FCC TV Band Devices
Joel Koltner wrote:
"Dave" wrote in message
...
The FCC and the TV broadcasters looked the other way because there is no
evidence that such activity has ever caused any interference. I can get 6
microphones to work in an occupied analog TV channel and neither notices the
other.
OK. I don't have a big problem with folks using frequencies they're not
assigned when there isn't an interference issue, although I also don't have a
whole lot of sympathy for those same folks if one day they *are* interfered
with by assigned users.
The TV Band Devices the FCC has recently begun the process of authorizing
are way more damaging than a 50 mW 65 kHz deviation FM signal.
What are the power levels? Presumably the occupied spectrum is potentially
many tens of MHz?
Luckily, these devices will not be allowed anywhere near where I work. The
FCC has banned them from the 13 biggest cities, and from within a kilometer
of a venue or stadium using wireless microphones. The proposed rules do not
require a Part 74 license for these protections.
If these are consumer-type devices, realistically how will the FCC stop their
use in those 13 cities? It'll be like GMRS where technically everyone's
supposed to be licensed yet, in actuality, I imagine that well under 1% of the
actual users a If the consumer can buy a radio off-the-shop at Wal*Mart,
there'll use it wherever they want, regardless of what FCC rules say.
---Joel
Each TVBD will be addressable and can be shut off when it consults the
database. The top 13 cities thing is probably an oversight, but it's in
the proposed law.
The proposed power for a portable device is 100 mW, except on a
first-adjacent to a DTV station, which is 40 mW. This makes no sense
because the 2nd adjacent channel is more likely to interfere.
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