By: Jeremy Neisser
CB radio is a very popular means of communication on the road. Carrying over miles, it seems as though they can go forever.
But is this really true?
To know how far a CB radio will work we must first understand what factors affect their range and how steep these factors are.
How Far Do CB Radios Work
The average range of a CB radio is 3 miles. There are several factors that influence the range including radio power, power source, antenna length & type, antenna quality, height and direction, mount location, installation quality, weather, and terrain.
FACTORS THAT INFLUENCE RANGE
Antenna Length & Type:
Taller antennas give the radio more line-of-sight distance, but having an antenna longer than 6 feet could get it into trouble. The FCC regulates that all antennas are to be mounted at least 6 feet from any person! This means if your car has a roof rack, you can't have a long antenna sticking out of it.
This means that your antenna can only be 6 feet long.
Antenna Height & Direction:
The higher you are, the more line-of-sight distance you'll get; but if it's pointed in the wrong direction (down at your car), you won't pick up any signal whatsoever. A low antenna pointed at the horizon can pick up a very weak signal better than one pointed up at the sky.
Where you mount the antenna has more to do with safety than range. Regulations vary, but usually require that it be mounted at least 3 feet from any window.
Sometimes it's on the rear of the car or truck, sometimes on the roof.
You can't expect great performance if the antenna is loose or wobbly. There are ways to make it sturdy, but you probably don't want to do them yourself unless you're a pro.
Bent coax cable can also impair range, especially if the core wire is exposed at the bend.
If you want to get things right, it's best to go with a teardrop-shaped antenna with a built-in spring and mount it firmly on your roof.
Radio Power & Output/SSB:
The better your radio can transmit, the more power it has. This is what helps close the gap between people who have cheap radios and those with powerful ones . At least match each other's output wattage.
If one guy has a 40w radio and another guy has a 5w radio - guess how far their signals will travel?
If you're in a valley between two hills, the side of the hill toward your buddy might be blocking his signal. If he's in a valley and so are you - what will happen to your signals? They'll bounce right off the ground and interfere with each other!
A CB radio is affected by weather conditions for obvious reasons, so if it's raining, foggy or misty you might have a tough time seeing very far with the naked eye.
When it gets cool at night, radio waves tend to scatter better which actually lowers the effective range since most people don't want to transmit at such low temperatures!
Keep in mind that humidity can be just as bad for radios as rain or snow - the air has more water molecules in it which prevents radio waves from traveling through as easily.
There are major differences in the way antennas look, yet they do the same thing. A $20 antenna may not be as durable as a $50 one, but if it's built right you'll pick up more signal than someone with a $500 antenna!
This is kinda obvious - unplug your radio and you won't transmit or receive anything! Batteries usually last about 4 hours but that really depends on how much power you're using and what kind of batteries you put in there.
What does all this mean?
It means that: If everyone has matching radios, then power output will decide who can talk the longest distance.
You'll get a longer range while traveling on flat ground compared to hilly terrain. Taller antennas will give you a better range.
You'll get a better range in dry conditions compared to humid or wet ones. You can still communicate if your car isn't moving, but the further away you're trying to talk to someone - the lower the success rate!
How far do CB radios work? About 3 miles under perfect conditions.
IF everyone involved has matching equipment that's properly installed and mounted. If you don't have at least 10 watts of power coming out of your radio, it'll be difficult getting any signal whatsoever beyond a few hundred yards.
Range estimations will vary depending on which model of CB you have. The range is always given for a "typical" transmission in terms of antenna height, power output/mode, etc.
You can't compare the ranges between radios that use different modulation modes (AM vs SSB), but it gives you an idea on how far each radio would usually transmit on average.
Here are some ways to improve your range:
Shorter Car Antenna:
CB antenna kits wouldn't hurt. Having an antenna taller than 6 feet makes it illegal in many areas, so if you can find a way to lower it down...
Better Radio or Better CB Radio:
Upgrading from a stock radio to one with more watts is always a good idea. You'll get better range and be able to talk over top of other people who are hampering your signal.
If you're set on getting the best range possible, then a CB radio with digital signal processing (DSP) is your best bet. DSP reduces noise and makes it easier to communicate at greater distances.
Better CB Antenna:
A better antenna will pick up more signal and transmit further! There's no question that getting a high-quality metal whip antenna instead of the factory rubber one would help. They're not expensive either - usually less than $50 for a whole kit!
