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Television Broadcast
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Over-the-air television broadcasting in the United States uses the following spectrum. Each TV channel is 6 MHz wide. Digital broadcasting is by the ATSC standard. Some Low Power Television (LPTV), TV translators, and Class A television stations continue to broadcast in analog mode using the NTSC standard, but are mandated to transition to digital by September 1, 2015; however, the FCC has proposed extending this deadline in document FCC 14-151 (available under the related documents section).
VHF TV |
54-72 MHz: | Channels 2-4 |
76-88 MHz: | Channels 5-6 |
174-216 MHz: | Channels 7-13 |
UHF TV |
470-512 MHz: | Channels 14-20 (may be used for land mobile in major cities; see below) |
512-608 MHz: | Channels 21-36 |
608-614 MHz: | Channel 37 (not used for TV broadcasting) |
614-698 MHz: | Channels 38-51 |
Portions of channels 14-20 (470-512 MHz) are used by the Private Land Mobile Radio Service (PLMRS) in the following metropolitan areas:
Boston MA | channels 14 & 16 |
Chicago IL | channels 14 & 15 |
Dallas/Ft. Worth TX | channel 16 |
Houston TX | channel 17 |
Los Angeles CA | channels 14, 16 & 20 |
Miami FL | channel 14 |
New York NY/NE New Jersey | channels 14-16 |
Philadelphia PA | channels 19 & 20 |
Pittsburgh PA | channels 14 & 18 |
San Francisco-Oakland CA | channels 16 & 17 |
Washington DC | channels 17 & 18 |
PLMRS service is allowed by the FCC's rules in Cleveland OH (14 & 15) and Detroit MI (15 & 16), but interference issues with Canada prevent PLMRS from being deployed there.
A useful characteristic of digital (ATSC) signals is the addition of a narrowband pilot tone on the RF carrier. The pilot tone is at a nominal frequency of 309.440559441 kHz above the bottom edge of the channel, although the FCC may require small frequency offsets on a station-by-station basis to avoid interference between pilot tones of co-channel TV stations. Ancillary uses of the pilot tones include, for example, monitoring for sudden enhanced propagation events, such as meteor burst or sporadic E.
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Channelized Bands |
Band | Channel | Use | Service | Table |
54 - 60 MHz | 2 | Broadcast Television (VHF) | Broadcasting | N |
60 - 66 MHz | 3 | Broadcast Television (VHF) | Broadcasting | N |
66 - 72 MHz | 4 | Broadcast Television (VHF) | Broadcasting | N |
76 - 82 MHz | 5 | Broadcast Television (VHF) | Broadcasting | N |
82 - 88 MHz | 6 | Broadcast Television (VHF) | Broadcasting | N |
174 - 180 MHz | 7 | Broadcast Television (VHF) | Broadcasting | N |
180 - 186 MHz | 8 | Broadcast Television (VHF) | Broadcasting | N |
186 - 192 MHz | 9 | Broadcast Television (VHF) | Broadcasting | N |
192 - 198 MHz | 10 | Broadcast Television (VHF) | Broadcasting | N |
198 - 204 MHz | 11 | Broadcast Television (VHF) | Broadcasting | N |
204 - 210 MHz | 12 | Broadcast Television (VHF) | Broadcasting | N |
210 - 216 MHz | 13 | Broadcast Television (VHF) | Broadcasting | N |
470 - 476 MHz | 14 | Broadcast Television (UHF) (may be used for land mobile in major metro areas) | Broadcasting | N |
476 - 482 MHz | 15 | Broadcast Television (UHF) (may be used for land mobile in major metro areas) | Broadcasting | N |
482 - 488 MHz | 16 | Broadcast Television (UHF) (may be used for land mobile in major metro areas) | Broadcasting | N |
488 - 494 MHz | 17 | Broadcast Television (UHF) (may be used for land mobile in major metro areas) | Broadcasting | N |
494 - 500 MHz | 18 | Broadcast Television (UHF) (may be used for land mobile in major metro areas) | Broadcasting | N |
500 - 506 MHz | 19 | Broadcast Television (UHF) (may be used for land mobile in major metro areas) | Broadcasting | N |
506 - 512 MHz | 20 | Broadcast Television (UHF) (may be used for land mobile in major metro areas) | Broadcasting | N |
512 - 518 MHz | 21 | Broadcast Television (UHF) | Broadcasting | N |
518 - 524 MHz | 22 | Broadcast Television (UHF) | Broadcasting | N |
524 - 530 MHz | 23 | Broadcast Television (UHF) | Broadcasting | N |
530 - 536 MHz | 24 | Broadcast Television (UHF) | Broadcasting | N |
536 - 542 MHz | 25 | Broadcast Television (UHF) | Broadcasting | N |
542 - 548 MHz | 26 | Broadcast Television (UHF) | Broadcasting | N |
548 - 554 MHz | 27 | Broadcast Television (UHF) | Broadcasting | N |
554 - 560 MHz | 28 | Broadcast Television (UHF) | Broadcasting | N |
560 - 566 MHz | 29 | Broadcast Television (UHF) | Broadcasting | N |
566 - 572 MHz | 30 | Broadcast Television (UHF) | Broadcasting | N |
