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Motorola TA288 PMR446 licence-free radio Motorola TLKR T40 radio tuned to PMR channel 1. PMR446 (Private Mobile Radio, 446 MHz) is a licence-exempt service or UHF CB in the UHF radio frequency band, as personal radio service or citizens band radio, and is available for business and personal use in most countries throughout the European Union, [1] Malaysia, [2] and Singapore.
Digital DMR Tier I TDMA PMR446 channels are also available, eight channels from 446.10625 MHz to 446.19375 MHz with 12.5 kHz channel spacing steps. 4-level FSK modulation at 3.6 kbit/s is used. All three of the PMR446 channel plans occupy the same European-harmonized 446.0 MHz to 446.2 MHz frequency band.
The term PMR is often used by the public and magazine publishing to refer to the low power (500 milliwatt) PMR446 license exempt radio systems that consist of sixteen FM frequencies between 446.00625 and 446.19375 MHz for analog FM and thirty-two FDMA (digital) channels between 446.003125 and 446.196875 MHz. These are used for personal or ...
Many European countries use a similar 16–channel system near 446 MHz known as PMR446, as well as a 69–channel low-power LPD433 which is shared with the 433.92 MHz ISM band. GMRS equipment that is approved for use in the United States will not communicate with PMR446 radios due to using different frequency ranges.
In the Americas (defined as International Telecommunication Union (ITU) region 2), the FM broadcast band consists of 101 channels, each 200 kHz wide, in the frequency range from 87.8 to 108.0 MHz, with "center frequencies" running from 87.9 MHz to 107.9 MHz. For most purposes an FM station is associated with its center frequency.
In addition to radio frequencies used to connect handsets with cellular base stations, other parts of the radio spectrum are used to interconnect base stations and the wired telephone network. Some frequency bands may be vulnerable to interference by existing services in adjacent frequency bands, such as UHF television broadcasting.
A DMR Tier I radio would only use the PMR446 licence–free frequencies, and would have a maximum transmitted power of 0.5 watts as required by law for all PMR446 radios. [5] Although the DMR standard allows Tier I DMR radios to use continuous transmission mode, all known Tier I radios currently use TDMA, the same as Tier II.
The Private Land Mobile Radio Service (47CFR90, or Part 90 of the FCC Rules) was established in the US in 1927 [3] to permit commercial and public safety uses of two-way radio by commercial entities and non-Federal government agencies.