Multi-Use Radio Service Basics and Regulations

The Multi-Use Radio Service (MURS) is a great way to stay connected, especially in areas with limited cell phone coverage. MURS devices operate on six frequencies, 151.820 MHz, 154.570 MHz, 154.600 MHz, 154.570 MHz, 154.600 MHz, and 154.570 MHz, which are shared with other MURS users.

MURS devices are relatively easy to use and require minimal setup. They're perfect for outdoor enthusiasts, farmers, and small business owners who need to stay in touch with their teams.

The Federal Communications Commission (FCC) regulates MURS devices to ensure they operate within specific guidelines. The FCC requires MURS devices to operate on the designated frequencies and power levels to avoid interference with other communication devices.

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The Multi-Use Radio Service (MURS) is a two-way, short distance voice or data communication service for facilitating personal or business activities of the general public, as defined by the FCC.

MURS operates in the VHF band between 151 and 154 MHz, making it particularly useful for rural and outdoor settings where the lower frequencies can bend around hills and penetrate through trees and foliage.

The MURS band is also known for its ability to allow external antennas and up to 2 Watts of power for handheld radios, greatly increasing the potential operating range.

Here's a breakdown of the MURS channels, frequencies, and power limits:

Unlike the FRS band, which has very low power limits, MURS allows for more flexibility and range with its higher power limits and external antenna capabilities.

The MURS band is largely unused, making it a great choice for serious recreational, prepper, or SHTF emergency communications.

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As you start using a MURS device, it's essential to understand the regulations and restrictions in place.

Transmitter power output is limited to 2 watts, so be mindful of your device's settings.

The highest point of any MURS antenna must not exceed 18.3 meters (60 feet) above the ground or 6.10 meters (20.0 feet) above the highest point of the structure to which it is mounted, whichever is higher.

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This means you should carefully consider the placement of your antenna to avoid any potential issues.

Transmitting on MURS frequencies is not allowed while aboard aircraft in flight, so make sure to turn off your device before taking off.

Devices that use MURS must be specially labeled and certified, so double-check your device's credentials before using it.

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Many manufacturers have made MURS-exclusive radios, such as the Motorola CP100m and RDM2080D, which are restricted to the 5 MURS frequencies and 2W output power.

These radios can be used without an FCC license, making them a convenient option for businesses.

Some popular MURS-exclusive radios include the Motorola RMM2050, which is currently available.

These radios are designed to work seamlessly with other MURS devices, allowing for easy communication and coordination.

MURS devices offer a wide range of products that can be used in various settings.

MURS devices include wireless base station intercoms, handheld two-way radios, wireless dog training collars, wireless public address units, customer service callboxes, wireless remote switches, and wireless callboxes with or without gate opening ability.

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Most MURS devices are compatible with each other because they use standard frequencies.

However, analog two-way radios may require matching CTCSS or DCS tones to work together, which can usually be done via basic programming supported by most MURS two-way radios.

The goTenna is a digital radio product that operates on the MURS band and pairs with smartphones to enable users to send texts and share locations on a peer-to-peer basis.

The goTenna is not interoperable with other MURS devices, even though they operate on the same spectrum, employing "listen-before-talk" to reduce interference in the band's five channels.

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Business Radios are a convenient option for businesses that need to stay in touch with their teams.

Many manufacturers make MURS-exclusve radios, which are restricted to the 5 MURS frequencies and can be used without an FCC license.

The Motorola CP100m, RDM2080D, and RMM2050 are examples of MURS-exclusive radios made by Motorola Solutions.

The RDM2070D and RDM2080D were previously used by Walmart and Sam's Club, but they are now cancelled in favor of the RMM2050.

The RMM2050 is a versatile radio that can be used on MURS frequencies and is available to anyone.

Businesses can also use freely programmable two way radios on the MURS channels, which are pre-defined frequencies in the middle of the VHF business band.

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You can replace a damaged antenna with another one of the same or a compatible similar type. This is a straightforward process that won't require any special expertise.

If you need to replace the batteries in your MURS transmitter, you can use batteries of a type specified by the manufacturer. This ensures that the replacement batteries meet the necessary safety and performance standards.

The MURS (Multi-Use Radio Service) band has specific bandwidth requirements that your transmitter must meet. Each channel has its own unique bandwidth limitation.

On channels 151.820, 151.880, and 151.940 MHz, the occupied bandwidth of emissions must not exceed 11.25 kHz.

For channels 154.570 and 154.600 MHz, the occupied bandwidth of emissions must not exceed 20.0 kHz.

Type A3E emissions, used on some MURS channels, have an even stricter requirement, with an occupied bandwidth of no more than 8.0 kHz.

Here's a summary of the authorized bandwidths for MURS channels:

MURS stations that were licensed before November 13, 2000, are allowed to continue operating under the same terms as before.

