Beginners guide to CB Antenna

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How to Install a CB Antenna

There is a wide variety of CB antennas available in the market and each has a different installation process to be followed. This guide is meant to highlight those steps that are common to all the CB antenna installations. It will also explain the factors that deeply impact the working of your CB antenna.

Choose a location

The first thing that you need to consider while installing your CB antenna is to select an appropriate location for it. Before you get your antenna home, make sure you have selected the point. This will help you buy the equipment required for the installation. Here are a few tips for getting this job done in the right manner:

  1. Try the center of your vehicle’s roof as the first mounting location for your CB antenna. This is the most ideal spot as it gives your antenna the maximum exposure and a wide ground plane to get anchored to.
  2. Try not to install your antenna on the bumper, license plate or the fender as these are the poorest locations for installation. Here you will receive half of the signal strength than the normal one.
  3. Fix your antenna in such a way that its coil is above the roofline of your car.
  4. Select a sufficiently tall antenna that should be mounted high enough on your vehicle.

Install your mount

This process can vary in its level of difficulty depending on the type of CB antenna you have. If you have a magnetic mount, then the process can be as simple as just sticking the mount to the selected location. On the other hand, the door jamb mount can require technical support for drilling the mount into the right point. You can get an idea about the type of your CB antenna and the installation process from the manual that will accompany the product.

Run the cable

Setting the proper route for the connecting cable is the next major step. There is a coaxial cable that will connect the CB antenna with your CB radio. Your job is to set it neatly and most inconspicuously. Below are the tips that you can follow for this:

  1. Buy a coaxial cable with removable PL259. This connector will help routing your cable easily through the smaller holes.
  2. Try to select that length of the cable that is completely utilized and nothing is left hanging down.
  3. Keep your line as noise-free as possible by avoiding the use of alternators.
  4. Try not to trim your coaxial cable down.

Tuning CB Antenna

Once you are successfully done with your CB antenna and CB radio installation, it is time to tune the system to the appropriate frequencies. This will make your CB experience more proficient and far-reaching and will ensure that you can make the maximum number of contacts from around the world through CB system in an unimpeded manner.

Why tune my antenna?

Tuning a CB antenna is the most crucial part in the process that determines the future performance of your CB system. A properly tuned antenna is necessary for enhancing the receiving and transmitting capabilities of your CB system, despite of the constant output power of 4 watts allowed for every CB radio in the market. If this tuning process is faulty, you can have a communication that is full of interference and broken signals.

How to tune the CB antenna

  1. First switch off your CB antenna and make sure your coax is out of the rear port.
  2. Now take your SWR meter and connect the antenna coax to the port named “antenna”.
  3. Now take the coax jumper cable and connect it to the point from where you took off the antenna coax from one end and to the transmitter position on the SWR meter from the other end.
  4. Clear the space around your vehicle and keep the windows and doors closed too.
  5. Now switch your CB radio on.
  6. Tune into channel 1.
  7. Adjust the SWR meter to the point indicating “FWD”.
  8. Depress the talk button for keying your mic and adjust the knob by turning it until you find your SWR meter at “set”. Now let your mic be unkeyed.
  9. Now bring the meter to the “reflect” status.
  10. Key your mic again and note the reading shown on the meter. If the reading is low, then everything is good to go. But if it is somewhere in the red zone, check your setup again while keeping the CB radio off.
  11. Now follow the same procedure for channel 40.

How to adjust your antenna by matching the channel 40 bandwidth

  1. If you get a reading on channel 1 that is higher than the one on channel 40, then that means your CB antenna is too short and its length needs to be increased. On the other hand, if the reading on channel 40 is higher than that obtained on channel 1, then shorten your antenna a little bit..
  2. If the readings on channel 1 and channel 40 are 1.2 and 2.3 respectively, then trim your CB antenna to a shorter length. For that purpose, you can adjust the length through the tuning tip or you can trim it straight by 1/4inch and put it back in place again. Be extra careful while trimming the CB antenna as a slightly larger trim can destroy your antenna performance.
  3. If the readings are 2.6 and 1.3 on channel 1 and 40 respectively, then increase your CB antenna’s length. You can simply adjust the length through the adjustable screws or you can use the spring between the mount and the whip.
  4. While adjusting, go ahead by small steps. During this procedure, make sure all the antenna components are there in their right places and keep checking them after every adjustment that you make.

