The VLF transmitter DHO38 is a transmitter for VLF of the German Navy near Saterland, West-Rhauderfehn, North-Germany. It is used to transmit coded orders to diving submarines of the German Navy and of Navies of other NATO-countries. DHO38 transmits since 1982 on 23.4 kHz with a power up to 800 kilowatts. DHO38 uses an umbrella aerial, which is carried from 8 steel tube masts with a height of 352.8 metres. Each pylon stands on a huge ceramic ball, which serves as an insulator for a voltage of 300 kilovolts.