In the United States, the Multi-Use Radio Service (MURS) is a licensed by rule (i.e. under part 95, subpart J, of title 47, Code of Federal Regulations) two-way radio service similar to the Citizens band (CB). Established by the U.S. Federal Communications Commission in the fall of 2000, MURS created a radio service allowing for licensed by rule (Part 95) operation in a narrow selection of the VHF band, with a power limit of 2 watts. The FCC formally defines MURS as "a private, two-way, short-distance voice or data communications service for personal or business activities of the general public." MURS stations may not be connected to the public telephone network, may not be used for store and forward operations, and radio repeaters are not permitted.
In 2009, Industry Canada (IC) established a five-year transition plan, which would have permitted the use of MURS in Canada starting June 2014.
:* Is not a foreign government or a representative of a foreign government.
:* Uses the transmitter in accordance with 47 CFR. 95.1309.
:* Operates in accordance with the rules contained in Sections 95.1301-95.1309.
:* Operates only legal, type-accepted MURS equipment.
Frequencies
MURS comprises the following five frequencies:
{| class="wikitable"
|-
! Channel
! Frequency
! Maximum<br />authorized bandwidth
! Channel name
|-
| 1
| 151.82 MHz
| 11.25 kHz
|MURS 1
|-
| 2
| 151.88 MHz
| 11.25 kHz
|MURS 2
|-
| 3
| 151.94 MHz
| 11.25 kHz
|MURS 3
|-
| 4
| 154.57 MHz
| 20.00 kHz
| Blue Dot
|-
| 5
| 154.60 MHz
| 20.00 kHz
| Green Dot
|}
Channels 1–3 must use "narrowband" frequency modulation (2.5 kHz deviation; 11.25 kHz bandwidth). Channels 4 and 5 may use either "wideband" FM (5 kHz deviation; 20 kHz bandwidth) or "narrowband" FM. All five channels may use amplitude modulation with a bandwidth up to 8 kHz. MURS falls under part 95 and was not mandated for narrow-banding, such as those of Part 90 in the public service bands by January 2013.
Because previous business band licensees who have maintained their active license remain grandfathered with their existing operating privileges, it is possible to find repeaters or other operations not authorized by Part 95 taking place. These are not necessarily illegal. If legal, such operations may enjoy primary status on their licensed frequency and as such are legally protected from harmful interference by MURS users.
thumb|alt=Line of Sight to the horizon|Calculating the horizon distance based on antenna height
Range
MURS range will vary, depending on antenna size and placement. With an external antenna, ranges of or more can be expected. Since MURS radios use frequencies in the VHF business band, they are subject to obstructions in line of sight, which includes the curvature of the Earth. The higher you can place the antennas on both transmit and receive sides (within legal limits), the further you can transmit and receive. Some antenna manufacturers claim an external antenna can increase the effective radiated power of a transmitter by a factor of 4.
Authorized modes
{| class="wikitable"
|-
! Designator
! Common name
|-
| A1D
| Amplitude modulation; on–off keyed or quantized; no modulation; Data, telemetry, telecommand
|-
| A2B
| Amplitude modulation; Digital, with modulation; Telegraphy for machine copy (RTTY, fast Morse)
|-
| A2D
| Amplitude modulation; Digital, with modulation; Data, telemetry, telecommand
|-
| A3E
| Amplitude modulation; Single analog channel; Telephony, voice, sound broadcasting
|-
| F2B
| Angle modulation, straight FM; Digital, with modulation; Telegraphy for machine copy (RTTY, fast Morse)
|-
| F1D
| Angle modulation, straight FM; on–off keyed or quantized; Data, telemetry, telecommand
|-
| F2D
| Angle modulation, straight FM; Digital, with modulation; Data, telemetry, telecommand
|-
| F3E
| Angle modulation, straight FM; Single analog channel; Telephony, voice, sound broadcasting
|-
| G3E
| Angle modulation, phase modulation; Single analog channel; Telephony, voice, sound broadcasting
|}
Permitted areas of operation
MURS operation is authorized anywhere a CB radio station is authorized and within or over any area of the world where radio services are regulated by the FCC. Those areas are within the territorial limits of:
- The fifty United States
- The District of Columbia
- American Samoa (seven islands)
- Baker Island
- Caribbean Insular areas
- Commonwealth of Northern Mariana Islands
- Commonwealth of Puerto Rico
- Guam Island
- Howland Island
- Jarvis Island
- Johnston Atoll (Islets East, Johnston, North and Sand)
- Kingman Reef
- Midway Atoll (Islets Eastern and Sand)
- Navassa Island
- Pacific Insular areas
- Palmyra Atoll (more than fifty islets)
- United States Virgin Islands (50 islets and cays)
- Wake Island
- Aboard any vessel of the United States, with the permission of the captain, while the vessel is traveling either domestically or in international waters
Restrictions
- Transmitter power output is limited to 2 watts.
- The highest point of any MURS antenna must not be more than above the ground or above the highest point of the structure to which it is mounted, whichever is higher.
Notable users
According to Bill Fawcett's Spaniel Journal, Spaniel pro-handler Dan Langhans was given a set of VHF business-band radios on the frequency of 154.57 MHz which became known by the trade as "blue dot" radios.
Costco Wholesale use Motorola DTR600, DLR1020, and Motorola Curve on Frequency 1 for general use among employees and Frequency 2 for communication with major sales departments. Walmart and Sam's Club use a Motorola Solutions model Motorola RDM2070D, which is exclusive to Walmart and Sam's Club. The Motorola RDM2070D is preprogrammed on MURS frequencies with most channels using CTCSS tone 21/4Z/136.5Hz.
See also
- Business band
- Family Radio Service
- General Mobile Radio Service
- Public Radio Service
- Unlicensed Personal Communications Services
References
External links
- FCC Wireless Services: MURS Home