though not as sensitive as other forms of detectors it is well suited to the rough usage of portable outfits. Naval wireless Royal Navy In 1897, recently promoted Royal Navy Captain Henry Jackson became the first person to achieve ship-to-ship wireless communications and demonstrated continuous communication with another vessel up to three miles away. became the first British warship to have wireless telegraphy installed when she conducted the first trials of the new equipment for the Royal Navy. Starting in December 1899, HMS Hector and were outfitted with wireless equipment. On 25 January 1901, HMS Jaseur received signals from the Marconi transmitter on the Isle of Wight and from HMS Hector (25 January). US Navy In 1899 the United States Navy Board issued a report on the results of investigations of the Marconi system of wireless telegraphy. The report noted that the system was well adapted for use in squadron signalling, under conditions of rain, fog, darkness and motion of speed although dampness affected the performance. They also noted that when two stations were transmitting simultaneously both would be received and that the system had the potential to affect the compass. They reported ranges from for large ships with tall masts () to for smaller vessels. The board recommended that the system was given a trial by the United States Navy. Wireless telephony Fessenden In late 1886, Reginald Fessenden began working directly for Thomas Edison at the inventor's new laboratory in West Orange, New Jersey. Fessenden quickly made major advances, especially in receiver design, as he worked to develop audio reception of signals. The United States Weather Bureau began, early in 1900, a systematic course of experimentation in wireless telegraphy, employing him as a specialist. Fessenden evolved the heterodyne principle here where two signals combined to produce a third signal. In 1900, construction began on a large radio transmitting alternator. Fessenden, experimenting with a high-frequency spark transmitter, successfully transmitted speech on December 23, 1900, over a distance of about , the first audio radio transmission. Early in 1901 the Weather Bureau officially installed Fessenden at Wier's Point, Roanoke Island, North Carolina, and he made experimental transmissions across water to a station located about west of Cape Hatteras, the distance between the two stations being roughly . An alternator of 1 kW output at 10 kilohertz was built in 1902. The credit for the development of this machine is due to