Robots, Drones, and Radar: Electronics Go to War

Robots, Drones, and Radar: Electronics Go to War — page 5
The patterns traveled along the cable At the other end a receiver converted the patterns back into sound The telephone was used to send orders to soldiers in the trenches during World War I SCIENCE ooooO FILE FILE OOTTTTT 0 Real Sounds Radio telephony is the transmission of sound via radio signals rather than cables Radio telephony was invented in 1900 by Reginald Fessenden Earlier radios had sent electrical signals These signals included Morse code which used patterns of long and short signals Fessenden's invention meant that voices could be sent over radio It became the basis for most radio communication in the twentieth century RESCUE AT SEA By World War I messages could be sent without cables Italian inventor Guglielmo Marconi discovered how to send and receive electromagnetic radio waves through the air The radio was first used on ships It made headlines in 1912 when the RMS Titanic sent a distress signal The passenger ship was sinking in the Atlantic Ocean The radio signal alerted other ships which rescued 706 people 1 517 people died British engineers examine Marconi's radio equipment in 1897 They were interested to see if radio might have uses military