How to Calibrate a CB Radio Antennaby Allen Coleman
Calibrating the antenna to your Citizen Band radio is needed to get the maximum performance out of your CB. To calibrate your antenna you will need to use an Standing Wave Radio to get a read on your "Reflected Power" and know how to adjust your antenna. Higher frequencies will need a longer antenna and lower frequencies need a shorter antenna. To properly calibrate your antenna you will need to find the balance for your lower frequencies and the higher ones.
Connect the SWR meter to the antenna and the CB radio by twisting the end of the antenna's cable onto the input on the SWR meter. Twist the cable coming from the SWR meter onto the antenna input on the back of the CB.
Set the CB radio to channel 1 and switch the SWR meter to calibrate. Press the microphone button but do not talk into it. Switch the selection on the SWR meter to "SWR" while holding the mic button. If the reading on the meter is 1:5 or less you don't need to adjust the antenna. If it is 2 or above you will need to adjust the antenna.
Turn the CB to channel 40 and run the test again with the SWR meter as explained in step 2. If your SWR reading is higher on channel 1 then channel 40 you need to lengthen your antenna. If the reading on channel 40 is higher then channel 1 you need to shorten your antenna.
Shorten or lengthen your antenna. If your antenna has a tunable tip you can do this by simply adjusting the tip up or down. If you have an antenna without a tunable tip you can use a pair of wire cutters and cut an inch off the tip of the antenna. If you need to lengthen the antenna you will need to purchase a longer antenna.
Test the antenna with the SWR meter after you make the adjustments to the antenna see if further adjustments are required.