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PMR446

From Wikipedia, the free encyclopedia
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 in the UHF radio frequency band and is available for business and personal use in most countries throughout the European Union.[1]

PMR446 is typically used for small-site, same-building and line of sight outdoor activities. Equipment used ranges from consumer-grade to professional quality walkie-talkies (similar to those used for FRS/GMRS in the United States and Canada). Depending on surrounding terrain range can vary from a few hundred metres (in a city) to a few kilometres (flat countryside) to many kilometres from high ground.

Historically, analogue FM is used but a digital voice mode has been available in radios conforming to digital private mobile radio (dPMR446) and digital mobile radio (DMR Tier 1) standards designed by ETSI.

Originally 8 channels were available in analogue mode but this has now been increased to 16 channels. Typically PMR446 is used for both recreational and business use, additionally it has been utilized by amateur-radio operators and radio enthusiasts as a license-free experimental band.

History

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The first steps towards creating licence-free short range radio communications were taken in April 1997 when the European Radio Communications Committee decided on a 446 MHz frequency band to be used for the new radios. In November 1998, ERC Decision (98)25 allocated frequency band 446.0–446.1 MHz for analogue PMR446; another two decisions established licence exemption for PMR446 equipment and free circulation of the PMR446 equipment. The first country which introduced these frequencies for licence-free use was Ireland on 1 April 1998. The United Kingdom introduced PMR446 service in April 1999; since 2003, it has replaced the former short-range business radio (SRBR) service.

In October 2005, ECC Decision (05)02 added unlicensed band 446.1–446.2 MHz for use by digital DMR/dPMR equipment.

In July 2015, ECC Decision (15)05 doubled the number of analog channels to 16 by extending analog operation onto the 446.1–446.2 MHz band previously used by digital DMR/dPMR equipment, effective January 2016; from January 2018, the number of digital channels was doubled by extending onto the 446.0–446.1 MHz band used by analog FM.

Range

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Until recently, PMR446 radios were handheld transceivers with fixed antennas (see Technical information). In November 2015, Midland Radio announced the release of the GB1 mobile PMR446 radio for vehicular use.[2][3][4]

The range of PMR446, just like any VHF or UHF radio, is dependent on many factors like environment (in-city range is far less than in an open field), height above surrounding obstructions, and, to a lesser extent, weather conditions. The antenna type and location, transmit power and receive sensitivity also affect range. However, with PMR446 most of these variables are fixed at manufacturing to comply with the PMR446 specifications. Most of the time the maximum range that a user in a city can expect is a few hundred metres or less.

Range may be many kilometres, for example between hilltops, or only a few hundred metres, if for example a hill or large metal object is in the transmission path between radios. The best known long-distance record is 333 mi (536 km) from Blyth in the United Kingdom to Almere, Netherlands.[5] This was the result of enhanced propagation conditions, not a line-of-sight signal.

Use worldwide

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PMR446 radios use frequencies that in Australia, the U.S., and Canada are allocated to amateur radio operators, and military radar systems.[6]

Instead, the U.S., Canada and Mexico use the Family Radio Service (FRS) system, which provides a similar service on different frequencies, around 462 and 467 MHz. These frequencies are allocated to the emergency services in Europe, notably the fire brigade in the UK, police in Russia and commercial users in Australia.[7] Interference with licensed radio services may result in prosecution.

Australia, New Zealand, Vanuatu and Malaysia use the UHF Citizen's Band system in the 476–477 MHz range and a maximum power output of 5 W giving improved range over the lower power PMR system.

PMR446-compliant equipment may be used anywhere throughout Europe.[8]

Type approved PMR446 radios with power up to 500 mW can be used without any licence in India[9] and Vietnam.[10] The devices may not be base stations or repeaters, and must use integrated antennas only.

Technical information

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PMR446 covers band 446.0–446.2 MHz. The general ECC decision[11] however still requires integral antennas and the actual implementation varies between different countries.

Analogue FM and digital TDMA

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Kenwood TK3301 and TK3501 PMR446 radios

Analogue PMR446 uses 16 FM channels separated by 12.5 kHz from each other. Maximum power is 500 mW ERP and equipment must be used on a mobile basis. CTCSS is usually used, with more upmarket models also featuring DCS and/or fixed-carrier voice inversion. Before January 2016, only the lower 8 channels were allowed for analog FM operation.[citation needed]

For those older PMR446 radios with 38 codes, the codes 0 to 38 are CTCSS Tones:

PMR446 CTCSS Privacy Codes
Code Tone Hz Code Tone Hz Code Tone Hz
0 Off 13   103.5 26   162.2
1     67.0 14   107.2 27   167.9
2     71.9 15   110.9 28   173.8
3     74.4 16   114.8 29   179.9
4     77.0 17   118.8 30   186.2
5     79.7 18   123.0 31   192.8
6     82.5 19   127.3 32   203.5
7     85.4 20   131.8 33   210.7
8     88.5 21   136.5 34   218.1
9     91.5 22   141.3 35   225.7
10     94.8 23   146.2 36   233.6
11     97.4 24   151.4 37   241.8
12   100.0 25   156.7 38   250.3


