I know one day, the FCC will have to either make IBOC open source or make manufacturers also include DRM decoding in new radios because something's gotta give. IBOC is out of reach and just out of the question for most LPFMs and Part 15 FM devices.
I think eventually, AM will be abandoned and that can be used as a LOCAL radio band. At lower power levels than your current graveyard frequencies, the nighttime noise shouldn't be too bad and I don't see as many AM broadcasters as I would FM. AM Stereo should be looked at again because IBOC doesn't work at all very well on AM.
My $2.00 worth.....