Exploring Different CB Modes: AM, FM, and SSB

Exploring Different CB Modes: AM, FM, and SSB


In this blog, we will delve into the world of CB radio and explore the different modes of transmission: AM, FM, and SSB (Single Sideband). These modes have their unique characteristics and are used for various purposes in radio communication. Let's take a closer look at each mode and compare their performance.

AM: Amplitude Modulation

The first mode we will discuss is AM, or Amplitude Modulation. AM is widely used in broadcast radio and provides good audio quality. However, in the world of CB, AM is not normally the preferred mode of communication. The main issue is sound quality, whilst AM can provide clear communication under optimal conditions it is more susceptible to noise and interference, so FM and SSB are better options.

One of the advantages of AM is that it is compatible with older radio equipment.

FM: Frequency Modulation

Next, let's move on to FM, or Frequency Modulation. FM is commonly used in commercial radio broadcasting and offers superior sound quality compared to AM.

In terms of signal strength, FM will normally outperform AM. However, it is important to note that FM does not always have the same advantage in all scenarios.

FM has the advantage of being less susceptible to noise and interference compared to AM, making it the dominant mode for communication.

SSB – Single Sideband

Lastly, we have single sideband mode, which is a popular choice among CB radio operators, especially for long-distance communication.

Single Sideband is a form of Amplitude Modulation (AM) where one of the sidebands and the carrier wave are removed, leaving only one sideband (either the upper or lower sideband) to carry the information. This makes SSB more efficient in terms of power usage and bandwidth compared to traditional AM.

SSB offers superiority in terms of signal quality.


When comparing AM, FM, and SSB modes, SSB will always offer the best results in terms of signal quality, especially in challenging conditions. FM provides superior sound quality, but its advantage diminishes when the signal strength drops below a certain level.

While AM has its place in broadcast radio, it is not commonly used in due to its limited performance. SSB, on the other hand, provides a reliable means of communication, particularly in long-distance scenarios.

Whether you are a seasoned CB operator or just starting your journey in the world of CB communication, understanding the different modes and their characteristics is essential. By choosing the right mode for each situation, you can ensure clear and efficient communication.