572 - 578 MHz | 31 | Broadcast Television (UHF) | Broadcasting | N |
578 - 584 MHz | 32 | Broadcast Television (UHF) | Broadcasting | N |
584 - 590 MHz | 33 | Broadcast Television (UHF) | Broadcasting | N |
590 - 596 MHz | 34 | Broadcast Television (UHF) | Broadcasting | N |
596 - 602 MHz | 35 | Broadcast Television (UHF) | Broadcasting | N |
602 - 608 MHz | 36 | Broadcast Television (UHF) | Broadcasting | N |
614 - 620 MHz | 38 | Broadcast Television (UHF) | Broadcasting | N |
620 - 626 MHz | 39 | Broadcast Television (UHF) | Broadcasting | N |
626 - 632 MHz | 40 | Broadcast Television (UHF) | Broadcasting | N |
632 - 638 MHz | 41 | Broadcast Television (UHF) | Broadcasting | N |
638 - 644 MHz | 42 | Broadcast Television (UHF) | Broadcasting | N |
644 - 650 MHz | 43 | Broadcast Television (UHF) | Broadcasting | N |
650 - 656 MHz | 44 | Broadcast Television (UHF) | Broadcasting | N |
656 - 662 MHz | 45 | Broadcast Television (UHF) | Broadcasting | N |
662 - 668 MHz | 46 | Broadcast Television (UHF) | Broadcasting | N |
668 - 674 MHz | 47 | Broadcast Television (UHF) | Broadcasting | N |
674 - 680 MHz | 48 | Broadcast Television (UHF) | Broadcasting | N |
680 - 686 MHz | 49 | Broadcast Television (UHF) | Broadcasting | N |
686 - 692 MHz | 50 | Broadcast Television (UHF) | Broadcasting | N |
692 - 698 MHz | 51 | Broadcast Television (UHF) | Broadcasting | N |
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LoJack Stolen Vehicle Recovery System
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The frequency 173.075 MHz is used for stolen vehicle recovery systems (SVRS), namely LoJack.
According to the FCC (DA 11-1551):
In 1989, the Commission designated frequency 173.075 MHz for use by SVRS licensees on a shared basis with the Federal Government. LoJack has developed and operates a stolen vehicle recovery network in cooperation with state and local police departments across the nation. The Commission authorizes SVRS operations on frequency 173.075 MHz on a shared, non-exclusive basis.
Under the traditional stolen vehicle recovery procedure, LoJack’s network operates as follows: LoJack and the licensed law enforcement agency install in each LoJack-registered vehicle a vehicle location unit (VLU) that remains dormant until the owner reports a vehicle theft. Once police receive a stolen vehicle report, the officials send an electronic message to a central law enforcement computer, which causes a network of radio base stations to broadcast an activation message on frequency 173.075 MHz that instructs the particular VLU to begin transmitting a brief “tracking” message, also on frequency 173.075 MHz. Vehicle tracking units located in law enforcement vehicles receive the VLU tracking message, which contains a unique reply code.12 Police identify the vehicle make, model, and registration from the reply code and then track the stolen vehicle by homing in on the VLU, which continues to send tracking messages, using vehicle tracking units.13 In 2008, the Commission extended the uplink mobile duty cycle to permit enhanced tracking capability.14 Specifically, the longer uplink duty cycle allows newer VLUs with global positioning system (GPS) technology to transmit GPS coordinates in the tracking message, which provides police the exact latitude and longitude coordinates of the stolen vehicle.
In 2008, the Commission also expanded the scope of the SVRS rules, which previously had allowed only for the tracking of stolen vehicles, to also allow for the tracking of missing persons and individuals at risk, as well as lost or stolen cargo and hazardous materials. As we describe in more detail below, the purpose of the instant Waiver Request is to further facilitate SVRS operations, particularly regarding the tracking of missing persons and individuals at risk, through new technology and an expanded pool of eligible SVRS users. LoJack states that it “is developing a system to track persons at risk, such as Alzheimer’s patients, nursing home residents with dementia, and children with disabilities, using in part the 173.075 MHz frequency.” According to LoJack, “persons at risk would wear wristwatch-like devices” that have a function similar to VLUs. When authorized parties or entities activate these wearable devices, the wearers of the devices “could be tracked by the same tracker device currently installed in police vehicles that is now used to track stolen vehicles.”
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Frequencies |
Frequency | Bandwidth | Use | Service | Table |
173.075 MHz | 20 kHz | LoJack | - | N |
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