Radio: services and frequencies

When phones are down, radio still works. Which radio you may use, and on which channels, depends on the service and your licence.

Legal notes first (United States).

CB, FRS and MURS need no licence. GMRS needs an FCC licence. Amateur (ham) radio needs an FCC licence and an exam.

Use only radios certified for the service. A Baofeng or other ham radio transmitting on FRS or GMRS channels is not legal: those channels need Part 95-certified radios.

In an emergency, FCC rules (47 CFR 97.403) let a licensed amateur station use any means of radio communication at its disposal for essential communications about the immediate safety of human life or protection of property, when normal communication systems are not available. This is not a general permission for unlicensed transmitting.

Other countries have different bands and rules. Check before you transmit.

Which radio for what

Service	Licence	Typical range	Best for
CB (27 MHz)	None	1 to 5 miles; much more with skip	Vehicles, highways, rural
FRS (462/467 MHz)	None	0.5 to 2 miles	Family, short range
GMRS (462/467 MHz)	FCC licence, no exam	1 to 5 miles; 20+ with repeaters	Family groups, repeaters
MURS (151/154 MHz)	None	1 to 3 miles	Farms, property, groups
Ham 2 m / 70 cm	FCC licence and exam	1 to 5 miles; 50+ via repeaters	Emergency nets, long range
NOAA Weather Radio	Receive only	Up to about 40 miles	Weather and hazard alerts
Marine VHF	Boats; none for recreational use in US waters	5 to 25 miles over water	Boats, Coast Guard

Range depends far more on antenna height and terrain than on power. Climb high.

CB radio

40 channels, 26.965 to 27.405 MHz. Up to 4 watts carrier on AM, 12 watts PEP on single sideband (SSB). No licence needed.

Channel 9: emergencies and traveller assistance only.
Channel 19: highway and trucker channel, informally.

Ch	MHz	Ch	MHz	Ch	MHz	Ch	MHz
1	26.965	11	27.085	21	27.215	31	27.315
2	26.975	12	27.105	22	27.225	32	27.325
3	26.985	13	27.115	23	27.255	33	27.335
4	27.005	14	27.125	24	27.235	34	27.345
5	27.015	15	27.135	25	27.245	35	27.355
6	27.025	16	27.155	26	27.265	36	27.365
7	27.035	17	27.165	27	27.275	37	27.375
8	27.055	18	27.175	28	27.285	38	27.385
9	27.065	19	27.185	29	27.295	39	27.395
10	27.075	20	27.205	30	27.305	40	27.405

Channel 23 sits out of order (27.255) for historical reasons. SSB users conventionally gather on channels 36 to 40.

Antenna basics: a full-size whip (about 102 inches) works best; shorter loaded antennas are easier on vehicles. Mount it high and centred, with a good ground plane, and tune it with an SWR meter (aim for under 2:1).

Common 10-codes: 10-4 (understood), 10-9 (repeat), 10-20 (location), 10-33 (emergency traffic), 10-36 (correct time). Plain language is clearer in an emergency.

FRS and GMRS

22 shared channels. FRS radios need no licence; GMRS needs an FCC licence (currently a $35 fee, valid 10 years, no exam, and it covers your immediate family).

Ch	MHz	FRS max power	GMRS max power
1	462.5625	2 W	5 W
2	462.5875	2 W	5 W
3	462.6125	2 W	5 W
4	462.6375	2 W	5 W
5	462.6625	2 W	5 W
6	462.6875	2 W	5 W
7	462.7125	2 W	5 W
8	467.5625	0.5 W	0.5 W
9	467.5875	0.5 W	0.5 W
10	467.6125	0.5 W	0.5 W
11	467.6375	0.5 W	0.5 W
12	467.6625	0.5 W	0.5 W
13	467.6875	0.5 W	0.5 W
14	467.7125	0.5 W	0.5 W
15	462.5500	2 W	50 W
16	462.5750	2 W	50 W
17	462.6000	2 W	50 W
18	462.6250	2 W	50 W
19	462.6500	2 W	50 W
20	462.6750	2 W	50 W
21	462.7000	2 W	50 W
22	462.7250	2 W	50 W

GMRS repeaters listen 5 MHz higher (467.550 to 467.725 MHz) on channels 15R to 22R and retransmit on the matching 462 MHz channel, often from a hilltop. Many need a CTCSS tone; ask the owner. FRS radios may not use repeaters (see the FCC FRS page below).

"Privacy codes" (CTCSS or DCS tones) do not make a channel private. They only mute other users' traffic on your radio.

MURS

Five channels, no licence, up to 2 watts. Quieter than FRS in most areas.

Ch	MHz	Bandwidth
1	151.820	Narrow (11.25 kHz)
2	151.880	Narrow (11.25 kHz)
3	151.940	Narrow (11.25 kHz)
4	154.570	Wide (20 kHz)
5	154.600	Wide (20 kHz)

Amateur (ham) radio

The Technician licence opens the 2-metre and 70-centimetre bands, the backbone of local emergency radio. It takes a 35-question multiple-choice exam given by volunteer examiners; the FCC charges a $35 application fee and the licence lasts 10 years.

Band	Range	National simplex calling frequency
2 m	144 to 148 MHz	146.520 MHz FM
70 cm	420 to 450 MHz	446.000 MHz FM

Local repeaters extend range to 50 miles or more; listen first and find their offset and tone in a local repeater directory. ARES (Amateur Radio Emergency Service) and RACES run emergency nets; join one to learn how they work before you need them.

NOAA Weather Radio

Receive-only. Weather radios scan these seven channels automatically. Use one with SAME codes to get alerts only for your county.

Channel	MHz
WX1	162.550
WX2	162.400
WX3	162.475
WX4	162.425
WX5	162.450
WX6	162.500
WX7	162.525

Marine VHF

Channel	MHz	Use
16	156.800	Distress, safety and calling. Keep a watch on it.
9	156.450	Calling for recreational boats
22A	157.100	Coast Guard liaison after contact on 16

On a boat in distress, call "Mayday, Mayday, Mayday" on channel 16 with your vessel name, position, the problem, and the number of people aboard.

Sources

FCC: Citizens Band Radio Service (US government, public domain)
FCC: Family Radio Service and General Mobile Radio Service (US government, public domain)
FCC: Multi-Use Radio Service (US government, public domain)
FCC: Amateur radio service and 47 CFR Part 97, including 97.403 (US government, public domain)
FCC Enforcement Advisory 2018-03 on non-compliant handheld radios (DA 18-980) (US government, public domain)
NOAA Weather Radio (US government, public domain)
US Coast Guard Navigation Center: US VHF channel information (US government, public domain)
47 CFR Part 95, Personal Radio Services (US government, public domain)