All stations transmit at the same time but stations are limited to daytime operation only to reduce the radius of propagation.

Transmitter power is limited, station assignment codes are not shared by other NAVAREAS and stations alternate between daytime and nighttime operations.

Transmissions scheduled on a time-sharing basis, power is limited and station assignment codes are geographically separated .

Station codes are not shared by other NAVAREAS, transmissions scheduled on a time-sharing basis and power is limited.