PMR-446 info

What are licence free walkie-talkies?

They are known as PMR-446 radios and they work between the frequency band 446.0 - 446.1 MHz. They used to have a Max transmit power of 500mW, and an approximated range of 5 km in optimal conditions.

The PMR (Private Mobile Radio) 446 service has been introduced following the adoption by the CEPT/ERC1 of the Decisions ERC/DEC/(98) 25, 26 and 27 which comply member states to:

a) Set aside the band 446.0 - 446.1 MHz for a PMR 446 service, with a channel plan based on 12,5kHz spacing:

F1 = 446,00625 MHz.
F2 = 446,01875 MHz.
F3 = 446,03125 MHz.
F4 = 446,04375 MHz.
F5 = 446,05625 MHz.
F6 = 446,06875 MHz.
F7 = 446,08125 MHz.
F8 = 446,09375 MHz.

b) Users do not require a licence to use PMR 446 radios.

c) Allow the free circulation and use of PMR 446 equipment using frequencies in the 446.0 - 446.1 MHz band and complying with the European technical standard ETS 300 296.

d) The equipment shall use only integral antenna and an effective radiated power not exceeding 500mW.

This use has the consideration of common use.

It is used mainly for commercial or recreational activities, being able to enjoy economic, fast, trustworthy, simple and practical a communication.

It is the most reasonable way to remain in constant contact since license is not needed to use this portable equipment, that can be taken to any part.

The following accessories can be used with PMR 446 radios: external microphones including VOX type microphones; earphones, headphones and external loudspeakers; and DC power sockets, charge sockets and battery packs.

The accessories must be connected by appropriate sockets installed by the manufacturer at the time of manufacture and conformance evaluation and their use must not affect the RF characteristics of the radios.

In all cases, the use of these facilities must not cause any change to, or effect on, the performance characteristics of the PMR 446 radio, as permitted under the Wireless Telegraphy (Exemption) Regulations (SI 1999/930).

Differencies between Professional or Domestic use.

The more appreciable difference is the aspect, the Domestic ones are smaller, look less robust and are cheaper. The Professionals, as its name suggests, are special for work, it used to be solid equipments, even some of them are water resistant, and even though have the same power its performance is better, therefore have a better range with better quality, of course that have a cost and that's why are more expensive. Its range can be between 800m and 5km depending on the terrain and conditions, it's not the same communicate on the sea where the range can be more than 5km than surrounding buildings where the range probably will be less than 1km.

Advantages:

- It is not required to contract any type of licence.
- It does not have call costs, as it happens with mobile phones.
- You do not have to pay any monthly payment.
- They are very easy to use.
- Instantaneous communication, it is not necessary any protocol to communicate.

Applications:

FOR BUSINESS
- Intercom between floors
- Communication vehicle to vehicle
- In the warehouse
- Within the factory
- In car park
- In construction industry
- Trade Shows
- Restaurants
- Use between professionals like electricians, painters...
- Airports
- Railway stations
- Bus stations

SECURITY / EMERGENCY
- Shopping centers
- Rescue / fire operations...
- Nature Parks

DAILY USE
- Shopping
- At home

LEISURE TIME
- Sport events
- Hiking
- Climbing
- Trekking
- Cycling
- Camping
- Holidays
- Mountain bike trips
- Skiing
- In the golf course
- Playing Paintball

PMR-446 Frequently Asked Questions

What are the DCS codes?

The DCS (Digital-Coded Squelch) codes are identical to the analogical ones, the only difference its on the modulation and the way of implementing, there are a lot of digital codes but just like the analogical there are 104 codes determined as standards.

The PMR-446 LPD 443 or LPD 860 radios not usually include them, there are some exceptions that are the semi-professionals and professionals as the DCS codes are necessary for a professional use, just imagine a crane controller that tries to talk with other workers and because of not having digital codes has to be hearing other stations in the same channel impeding the communication.
As a general rule used to discriminate interferences better than analogical codes.

To enter the PMR-446 LPD 443 or LPD 860 relay stations is necessary to previously know which digital code is being used, otherwise they will not heard us.

DCS	Freq	DCS	Freq	DCS	Freq	DCS	Freq	DCS	Freq	DCS	Freq	DCS	Freq	DCS	Freq	DCS	Freq
001	023	013	071	025	143	037	225	049	266	061	356	073	452	085	532	097	703
002	025	014	072	026	145	038	226	050	271	062	364	074	454	086	546	098	712
003	026	015	073	027	152	039	243	051	274	063	365	075	455	087	565	099	723
004	031	016	074	028	155	040	244	052	306	064	371	076	462	088	606	100	731
005	032	017	114	029	156	041	245	053	311	065	411	077	464	089	612	101	732
006	036	018	115	030	162	042	246	054	315	066	421	078	465	090	624	102	734
007	043	019	116	031	165	043	251	055	325	067	413	079	466	091	627	103	743
008	047	020	122	032	172	044	252	056	331	068	423	080	503	092	631	104	754
009	051	021	125	033	174	045	255	057	332	069	431	081	506	093	632	-	-
010	053	022	131	034	205	046	261	058	343	070	432	082	516	094	654	-	-
011	054	023	132	035	212	047	263	059	346	071	445	083	523	095	662	-	-
012	065	024	134	036	223	048	265	060	351	072	446	084	526	096	664	-	-

What are the CTCSS tones?

Those are the 38 analogical standard tones used by the PMR-446 LPD 443 or LPD 860 radios, a sub-audible audio tone is emitted and that's how the receiver can distinguish which signals pass or not depending on the assigned code. (To permit receiving all the signals in some radios it's possible to select the 00 code).

To enter the PMR-446 LPD 443 or LPD 860 relay stations is necessary to previously know which analogical tone is being used, otherwise they will not heard us.

Tono	Frecuencia	Tono	Frecuencia	Tono	Frecuencia	Tono	Frecuencia	Tono	Frecuencia
01	67.0 Hz	09	91.5 Hz	17	118.8 Hz	25	156.7Hz	33	210.7 Hz
02	71.9 Hz	10	94.8 Hz	18	123.0 Hz	26	162.2 Hz	34	218.1 Hz
03	74.4 Hz	11	97.4 Hz	19	127.3 Hz	27	167.9 Hz	35	225.7 Hz
04	77.0 Hz	12	100.0 Hz	20	131.8 Hz	28	173.8 Hz	36	233.6 Hz
05	79.7 Hz	13	103.5 Hz	21	136.5 Hz	29	179.9 Hz	37	241.8 Hz
06	82.5Hz	14	107.2 Hz	22	141.3 Hz	30	186.2 Hz	38	250.3 Hz
07	85.4 Hz	15	110.9 Hz	23	146.2 Hz	31	192.8 Hz	-	-
08	88.5 Hz	16	114.8 Hz	24	151.4 Hz	32	203.5 Hz	-	-