VLF Transmitter Cutler

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 relatively low data rate.

The transmission consists of a continuously encrypted minimum-shift keying (MSK) signal capable of multi channel operations.

Each array consists of a ring of 13 tall metal masts connected at the top by a network of horizontal cables.

The cables form six diamond-shaped (rhombic) "panels" radiating from the central tower at angles of 60°, so from above the antenna has a snowflake shape.

Under the antenna is a huge earthing system consisting of a radial network of cables buried in the ground, that serves as the bottom plate of the "capacitor".

Therefore, the antennas have a deicing system which runs large 60 Hz electric currents through the wires, heating them, to melt the ice.

The present station operating procedure, based on a past RADHAZ survey, does not allow work on the bow-tie area towers or panels while transmitting either array.

The objective of the four-panel tests was to allow painting and normal maintenance on the bow-tie area towers of the array which is entirely inactive.