These stations must meet the antenna height requirements, which state that the highest point of the antenna must not be more than 18.3 meters (60 feet) above the ground or 6.10 meters (20 feet) above the structure on which it is mounted.

You can replace a damaged MURS antenna with another one of the same or a compatible similar type.

Batteries in your MURS transmitter can be replaced with batteries specified by the manufacturer.

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MURS station operators must take reasonable precautions to avoid causing harmful interference, including monitoring the transmitting frequency for communications in progress before transmitting.

To minimize interference, MURS transmitters must only transmit specific emission types, such as A1D, A2B, A2D, A3E, F2B, F1D, F2D, F3E, and G3E. Emission types like A3E, F3E, and G3E may include selective calling or tone-operated squelch tones to establish or continue voice communications.

MURS transmitters are prohibited from transmitting in the continuous carrier mode, which can cause significant interference.

The power of unwanted emissions must be attenuated below the transmitter output power in Watts (P) by at least 7.27(fd−2.88 kHz) dB on any frequency removed from the channel center frequency by a displacement frequency (fd in kHz) that is more than 5.625 kHz, but not more than 12.5 kHz.

The attenuation requirements for unwanted emissions vary depending on the frequency displacement. For example, on any frequency removed from the channel center frequency by more than 10 kHz, but not more than 20 kHz, the power of unwanted emissions must be attenuated by at least 25 dB.

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Here are the attenuation requirements for unwanted emissions:

Each MURS transmitter type must be designed such that the transmitter power output does not exceed 2 Watts under normal operating conditions.

You can use a MURS station to transmit voice, data, or image signals. This gives you a lot of flexibility in how you use your radio.

MURS stations can also be used for telecommand and telemetry functions, which is useful for controlling devices or tracking data remotely.

One thing you shouldn't do with a MURS station is use it as a repeater station or signal booster. This includes store-and-forward packet operation, which is a way of relaying signals through a network.

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Multi-Use Radio Service (MURS) transmitters must be designed to meet specific frequency tolerance and stability requirements. Each MURS transmitter type must be designed such that the carrier frequencies remain within ±2.0 parts-per-million (ppm) of the channel center frequencies specified in § 95.2763 during normal operating conditions for emission bandwidths of 6.25 kHz or less.

MURS transmitters must also be certified in accordance with this subpart and part 2 of this chapter. A grant of equipment certification will not be issued for any MURS transmitter type that fails to comply with all of the applicable rules in this subpart.

The transmitting power limit for MURS transmitters is 2 Watts under normal operating conditions. Each MURS transmitter type must be designed such that the transmitter power output does not exceed 2 Watts under normal operating conditions.

Here are the unwanted emissions limits for MURS transmitters, categorized by channel center frequencies:

MURS transmitters must be designed to meet specific frequency tolerance and stability requirements.

Each MURS transmitter type must be designed to meet the applicable frequency tolerance and stability requirements of this section. MURS transmitters that operate with an emission bandwidth of 6.25 kHz or less must be designed such that the carrier frequencies remain within ±2.0 parts-per-million (ppm) of the channel center frequencies specified in § 95.2763 during normal operating conditions.

The five VHF channels allotted for shared use in the MURS are designated by their center frequencies in megahertz: 151.820, 151.880, 151.940, 154.570, and 154.600 MHz.

Each MURS transmitter type must be certified in accordance with this subpart and part 2 of this chapter. A grant of equipment certification will not be issued for any MURS transmitter type that fails to comply with all of the applicable rules in this subpart.

MURS transmitters must be designed such that the transmitter power output does not exceed 2 Watts under normal operating conditions.

MURS range will vary, depending on antenna size and placement. With an external antenna, ranges of 10 miles (16 km) or more can be expected.

MURS stations are prohibited from interconnection with the public switched network.

Interconnection is defined as connection through automatic or manual means of multi-use radio stations with the facilities of the public switched telephone network to permit the transmission of messages or signals between points in the wireline or radio network of a public telephone company and persons served by multi-use radio stations.

Wireline or radio circuits or links furnished by common carriers for transmitter control or as an integral part of an authorized, private, internal system of communication are not considered to be interconnection for purposes of this rule part.

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The audio filter is a crucial component in MURS transmitters, and it plays a significant role in meeting the unwanted emissions limits.

To be specific, the audio filter must be located between the modulation limiter and the modulated stage of the transmitter.

The audio filter's attenuation requirements are quite strict, especially in the frequency range of 3 to 15 kHz. In this range, the filter must have an attenuation of at least 40 log (f/3) dB more than the attenuation at 1 kHz.

Above 15 kHz, the filter's attenuation must be at least 28 dB more than the attenuation at 1 kHz.

Here's a summary of the audio filter's attenuation requirements in a table:

These requirements are essential to ensure that the MURS transmitter meets the unwanted emissions limits and operates within the specified frequency bands.