MURS

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Multi Use Radio Service

Short distance voice and data service for use by the general public for personal and business communications. Included in Part 95 of the FCC rules (Personal Radio Services) along with the more familiar services such as CB, FRS, GMRS, etc. Since it is a VHF CB service, MURS fills the gap between the UHF FM services (FRS/GMRS) and the original "Class D" HF AM/SSB 26-27 MHz CB service.

MURS is similar in function and intended use to the Freenet 149 MHz VHF CB service available in Germany and the "VHF 245" 245 MHz VHF CB service in Thailand, among other similar CB-like services worldwide.

Motorola RMM2050, a commonly used MURS handheld radio often found on construction sites, retail stores, and for similar purposes.


MURS Frequencies / Channels:

MURS Channel Identifier Frequency Maximum Bandwidth
MURS Channel 1 MURS-1 151.820 MHz 11.25 kHz (any mode - narrowband)
MURS Channel 2 MURS-2 151.880 MHz 11.25 kHz (any mode - narrowband)
MURS Channel 3 MURS-3 151.940 MHz 11.25 kHz (any mode - narrowband)
MURS Channel 4 Blue Dot MURS-4 154.570 MHz 20.00 kHz (any mode - wideband)
MURS Channel 5 Green Dot MURS-5 154.600 MHz 20.00 kHz (any mode - wideband)


Voice and data service for use by the general public. Personal, hobby and business uses permitted. All users must share frequencies. Repeaters and store-and-forward packet is prohibited. Per FCC rules, grandfathered users may operate higher power and/or repeater systems on these frequencies under the terms of their previous licenses.

Although FCC rules prohibit high power and repeater operations on the MURS frequencies, reports on various radio forums and by scanner listeners have indicated that hobbyists in certain areas are simplex repeaters, high power base stations, high power mobiles, and cross-band repeaters (often cross-band connected to GMRS or FRS frequencies) on the MURS frequencies. Just like hunters on VHF marine, the effective lack of FCC enforcement makes setting up and operating these systems quite attractive.

MURS has been adopted by many big box retailer stores such as Wal-Mart, Sam's Club, etc. Wal-Mart often uses these frequencies without CTCSS or DCS making interference a common issue.

MURS Regulations, Restrictions and other information

MURS is unique among the American (FCC Part 95) personal radio services (CB, FRS, GMRS, etc) in that AM, FM, and CW modes are allowed. F2D modulation and A2D modulation (digital using FM or digital using AM) are also permitted on the MURS frequencies. Voice inversion scrambling is permitted and offered as an option on radios such as the Motorola RMM2050 MURS portable radio. CTCSS and DCS are often used to facilitate frequency sharing. Because of the permissible data usage on the MURS frequencies, there are often data link networks heard on the MURS frequencies during VHF band openings.

Maximum transmitter output power is 2 watts. No limit on effective radiated power (ERP). Antenna height is limited in FCC rules and the highest point of the MURS antenna must not be more than 18.3 meters (60 feet) above the ground or 6.10 meters (20 feet) above the highest point of the structure on which it is mounted.

Maximum bandwidth on 151.8200 MHz, 151.8800 MHz and 151.9400 MHz is 11.25 kHz and maximum bandwidth on 154.5700 MHz and 154.6000 MHz is 20 kHz. No restriction on transmission mode as long as it meets the bandwidth requirement.

Repeaters are not allowed on the MURS frequencies per FCC rules. This includes duplex and simplex repeaters, also known as "store-and-forward" repeaters. This rule is apparently often ignored by MURS users as evidenced by the existence of simplex repeaters operating on the MURS frequencies as well as cross-band repeater setups using MURS (on VHF) and FRS/GMRS channels (on UHF). There are several reports on various radio hobbyist Internet forums of MURS repeaters including wide-area simplex repeaters located on mountaintops or in urban areas.

The 154 MHz frequencies were moved from the Business Radio Service (Part 90 of the FCC rules) and stations previously licensed to use these frequencies with higher power levels are considered grandfathered users and may legally transmit high power transmissions. Wal-Mart and other retailers using 154.600 MHz and 154.570 MHz have continued to use these frequencies after they were made license-free.



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