ELECTRONICS AT WAR In July 1940 the Germans planned to knock Great Britain out of World War II 1939 1945 They wanted to invade Britain and planned surprise air raids that would destroy the British Royal Air Force RAF On July 10 German fighters and bombers flew toward Britain but RAF fighters were waiting Unknown to the Germans the British had developed a warning system called radar It used radio waves to search for enemy airplanes The waves bounced off objects so operators could see German airplanes 200 miles 320 kilometers away Pilots from the British RAF race to their airplanes after receiving news of an approaching German attack air
In 1906 the US engineer Lee de Forest invented a valve that could make electrical current stronger The valve became the basis of later devices that used electrical current That gave RAF pilots time to get into the air to meet the raiders Radar helped the RAF fight off German attacks until October 31 1940 Then the Germans abandoned their planned invasion Britain would fight on in World War II CHANGING CURRENT The use of radar showed the power of electronics in warfare Electronics is the use of devices that change electrical current In the twentieth century electronics became the basis of inventions such as radio and television radar and computers In modern Warfare electronics are used to make vehicles and weapons automatic Modern Warfare sometimes resembles video games Unmanned aerial vehicles or drones attack the enemy In the future wars will increasingly be fought using weapons electronic
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
