Single Side Band Explained

All CB radios operate on AM, which is the same type of transmission as a typical AM radio station.  In addition, some higher-end CB radios are equipped with single sideband (SSB), which is a different mode of transmission. This transmission provides a refinement of amplitude modulations which uses transmission power and bandwidth more effective and efficiently. Using only one of the sidebands, as opposed to an AM signal which consists of two redundant sideband signals of SSB are suppressed. (The sideband channels are technically the upper and lower halves of the 40 regular AM channels that are already available).

When you mix together two signals with different frequencies, you produce two new signals — one with a frequency that's the sum of the first two frequencies, the other with a frequency that's the difference between the first two frequencies. For example, mix an audio tone that has a frequency of 1 kHz (one kilohertz, or one thousand cycles per second) with a radio carrier signal of 1000 kHz, and you get two new signals, at 999 kHz and at 1001 kHz. The 999 kHz signal is in the lower sideband (LSB), and the 1001 kHz signal is in the upper sideband (USB). The carrier signal — a steady, continuous signal of unvarying frequency — sits between the two sidebands, not really carrying anything at all. It provides a zero-reference for the sidebands; in the example above, each of the sideband signals is 1 kHz away from the carrier signal.

You will have access to the Upper & Lower Sideband Modes (USB, LSB), on each of the 40 channels, in addition to the "Regular" (AM) mode, using the "Am/USB/LSB switch. When switched over to a sideband, each receive signal must be "fine-tuned" in with the clarifier or voice lock control found on the SSB CB radio, otherwise people will sound garbled. Keep in mind that when switched to a sideband, you can only communicate with other CBers that have that same SSB capability as well. In order to avoid interference to those using AM (SSB stations are authorized to use 12 watts, as opposed to 4 watts for AM stations) and to more easily locate other SSB stations. This allowed higher wattage provides a higher power which in turn increased the range and clarity than a regular CB while in AM mode

The advantages of single sideband:

  • More channels
  • Higher power (12 watts is allowed on SSB, only 4 watts is allowed on AM)
  • Quieter reception

Q codes are used in many kinds of radio communications, including CB sideband but not typically on CB AM

OSL Terms

  • QSL Card - Personalized postcard sent to confirm a conversation.
  • QSL - Term used on SSB for "Roger"; i.e.- "QSL on that". While the Q signals were originally used on CW in the Amateur Radio Service, and often are the butt of complaints, they have found their way into CB’s society, and live with them we must.
  • QSK - Another Ham term, reformatted for CB. Means – "Break" QRM - Noise or interference
  • QSY - Change or changing channels/frequency.
  • QRT - Off the air; Signing OFF.
  • QRX - To wait, or standby.
  • QSB - Noise
  • QSO - Pronounced "Que-Sew", meaning "conversation" or "communication".
  • QSY - Move to a different channel or frequency.
  • QTH - Location