For those newer PMR446 radios with 121 codes, codes 0 to 38 are as above while codes 39 to 121 are DCS codes:

DCS
Code DCS Code DCS Code DCS
39 023 67 174 95 445
40 025 68 205 96 464
41 026 69 223 97 465
42 031 70 226 98 466
43 032 71 243 99 503
44 043 72 244 100 506
45 047 73 245 101 516
46 051 74 251 102 532
47 054 75 261 103 546
48 065 76 263 104 565
49 071 77 265 105 606
50 072 78 271 106 612
51 073 79 306 107 624
52 074 80 311 108 627
53 114 81 315 109 631
54 115 82 331 110 632
55 116 83 343 111 654
56 125 84 346 112 662
57 131 85 351 113 664
58 132 86 364 114 703
59 134 87 365 115 712
60 143 88 371 116 723
61 152 89 411 117 731
62 155 90 412 118 732
63 156 91 413 119 734
64 162 92 423 120 743
65 165 93 431 121 754
66 172 94 432

Digital PMR446 DMR Tier I (TDMA) uses 16 digital voice channels separated by 12.5 kHz from each other with 4-level FSK modulation at 3.6 kbit/s.[12] Before January 2018, only the higher 8 channels were allowed for digital TDMA operation.

Some Digital PMR446 radios (Hytera BD305LF, Retevis RT40, ...) support Dual Capacity Direct Mode (DCDM), which allows for the use of two timeslots during simplex (radio-to-radio) communication. This effectively doubles the channel capacity by allowing two simultaneous transmissions on one channel.[13]

Color Code (0 to 16) is the equivalent of CTCSS for digital. It's used to isolate a population of users (a company, an association, a family, ...).

By convention CC1 is used for public contact.

TalkGroups are used to separate groups of users (ex: TG1 for direction and TG2 for room service in a hotel using channel 12 CC7).

By contacting a specific TG, each user subscribing to this TG will hear you (Group Call).

A user can subscribe to many TGs (RX Group List).

It is also possible to contact all users in your color code (All Call).

Radio ID One for each user, to be contacted directly (Private Call).

Analogue (NFM) and digital TDMA (DMR)[14]
Channel Frequency (MHz) Channel Spacing (kHz) Channel Spacing

Known As

Comments (Channel/CTCSS)
1 446.00625 12.5 Narrow [NFM] FM: Emergency communication (1/12)

FM: Trucker (1/9)

FM: Baby monitor (1/0)

FM: Children's channel (1/10)

2 446.01875 12.5 Narrow [NFM] FM: Geocaching

FM: Camping

FM: Mountain (German-speaking countries)[15]

3 446.03125 12.5 Narrow [NFM] FM: Prepper Channel (3/1), in disasters

FM: Bicycle, Mountain bike

FM: Mountain (Poland) (3/14)

4 446.04375 12.5 Narrow [NFM] FM: Drone-Pilot Intercom (4/14)

FM: 4WD (4/4)

FM: Boat (4/16)

5 446.05625 12.5 Narrow [NFM] FM: Scouts (5/5)
6 446.06875 12.5 Narrow [NFM] FM: Event Channel [16]

FM: Hunters (6/12)

FM: Fisherman

FM: Inland sailing (Poland) (6/16)

FM: Free Radio Network (6/20)

7 446.08125 12.5 Narrow [NFM] FM: Mountain (7/7). Mountaineers in Spain propose using channel 7 subtone 7 for mountain safety.[17]
8 446.09375 12.5 Narrow [NFM] FM: DX & Calling Channel (8/8)

FM: Distress, European emergency channel

FM: Mountain - Hill Walking Radio Network (Ireland) (8)

FM: Mountain (Italy) [18] (8/16)

9 446.10625 12.5 Narrow [NFM] DMR: Digital Calling Channel (CC1 TG99)

DMR: Distress (CC1 TG9112), EmCOMM other channel with same TG

FM: AIRSOFT

10 446.11875 12.5 Narrow [NFM] FM: Fox Hunting, A.R.D.F.
11 446.13125 12.5 Narrow [NFM]
12 446.14375 12.5 Narrow [NFM]
13 446.15625 12.5 Narrow [NFM]
14 446.16875 12.5 Narrow [NFM]
15 446.18125 12.5 Narrow [NFM]
16 446.19375 12.5 Narrow [NFM]

Digital FDMA

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Digital PMR446 dPMR (FDMA) uses 32 digital voice channels separated by 6.25 kHz from each other with 4-level FSK modulation at 3.6 kbit/s.[19] Before January 2018, only the upper 16 channels were allowed for digital FDMA operation.