Check out this review of the Best CB Radios - I'm pretty sure there's at least one model that has DSP!
Ask for Help: Don't know what to do or which direction you should point your antenna?
Ask for help! If you're in an area where CB radio is popular, you'll be surprised at how much help can come from even the most unexpected places.
There are tons of ways to get better range with your CB radio - it's all about maximizing signal.
Whether you change your car antenna, put up a high-gain one or keep good communication with others...if you stick to these things then there aren't any limits as to how far you'll be able to communicate over the airwaves!
What is skip?
A CB radio is capable of receiving the messages (both audio and data) made by other CBs which are within range. However, messages can be transmitted over very long distances at night through "skip" or "skywave".
This is when signals bounce off the ionosphere (the layer of several charged particles above the earth's surface) back to earth again further away from their original source.
Sometimes messages can skip hundreds or even thousands of miles.
During normal conditions, these messages only travel vertically to a maximum height of about 3000 feet; however, during certain propagation conditions, they may reflect back down to ground level again up to 1500 miles away!
Messages traveling in this way are referred to as "ground waves", and messages which do not follow this are called "sky waves". Sometimes skip can still occur during the day.
When skip occurs, the distance between CB radio increases. This does not happen often enough to be useful on a regular basis for ham radio operators, but it is fun when it happens!
If you are interested in participating in the activity of using CB radios to communicate over long distances at night by skywave propagation, there are some things that you might need to know.
What is the Average Handheld CB radio range?
On average, a handheld CB radio can transmit a clear signal up to 200 yards in an open field with a stock rubber ducky antenna, in a vehicle, the estimate is one mile of clear transmission.
Handheld CB Radios are 4 watts so they have a limited range based on their power. Even with a magnet mount antenna, your range will be limited as the power from the handheld CB radio is only so strong.
The range of a CB radio depends on several factors including a cb antenna, power output, frequency and propagation.
-You May Like: The Best Handheld CB Radios
Though limited by regulations to 10 watts maximum power output, there are few things you can do to increase your range including using an external cb antenna or getting a higher wattage radio.
Remember though that FCC regulations state radios aren't allowed to have antennas over 6 feet in length.
If everyone has matching antennas then antenna design will decide who can talk the longest distance. You'll get better range when aiming at flat ground compared with hilly terrain
Long-range communications are more dependent on propagation conditions than the type of antenna used. However, using a high gain (aka directional) antenna can be very useful in these types of situations.
The shortest range is when you're in the dead center and side to side with the other party's antennas at 90 degrees.
You'll get better range if they are closer or further away from 90 degrees in either direction than you!
If both parties have matching radios and antennas and good communication, then frequency will decide who can talk the longest distance.
Higher frequencies generally travel shorter distances than lower frequencies however they also attenuate less quickly which means they might still go just as far despite obstructions or interference that would otherwise block them out altogether.
It's not uncommon for communications to be possible at distances of well over 100 miles (160 km) depending on the frequencies used and atmospheric conditions that exist between the two points.
How does a base station antenna help with range?
Base station antennas will help you communicate over a greater distance (groundwave and/or skywave) but it won't help if everyone has poor antennas or low power radios.
To get the most range, upgrade your CB radio to one that has DSP and buy an expensive antenna with good gain such as a firestik antenna.
If you live in a well-populated area, then your range won't be good unless you have a pretty high-power radio and a really good antenna that can pick up groundwaves at night.
You Might Like: Antenna Gain vs Distance - Explained
In Conclusion: How Far do CB Radios Work?
CB radios can transmit over a vast range of distances, depending on the power output of the CB radio and surrounding conditions. In clear conditions, you can talk from up to 30 miles away without talking through a repeater. With a tower, you could potentially get up to several hundred miles of coverage!
If everyone has matching radios, then power output will decide who can talk the longest distance. You'll get a longer range while traveling on flat ground compared to hilly terrain
Hi & Welcome!
My name is Jeremy and I have been an avid car nut for many year. My first car was an 1987 Honda CRX. I put in my first Kenwood stereo, amp, 2 10" JLs and a CB Radio in it and have been an avid user of CBs and car radios for years. I'll do my best to share my tips, information and thoughts to help you with whatever question you might have, ABOUT ME