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Expanding the FM band

This has been discussed numerous times over the years, and a large expansion of the FM band simply isn't going to happen.

The one thing that actually is feasible is to open up the use of 87.7 and 87.9 MHz to more than just analog Channel 6 TV stations pretending to be FM radio stations.

They should probably allow translators to use 87.5/7/9 but maybe not full powered stations. Since digital TV stations use less of the airways I wonder if a digital station on channel 6 would occupy enough space to cover 87 MHz? Or if a low powered analog broadcast would interfere the digital TV operations but not be affected by anything on 88 MHz? Apparently there is at least one translator in Nevada licensed to 87.9 so maybe it will be considered.
 
As long as we are looking at that idea,
why not consider how the land-mobile community
shares the seven bottom UHF channels
in areas that are so far apart so as not to interfere?
Have radio stations where no TV stations are because ideally,
the most efficient way to manage a limited spectrum is to
place whatever services are needed where they are needed.
 
They should probably allow translators to use 87.5/7/9 but maybe not full powered stations. Since digital TV stations use less of the airways I wonder if a digital station on channel 6 would occupy enough space to cover 87 MHz? Or if a low powered analog broadcast would interfere the digital TV operations but not be affected by anything on 88 MHz? Apparently there is at least one translator in Nevada licensed to 87.9 so maybe it will be considered.

I keep reading about "licensed" 87.9 translators. What's the FCC loophole that allows this?
 
I keep reading about "licensed" 87.9 translators. What's the FCC loophole that allows this?
Channel two-hundred has been added to the amended table of allocations
 
There may be much more to the process, but as I understand it, if there are no other frequencies available and 87.9 is not going to cause interference, it can be allocated and is in a few instances across the country. As I recall, the first was a California high school station, that I believe had been on a different frequencies but as a 'secondary' service, was forced to change frequencies.

For those that know complete details, feel free to correct my statement and share the details. I'd be curious to know if an LPFM has tried this after being displaced.
 
Channel 200 has always been a real FM channel in the table of allocations going back to the early 70's, if not earlier. In the days before DTV (prior to 2009), 87.9 was limited to class D stations well beyond the interference contour to TV-6. Anything more would likely interfere with the TV-6 aural carrier when ducting occurs. More over, every digital receiver ever produced has this channel inside (whereas many do not go down one more to 87.7 and TV-6's aural carrier.) If in doubt, check the table of channels in one of the historic publications of the rules.

Since the first DTV compaction (2009), the FCC has loosened the use and spacing restrictions for 87.9 to a great extent given there are mainly LPTV's on TV-6. LPTV's don't need as much protection. However, with the reality that some UHF full power TV's may opt to return to TV6 for their new post-compaction allocation, that again may change back to a more restrictive spacing.

As for expanding the FM band, it's a non-starter and put to bed earlier this decade. Beyond the existing allocations for TV below (continued to be used for such) and aviation above, there are only a couple nations which employ a FM broadcast band outside of 88-108. This would make the manufacture of radios more challenging and divergent. Never mind there are treaties and international allocations involved which would require renegotiation. Further, the AM expansion to 1700 proved to be a boondoggle to the stations which went there. There is no point in revisiting/repeating that history.

RR
 
There are two legally licensed stations currently operating on 87.9 MHz in the USA: KSFH in Mountain View, California (10 watts Class D), and K200AA in Sun Valley, Nevada (28 watts, translating KAWZ).
 
Channel 200 has always been a real FM channel in the table of allocations going back to the early 70's, if not earlier. In the days before DTV (prior to 2009), 87.9 was limited to class D stations well beyond the interference contour to TV-6. Anything more would likely interfere with the TV-6 aural carrier when ducting occurs. More over, every digital receiver ever produced has this channel inside (whereas many do not go down one more to 87.7 and TV-6's aural carrier.) If in doubt, check the table of channels in one of the historic publications of the rules.

It might be wiser to expand the FM band to 87.5 while protecting the interference contours of the few TV stations broadcasting on RF 6. More than a few receivers can tune to 87.5 and almost all can tune to 87.7. I can't wait for my HD radio to lock on to a full-power hybrid signal on 87.5-87.9 and switch between the HD channels.
 
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