Digital FDMA (dPMR446)[14]
Channel Frequency (MHz) Channel Spacing (kHz) Comments
1 446.003125 6.25
2 446.009375 6.25
3 446.015625 6.25
4 446.021875 6.25
5 446.028125 6.25
6 446.034375 6.25
7 446.040625 6.25
8 446.046875 6.25
9 446.053125 6.25
10 446.059375 6.25
11 446.065625 6.25
12 446.071875 6.25
13 446.078125 6.25
14 446.084375 6.25
15 446.090625 6.25
16 446.096875 6.25
17 446.103125 6.25
18 446.109375 6.25
19 446.115625 6.25 dPMR => Calling Channel (CC1 TG99)

dPMR => Mutual assistance (CC1 TG9112)

20 446.121875 6.25
21 446.128125 6.25
22 446.134375 6.25
23 446.140625 6.25
24 446.146875 6.25
25 446.153125 6.25
26 446.159375 6.25
27 446.165625 6.25
28 446.171875 6.25
29 446.178125 6.25
30 446.184375 6.25
31 446.190625 6.25
32 446.196875 6.25

PMR446 gateways

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Recently some users have implemented the simplex repeater system, a cheap and easy way to extend the radio range by using extra radios connected to a small repeater controller. This is also known as "Parrot", "ATX-2000" or just "Echo Repeater" after how it sounds repeating every transmission it receives.[20]

PMR446 gateways extend the range of PMR446. These gateways are connected through internet using a client/server VoIP system such as eQSO or the Free Radio Network (FRN).

Law

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See also

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References

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  1. ^ "Analogue and Digital PMR446 Information Sheet" (PDF). Ofcom. Retrieved 2013-10-03.
  2. ^ World First Midland GB1 PMR 446 Mobile Attached Antenna
  3. ^ Midland GB1 First Look Midland GB1 Mobile PMR446 - Manual Download Includes Specs
  4. ^ Midland GB1 First Look *Updated With English Manual*
  5. ^ "Delboy's DX Contact UK to Amsterdam". Delboy Enterprises. 5 August 2003. Archived from the original on 2008-02-09.
  6. ^ "420-450 MHz" (PDF). National Telecommunications and Information Administration. March 1, 2014. Retrieved July 23, 2019. The band 420-450 MHz is used extensively by the military agencies for land-based, shipborne, and airborne radar systems to perform important national security functions.
  7. ^ "Can I bring my FRS / GMRS Radio to Europe - Austria, Germany, Switzerland : British Expat Discussion Forum". Britishexpats.com. 2005-05-10. Retrieved 2010-11-18.
  8. ^ "CEPT ECC Decision (15)05". cept.org. 2018-02-03. Retrieved 2023-10-03.
  9. ^ "Wireless Planning and Coordination Wing Notification G.S.R. 1047(E)" (PDF). The Gazette of India. 2018-10-18. Retrieved 2020-01-03.
  10. ^ Ministry Of Information And Communications, Socialist Republic Of Vietnam. No. 46 /2016/TT-BTTTT, Circular, Regulation on the list of radio devices exempted from frequency license, together with their technical and operational conditions. Annex 2, Authorized Frequency Bands And Emission Level. Annex 18, Technical And Operation Conditions For Low-Power Radio Communication Device.
  11. ^ ECC Decision (15)05 (PDF) (Technical report). 3 July 2015. Archived from the original (PDF) on 19 August 2017. Retrieved 21 July 2015.
  12. ^ "PMR446 Frequencies - Analogue and Digital". Homepage.ntlworld.com. Archived from the original on 2008-05-28. Retrieved 2010-11-18.{{cite web}}: CS1 maint: bot: original URL status unknown (link)
  13. ^ "Mototrbo Simple Connection & Direct Mode". www.mototrbo.sk. Retrieved 2021-12-11.
  14. ^ a b "A guide to the new PMR446 licence-free radio frequencies following ECC Decision (15)05 and what it means to you" (PDF). Kenwood Communications. August 2016. Retrieved 2019-09-21.
  15. ^ "Funk im Outdooreinsatz". Deutscher Alpenverein. Retrieved 2020-11-13. Es gibt im PMR-Funk einen „Bergsteigerkanal" der sich etabliert hat (Kanal 2: Bergsteiger- und Geocachingkanal).
  16. ^ "Bandplan 433 MHz". docs.google.com (in German). Retrieved 29 July 2022.
  17. ^ "Iniciativa Canal 7-7". www.canal77pmr.com (in Spanish). Retrieved 7 January 2021.
  18. ^ "Rete Radio Montana". www.reteradiomontana.it (in Italian). Retrieved 5 September 2024.
  19. ^ "dPMR: A low cost digital successor to PMR446 is on the Horizon". Cmlmicro.com. Archived from the original on 2011-09-27. Retrieved 2010-11-18.
  20. ^ Sowden, Dave (2012-10-07). "RADIO PIXIE: PMR446 Parrot Repeater". RADIO PIXIE. Retrieved 2019-10-20.
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