Transmitter
Cutler Naval Station has a transmission power of 1800 kW, and it was at one time, and perhaps still is, the most powerful radio transmitter in the world. As with all VLF stations, the transmitter has a very small bandwidth, and so cannot transmit audio (speech) but only coded text messages, at a very slow data rate. The transmission consists of a continuous encrypted FSK (F1B) signal at 200 baud. The transmitter operates on 24.0 kHz. In the past it operated on 17.8 kHz. The callsign of the station is NAA.
Read more about this topic: VLF Transmitter Cutler