Tuning a CB radio is fairly difficult. The antenna has to be adjusted just right or else the SWR will be unbalanced, which can actually mess up the radio. This how-to is just to teach you how to tune the antenna using an SWR meter.
First of all, make sure that all the doors and the trunk are closed. Then, park your car at least 10 yards away from any big buildings, other cars, or trees. Also, make sure no one is standing close to the car. Any of these can mess up the reading. Now, you have to attach the meter in between the antenna and the CB. Using shorter coax cables, attach the antenna to the ANT end of the SWR meter, and the CB to the other end. Now that it is attached, check for the switch on the meter that can be set to FWD or REF. Set it to FWD. Now turn the CB to channel 1, and key the microphone. Adjust the knob labeled SET until the needle reaches full. Now that this is done, turn the switch to REF. Key the microphone again. Record this number, and then switch the CB to channel 40. Key the microphone again, and then record this setting. Very important: The microphone must be the same distance from the meter each time you key it. The objective here is to get the two numbers to a perfect 1:1 ratio. However, as long as the ratio is under around 1.4:1, you will be ok. My CB, after tuning, is now around a 1.1 or 1.2:1. This simply means that the numbers either match or are very close to matching. Now we go on to tuning.
If your SWR reading was higher on channel 40 than it was on channel 1, then it simply means the antenna is too long. If it was higher on channel 1 than it was on channel 40, it is too short. This is really easy to change if you own a tunable-tip antenna. If you own an antenna like this, you can simply unlock the tip and raise or lower the antenna. Continue tuning until you reach a good ratio. If you own a fiberglass whip antenna, it is a little more difficult. First, you have to remove the tip and cut until you can access the wire coil. If it needs to be shortened, you have to begin cutting in around ¼” increments until it is correct. Now, if it is too long, you have to take the top coil and continue moving it out in slight increments until it is correct.
Tuning a CB can take a lot of time, and it is fairly difficult. However, once it is done, they are a lot of fun. If tuned correctly, you will get the most life out of your radio and the most distance and clarity out of your antenna.
