ELECTRONIC COMMUNICATION Communication is crucial for delivering orders during military operations Before the invention of electronics messages were sent in person or by signaling with drums flags or smoke Fhe first electrical telegraph was invented Il in the 1820s The telegraph sent messages along a cable to a receiver using electrical signals The signals were pulses of different voltages The British were the first to use the telegraph in battle during the Crimean War against Russia 1853 1856 Union soldiers unspool a cable to carry telegraph signals during the US Civil War 1861
ooooo SCIENCE FILE British engineers in Crimea ran telegraph cables from the front line to their headquarters over 30 miles 48 km away The British commander there Lord Raglan used the telegraph to communicate with his generals Field Phones During the 1870s scientists made the first attempts to send speech by telegraph As a result they invented the telephone This was a milestone in human communication The user spoke into a mouthpiece Then the telephone changed the voice vibrations into patterns of electrical resistance Field telephones used cables to communicate between command posts and the front line Long cables were unrolled from spools as soldiers advanced The British Army first used field telephones during the Second Boer War 1899 1902 when the British were fighting Afrikaner farmers in South Africa An officer uses a field telephone in World War I 1914 1918 The handset was carried in a box connected to a long cable telephone
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
In 1906 Lee de Forest invented the Audion valve In 1914 the valve was used to make wireless radios that could transmit and receive speech The transmission of speech was called wireless radio telephony A US soldier checks his radio signal during a 2010 operation in Afghanistan The antenna next to him picks up radio signals from satellites WORLD WAR II In World War II the US military developed the first walkie talkies These were portable two way radios mounted on a backpack For communicating over long distances the Americans created relay networks These networks were based on radio stations that were a relatively short distance apart A radio signal traveled from station to station The networks linked the government in Washington DC with commanders in Europe and Pacific the
