The Truth on CB Power

One of our most asked questions is, "Who makes the biggest, baddest CB Radio?" The truth is that all CB radios are created equal. In order for them to be allowed into the country, they must meet a certain standard. That is, the power must not exceed 3.8 watts.


There are two ways to figure the power of a radio. One is "RMS" and the other is "PEP." When you walk into a CB shop and ask how much power a radio puts out, they will answer you with the PEP numbers. The simple way to know the difference between the two ways of measuring power is that RMS is the average power the radio puts out. This is the way the FCC would measure the performance of a radio. Yes, Uncle Charlie is still around.


A load of radios will arrive in customs and a federal inspector will open the container and choose one radio at random to test. If the power of the radio does not exceed federal limits, the whole load will be allowed into the country. If it fails to pass, the whole load is denied entry. Therefore, the CB importers like Cobra make certain that their radios will pass inspection. Now you know why shops recommend that you peak and tune a radio.


Now comes PEP. Peak Envelope Performance is the absolute top end performance of a radio. This is usually established by whistling into the microphone and noting the maximum power reading on the meter. This is done to impress the customer. Most drivers like to see this number as high as possible. Most drivers don't understand that in the real world these numbers are misleading. Drivers are conditioned to look for these high numbers, not realizing that these numbers can only be attained on the bench. If you don't show them these numbers they will drive down the road to a shop that will promise them the sun, the moon and the stars. They will buy the same radio and pay more for it--just because the shop tells them it does five watts more than you told them. So, most shops use PEP meters. The numbers impress the customer and sales are the name of the game.


How can you judge the performance of a radio? Look at the meters being used. Look at the top end reading when talking at a normal tone of voice. This will tell you the power you can expect to attain in normal operation. This number should be about two thirds of the PEP number they will quote you. Just as a matter of information, most radios are built with a five-watt final. So, if some shop tells you that they can get 40 or 50 watts out of one, draw your own conclusion. There is no way of making this happen. There is nothing that is learned in the military that no one else knows. In short, no one but Jesus Christ can change the laws of physics.


As with all other purchases, use common sense. All true CB Radios start life equal; some are able to generate more audio than others are. Some are able to generate larger carriers than others. Which CB radio is the best? They are all basically the same. Choose the one that you like the best. You won't go wrong.

Written By: Stan Wells