In September of 1958 the Class D CB service was created on the 11-meter band at 27 Megacycles, and this band became what is popularly known today as CB (Citizen Band) Radio. Originally there were 23 CB channels until the 40-channel band plan was implemented in 1977. Channel 9 was designated for emergency use and channel 19 became widely adopted for truck drivers and highway traffic communication.
1) 26.965 MHz 9) 27.065 MHz 17) 27.165 MHz 25) 27.245 MHz 33) 27.335 MHz 2) 26.975 MHz 10) 27.075 MHz 18) 27.175 MHz 26) 27.265 MHz 34) 27.345 MHz 3) 26.985 MHz 11) 27.085 MHz 19) 27.185 MHz 27) 27.275 MHz 35) 27.355 MHz 4) 27.005 MHz 12) 27.105 MHz 20) 27.205 MHz 28) 27.285 MHz 36) 27.365 MHz 5) 27.015 MHz 13) 27.115 MHz 21) 27.215 MHz 29) 27.295 MHz 37) 27.375 MHz 6) 27.025 MHz 14) 27.125 MHz 22) 27.225 MHz 30) 27.305 MHz 38) 27.385 MHz 7) 27.035 MHz 15) 27.135 MHz 23) 27.255 MHz 31) 27.315 MHz 39) 27.395 MHz 8) 27.055 MHz 16) 27.155 MHz 24) 27.235 MHz 32) 27.325 MHz 40) 27.405 MHz