The mother of all antenna couplers: Harris RF-601A.

The mother of all antenna couplers the Harris RF-601A. Ruggedly designed to meet any weather conditions head-on, this 1 kW manual/automatic hf antenna coupler is solidly constructed out of die-cast aluminum. Its internal is cavity pressurized with inert nitrogen gas. Frequency coverage is from 2 to 30MHz and electrically couples the transmitter with practically any antenna. A perfect match with the rugged Comrod marine fiberglass constructed marine antenna.