Once you achieve a suitable SWR level for your CB system, you can either disconnect the SWR meter from the system or can keep it there for future testing.


By this location, we mean the area where you will be tuning your CB antenna. This place should be an open ground most preferably or it should not be crowded at least. Also keep your car carefully parked with all the doors and windows closed properly.


When a CB antenna is shorted to the ground, you will experience a very high SWR level for your CB system. You can expect this short to occur in the CB antenna stud or in the coax cable.



When the shield comes in contact with the conductor placed in the center of the cable, it shorts. This can happen due to many reasons, two of which are a natural crack in the cable since the time of purchase or a manufacturing defect. To be sure that your coax is working right, first disconnect it from the CB antenna and CB radio and then test it with a multi-meter. This meter will help you find out if there is any continuity to be seen between the center conductor and the shield. If there is no continuity between the two, your coax is perfectly fine. Otherwise you will need to get a new coax cable for your system.




If your CB antenna coupling nut and bolt are coming in contact with the antenna mount, then there is a strong possibility of your antenna stud to be shorted. If you put in the nylon washers carefully, you can prevent that from happening but that needs extra care. This kind of contact actually terminates the main purpose of the CB antenna stud i.e. to keep the antenna placed high above the ground with a distance between the two. Now you can use the multi-meter to check the health of your antenna stud connections. If you find the nut and bolt coming in contact with the mount, then readjust the nylon washer for taking care of this.


Poor electrical ground

This is different from the ground plane that we all know about. Firstly make sure your CB antenna mount is properly grounded to the chassis of your vehicle. If you are having a metal count, then you can ground it by bringing it in contact with the metal surface of the vehicle. For ease, take a multi-meter and test if your ground place is good or not. You can test this with a light or multi-meter just as you would test any vehicle ground. The easiest way to overcome this hurdle is to scrap some paint off your vehicle for exposing the metal underneath for better grounding. You can also use the grounding trap for grounding your CB antenna. If you have a magnetic mount, then there should be no issue for grounding as the magnet grounds through capacitive coupling quite easily.

Coiled coax

Coiled Coax

Generally when you have a very long coax cable, then it might be possible that there is plenty of it slacking behind even after all the installation has been completed and the cable routed. This extra coax is often twisted or coiled just like the CB antenna coil. If that happens, then your system will face signal feedback effect. To prevent this situation, select a longer route to pass your cable through to the CB radio.


Insufficient ground plane

We all know by now that a CB antenna requires a wide metal ground plane as a must for a perfect installation. Firstly select the ground plane with the widest metal coverage. If you are mounting the CB antenna anywhere on the sides, then keep the mount close to the vehicle’s main body. For vehicles without a metal chassis, use the No Ground Plane CB antennas.


Your CB antenna will perform poorly if it is being obstructed by the surroundings. This often happens when you mount your CB antenna somewhere very low on the vehicle like on its bumper. This reflects back the signals into the antenna and you get a high SWR level. To solve this problem, keep the CB antenna placed nicely above the roof-line and give it maximum exposure by placing it at the highest point.

Broken antenna

Usually the CB antennas have a fiberglass pole inside that has a copper wire wound around it. Any defect or crack in this wire can make your antenna useless and you obtain very high SWR levels. Check the continuity between the tip and base of your CB antenna with a multi-meter. You can use the multi-meter probe for this purpose in case the tunable tip is absent. In this case, if you don’t find any continuity between the antenna tip and base, then you need to replace your broken CB antenna.Also make sure that there is no capacitor connected to the system that might mislead the multi-meter.

Short or poor quality CB Coax

If you have tried all other solutions and your problem is still unsolved, try replacing your coax cable with a longer and better one. Select a cable from a good brand giving a high quality.

CB Antenna length

Most of the CB antenna manufacturers assure you of the antennas that are pre-tuned and you won’t need to tune them again.It might be true but not guaranteed to suit your case. Even if you trust these claims you will find out that these pre-tuned specifications will not work well with all the mounting situations. If after trying out everything else, you still want something big to solve your problem, then consider changing your CB antenna’s length as one of the last resorts. It might sometimes be necessary to trim down your antenna by 2’’ to reach the required SWR level but that is a very rare case. Always be careful while changing the length of your CB antenna through cutting as it can easily cut down more than required. The safest way to get this thing done is to trim a tiny portion of the CB antenna and measure the reading on the SWR meter. Do this side by side with each cut. This will ensure that you don’t exceed the level of required SWR.

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