From one to three channels are assigned in a particular area. Service is used on private aircraft. Channels are spaced 6 kHz apart. A specific block of 29 channels is assigned to each geographical area. Ground frequencies are 45 MHz lower and do not echo the airborne half of the conversation.
Service is used on passenger airlines.
Each TV channel is 6 MHz wide. The video carrier is 1.25 MHz above the start of the range. The audio carrier is 0.250 MHz below the end of the range. Citizen's Band Ch. In addition to the station's licensed channel, 462.675 may be used for emergency and traveler's aid by all stations.