MURS

From Free Knowledge Base- The DUCK Project: information for everyone
Jump to: navigation, search

Multi-Use Radio Service (MURS) is an unlicensed two-way radio service similar to Citizens Band (CB). These radios may have a maximum legal output of 2 watts. The highest point of any MURS antenna must not be more than 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. It is short distance voice and data service for use by the general public for personal and business communications.

  • FCC License: No
  • Max Output: 2 watts
  • Frequency: 2 meter

MURS comprises the following five frequencies:

Channel   Frequency      Bandwidth 	Channel Name
1 	   151.820 MHz 	  11.25 kHz 	N/A 
2 	   151.880 MHz 	  11.25 kHz 	N/A
3 	   151.940 MHz 	  11.25 kHz 	N/A
4 	   154.570 MHz 	  20.00 kHz 	Blue Dot  (used by many businesses)
5 	   154.600 MHz 	  20.00 kHz 	Green Dot  (used by many businesses)

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

The two channels in the 154Mhz range can be operated in wide band 25khz while the first three are restricted to narrow band 12.5khz only.

Digital voice modulation like MotoTRBO and P25 can be used legally on the MURS frequencies provided their emission bandwidth is less than or equal to the 11.25 kHz (for the 151 MHz frequencies) or the 20 kHz (for the 154 MHz frequencies) bandwidth restrictions. Repeaters are not allowed on the MURS frequencies.

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. Only the Blue Dot (154.57 MHz) and Green Dot (154.6 MHz) channels are license free and part of MURS. The other color dot frequencies require FCC Part 90 Business Radio licenses to operate on. You must have a license to use 151.625 MHz, 151.955 MHz, 467.925 MHz, 467.850 MHz, 467.7625 MHz, 464.500 MHz and 464.550 MHz.

Companies that offer radios advertised capable of MURS and GMRS do not seem to be legal even if the company claims otherwise.

  • §95.2761 MURS transmitter certification. (c) A grant of equipment certification will not be issued for MURS transmitters capable of operating under both this subpart (MURS) and under any other subparts of this chapter (except part 15).
  • §95.1761 GMRS transmitter certification. (c) No GMRS transmitter will be certified for use in the GMRS if it is equipped with a frequency capability not listed in §95.1763, unless such transmitter is also certified for use in another radio service for which the frequency is authorized and for which certification is also required. No GMRS transmitter will be certified for use in the GMRS if it is equipped with the capabilities to operate in services that do not require equipment certification, such as the Amateur Radio Service. All frequency determining circuitry (including crystals) and programming controls in each GMRS transmitter must be internal to the transmitter and must not be accessible from the exterior of the transmitter operating panel or from the exterior of the transmitter enclosure.


Related

See also: