Home Self-reliance Communications MURS and CB Radios

Communications Preparedness

MURS and CB. The other license-free radios.

Two services most households have never considered, each doing one job better than FRS or GMRS: MURS across a wooded property, and CB on the highway. What the rules allow, what the range really is, and how to set each one up.

MURS for the land CB for the road

Where FRS and GMRS fall short

Two problems the usual radios do not solve.

Most of this section points households toward FRS and GMRS, and for good reason: they are cheap, the radios are everywhere, and they talk to each other. Two situations sit outside what they do well.

The first is a large wooded property. FRS radios cannot use an external antenna, so the radio in the barn and the radio in the far pasture are both a few feet off the ground with trees in between. GMRS solves the antenna problem with a license and UHF gear, and it is the right answer for most rural households. But there is a license-free VHF service, the Multi-Use Radio Service, that allows a real outdoor antenna, uses a frequency that trees absorb a little less, and sits on five channels almost nobody else is using. For a farm or a wooded parcel, MURS is worth knowing about.

The second is the highway during an evacuation or a long drive through a storm. Every truck on the interstate still has a CB, and the drivers who see the jackknifed trailer or the flooded underpass ten miles ahead announce it on channel 19 before any app updates. No FRS or GMRS radio hears that. A $60 CB does.

Neither service replaces the family channel. MURS is a property tool and CB is a road tool, and this page treats each as exactly that.

Multi-Use Radio Service · FCC Part 95, Subpart J

MURS: VHF, no license, real antennas.

MURS was carved out of the old business band in 2000. The rules are short, and two of them are the reason the service exists for rural households.

The rules

  • No license. Operation is authorized by rule for anyone, the same as FRS and CB.1
  • Five VHF channels: 151.820, 151.880, 151.940, 154.570, and 154.600 MHz.2 The first three are narrowband channels; the last two allow the wider signal older business radios use.3
  • 2 watts transmitter output, maximum.4 That is less than a GMRS handheld, and it matters less than the next rule.
  • External antennas are allowed, up to 60 feet above ground or 20 feet above the top of the structure they are mounted on.5 This is the whole difference from FRS.
  • Voice, data, and telemetry are all permitted, which is why MURS driveway sensors and gate alarms exist.6
  • No repeaters, no store-and-forward, no phone interconnection, and no use from aircraft.7 MURS is simplex, radio to radio, by design.

Why it suits wooded land

Two things add up. First, the antenna rule: a MURS base antenna on the peak of a barn at 30 feet has a radio horizon of nearly eight miles, against a handheld's three and a half, and it sits above most of the trees instead of behind them.8 Second, the frequency: the loss a signal suffers per meter of foliage rises with frequency, so a 151 MHz signal generally comes through trees somewhat better than a 462 MHz GMRS signal.9 The effect is real and modest; it does not turn a valley into a plain, and antenna height still matters more.

The third advantage is quiet. On a Saturday, FRS channels in a subdivision carry every family's radios and half the county's. MURS channels carry a few businesses and almost no households. For a farm coordinating a hay crew, a household with a long driveway, or a homestead that wants one clear channel for its own people, that quiet is worth something.

Honest range

Handheld to handheld, MURS reaches about what FRS does: one to three miles on flat open ground, less in trees and hills. The difference appears when one end has a base antenna. A base at 30 to 40 feet with 2 watts and a good vertical antenna will reach handhelds across several hundred acres of mixed terrain and a few miles down the road. Two bases on two properties with tall antennas can reach five to ten miles. Ignore any package that promises more; range depends on height and terrain, and the antenna guide explains why.

Equipment

Radios must be FCC-certified for MURS; a ham radio programmed to 151.820 MHz is not legal to transmit with, however tempting.10 A handful of makers sell certified MURS handhelds and a few sell base or mobile units, typically $60 to $150 per handheld and $150 to $300 for a base. The selection is thinner than GMRS, and that is the trade. Because two of the channels are shared with older business systems, choose one of the three 151 MHz narrowband channels for household use and program the same one into every radio. Squelch codes (CTCSS or DCS) are allowed and useful for muting a business's chatter, with the same caveat as on FRS: a code hides other users from you, it does not hide you from them.11

Citizens Band Radio Service · FCC Part 95, Subpart D

CB: still the radio of the road.

CB peaked in the 1970s and never went away. It is a poor neighborhood radio and a good one for a household that drives long distances or may need to evacuate on an interstate.

The rules

  • No license, but the authorization is voided if you break the operating rules.12
  • 40 channels from 26.965 to 27.405 MHz.13 That is just below the 10-meter ham band and far below anything else on this site.
  • 4 watts carrier power on AM or FM; 12 watts peak on single sideband.14 FM was added to the CB rules in September 2021.15
  • Channel 9 is reserved for emergency communications and traveler assistance only. Every operator must give emergency traffic priority on every channel.16
  • Antennas up to 60 feet above ground or 20 feet above the building or tree they are on, whichever is higher.17
  • Plain language only, no music, no advertising, no political campaigning, no talking to other countries except Canada's General Radio Service.18

What it is actually for

Channel 19 is the highway channel by convention, not by rule, and on any interstate it is a live feed of what is ahead: the accident before the traffic stops, the closure before the sign, the ice on the bridge. During a regional evacuation, when cell networks are jammed and the radio stations are repeating the same bulletin, CB is the one source that is local to your stretch of road and updates in real time. The FCC's own list of permitted CB uses includes one-way transmissions warning travelers of hazardous road conditions, which is exactly what truckers do all day.19

It is also a fair choice for two vehicles traveling together, and for a farm with several tractors and pickups, where the long antennas are no burden. It is a bad choice for a neighborhood: the band is noisy, the antennas are eight feet long, and FRS or GMRS does the job better at a fraction of the fuss.

Honest range, and the 27 MHz problem

At 27 MHz a quarter-wave antenna is about 102 inches long. Every CB antenna shorter than that is a compromise, and the four-foot fiberglass whips on most pickups give up real performance for the sake of clearing a garage door. Vehicle to vehicle with typical antennas, expect two to five miles. A base with a full-size antenna at the height limit reaches ten to fifteen miles on a good day. Single sideband, at 12 watts and a narrower signal, roughly doubles the usable distance, but only to other radios that also have SSB.

The band has one habit no VHF or UHF service shares. Near the peak of the sun's eleven-year cycle, 27 MHz signals bounce off the upper atmosphere, and a 4-watt station in Ohio hears Texas and California. Old-timers call it "skip." It is entertaining, it is unreliable, and during those years it fills the channels with distant stations and noise that make local use harder. Do not plan around it in either direction.

Equipment

A basic 40-channel AM/FM mobile CB runs $50 to $100; adding SSB puts it at $130 to $250. Buy AM/FM at minimum, since FM is quieter between two FM radios and the truckers are still on AM. Handheld CBs exist and are almost useless: the antenna a handheld can carry is a tiny fraction of a wavelength at 27 MHz. Treat CB as a vehicle or base radio. The antenna is most of the purchase; a $40 radio on a good antenna beats a $200 radio on a bad one, every time.

Four services, one table

Where each one wins.

None of these four talk to the others except FRS and GMRS, which share channels. Pick one for the household, and add a second only for a job the first cannot do.

FRS GMRS MURS CB
BandUHF, 462 to 467 MHzUHF, 462 to 467 MHzVHF, 151 to 154 MHzHF, 27 MHz
LicenseNone$35, family, 10 yearsNoneNone
Power2 W (0.5 W on 8 to 14)5 W handheld, 50 W mobile and base2 W4 W AM/FM, 12 W SSB
External antennaNo, fixed to the radioYes, no height limit below Part 17Yes, 60 ft or 20 ft above structureYes, 60 ft or 20 ft above structure
RepeatersNoYesNoNo
Handheld range, real0.5 to 2 miles1 to 5 miles; 20+ via repeater1 to 3 milesHandhelds not useful
Talks toFRS and GMRSGMRS and FRSMURS onlyCB only
Best forKids, the yard, the trailThe household and the neighborhoodWooded acreage, farms, quiet private channelHighway travel and evacuation, vehicle convoys

One weekend

Setting up MURS on a property.

1. Pick the channel and program every radio the same way

Choose one of the three 151 MHz channels, set the same squelch code on every radio or none at all, and label each radio with the channel. A household that has to explain its channel plan during an outage has already lost ten minutes.

2. Put the base antenna as high as the rule and the building allow

A VHF base vertical cut for 151 to 154 MHz on a mast at the peak of the tallest building, within the 60-foot and 20-feet-above-the-structure limits. The antenna guide covers coax, grounding, and the power line clearance rule, none of which change because the service is license-free.

3. Run the base on 12 volts

MURS base radios draw little; a 2-watt transmitter is kind to batteries. A modest LiFePO4 battery from the power guide runs a MURS base for days.

4. Walk the property and map the coverage

With one person at the base, walk every corner of the land with a handheld and note where the signal drops. Mark the dead spots on a sketch that lives with the plan card. Knowing that the low field behind the pond is out of range is worth more than hoping it is not.

5. Add the data devices last

MURS driveway and gate sensors announce a vehicle on the same handhelds the household already carries. They are a genuine convenience for a long driveway. Set them to the channel you use least, so an alert does not interrupt a conversation.

One afternoon

Setting up CB in a vehicle.

1. Spend the money on the antenna

A magnet-mount or trunk-lip antenna of three to four feet is the practical minimum for a car; a pickup with a bed rail can carry a longer fiberglass whip. Mount it as high and as central as the vehicle allows. The install rules in the antenna guide apply in full: power from the battery, fused, radio and cables clear of the air bag zones.

2. Tune the SWR, and this time it is not optional

CB antennas are short relative to the wavelength and are sensitive to their mounting; most have an adjustable tip for exactly this reason. Check SWR on channels 1, 20, and 40, adjust the tip until the readings are low and balanced, and recheck if you move the antenna. An untuned CB antenna is the most common reason a new CB "does not work."

3. Program the habit, not the radio

Channel 19 on the interstate, listening, with the squelch set so the road noise does not open it. Channel 9 if you need help or see someone who does. Whatever channel your traveling companions agree on for your own group. That is the entire operating plan for a household CB.

4. Know what you are hearing

Channel 19 is unfiltered. Some of it is useful, some is profane despite the rule against it, and some is wrong. Apply the two-source habit from the information hygiene guide to anything that would change your route: a second trucker confirming it, a sign, a visible line of stopped brake lights. Then act.

Seen in the forums

Common mistakes.

Programming a ham radio to MURS frequencies

Listening is fine. Transmitting on a Personal Radio Service with a radio that is not certified for it voids your authority to operate and is a violation. Buy a certified MURS radio or use GMRS with a license.

Expecting MURS handhelds to outrange FRS

Hand to hand they are about even. The advantage is the base antenna and the quiet channels. Without a base, you have bought a more expensive FRS radio that talks to fewer people.

A handheld CB

A rubber antenna a foot long on a 27 MHz radio is a toy. If CB is the goal, it lives in a vehicle or at a base with a proper antenna.

Chasing skip

Hearing Texas from Ohio on 4 watts is fun and it means nothing for your plan. Plan for the two to five miles you can count on, and enjoy the rest as weather.

Illegal amplifiers

CB amplifiers are sold openly and put a station far past the 4-watt limit, which voids the authorization to operate. They splatter across neighboring channels and into nearby televisions and radios. The legal fix for weak range is a better antenna.

Using CB as the neighborhood radio

It can be done and it is worse in every way than FRS or GMRS: bigger antennas, more noise, no handhelds worth carrying. CB is for the road.

Where to go from here

Choose the service, then build it.

GMRS Radio Guide

For most households, including most rural ones, GMRS with a $35 license is still the right first choice. Here is why, and how.

Read the guide →

Antennas and Radio Installs

The MURS base on the barn and the CB in the truck both live or die by the antenna, the coax, and the install.

Read the guide →

Transportation

Evacuation routes, fuel, and the vehicle kit a CB belongs in. The Transportation section covers the rest of the road.

Read the guide →

Sources

Where this information comes from.

All sources accessed September 5, 2026. Every rule is quoted from the current electronic Code of Federal Regulations, Title 47, Part 95, unless noted.

  1. 47 CFR 95.305, Authorization to operate Personal Radio Services stations without individual licenses. ecfr.gov
  2. 47 CFR 95.2763, MURS channels: 151.820, 151.880, 151.940, 154.570, and 154.600 MHz. Same document as source 1.
  3. 47 CFR 95.2773, MURS authorized bandwidths: 11.25 kHz on the three 151 MHz channels, 20.0 kHz on the two 154 MHz channels. Same document.
  4. 47 CFR 95.2767, MURS transmitting power limit: 2 watts. Same document.
  5. 47 CFR 95.2741, MURS antenna height limit: 60 feet above ground or 20 feet above the highest point of the structure. Same document.
  6. 47 CFR 95.2731, Permissible MURS uses: voice, data, image, telecommand, and telemetry. Same document.
  7. 47 CFR 95.2733 (no repeaters or store-and-forward), 95.2749 (no public switched network interconnection), and 95.2707 (no airborne use). Same document.
  8. Repeater Builder. "A Quick Overview of the Radio Horizon." Horizon in miles equals about 1.415 times the square root of antenna height in feet. repeater-builder.com
  9. ITU-R Recommendation P.833-10, Attenuation in vegetation. Specific attenuation through foliage rises with frequency across the VHF and UHF range. itu.int (PDF)
  10. 47 CFR 95.335, Operation of non-certified transmitters prohibited; use of a non-certified transmitter voids the user's authority to operate. Same document as source 1.
  11. 47 CFR 95.377, Tones and signals: selective calling and tone-operated squelch are permitted as ancillary to voice. Same document.
  12. 47 CFR 95.905, Authority to operate CBRS stations voided by violation of operating rules. Same document.
  13. 47 CFR 95.963, CBRS channel frequencies: 40 channels, 26.965 to 27.405 MHz. Same document.
  14. 47 CFR 95.967, CBRS transmitter power limits: 4 watts mean carrier power for AM or FM voice, 12 watts peak envelope power for SSB. Same document.
  15. 47 CFR 95.971, CBRS emission types, as amended at 86 FR 53565 (September 28, 2021): FM voice emission type F3E added to AM and SSB. Same document.
  16. 47 CFR 95.931(a), Permissible CBRS uses: any channel for emergency communications; priority to emergency communications at all times; channel 9 reserved for emergency communications and traveler assistance only. Same document.
  17. 47 CFR 95.941, CBRS antenna height limits. law.cornell.edu
  18. 47 CFR 95.933, Prohibited CBRS uses, and 95.333, Prohibited uses (all Personal Radio Services). Same document as source 1.
  19. 47 CFR 95.931(b)(2), one-way transmissions to warn travelers of hazardous road conditions. Same document.