Unit 7
Unit 7
Alexander graham Bell an inspired black-haired scotsman of twenty eight, on the eve of marriage, vibrant and alive to new ideas." Alexander Graham bell The Man who invented the Telephone Alexander Graham Bell 1847to1922
Alexander Graham Bell " . . . an inspired black-haired Scotsman of twenty eight, on the eve of marriage, vibrant and alive to new ideas." Alexander Graham Bell : The Man Who Invented the Telephone
Telephone Facts e The inventor of the telephone in 1892, opens long-distance service between New york and chicago over 800 miles of open wire line. Only 14 years before, in 1878, he had predicted that some day a man in one part of the country may communicate by word of mouth with another in a distant place
Telephone Facts The inventor of the telephone in 1892, opens long-distance service between New York and Chicago over 800 miles of open wire line. Only 14 years before, in 1878, he had predicted that some day "a man in one part of the country may communicate by word of mouth with another in a distant place
Th he first Telephone call Mr Watson come here i want yo Telephone comes from the Greek word tele meaning from afar, and phone meaning voice or voiced sound
The First Telephone call "Mr. Watson, come here, I want you!“ Telephone comes from the Greek word tele, meaning from afar, and phone, meaning voice or voiced sound
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The complete telephone man e He was mobile, mechanized and well equipped. With his tools around his waist he carried telephones on his back chest and in his bicycle sack. As today telephone men 80 years ago were safety -minded which in that era included wearing your sleeve guards and trouser clips
The complete telephone man He was mobile, mechanized and well equipped. With his tools around his waist, he carried telephones on his back, chest and in his bicycle sack. As today, telephone men 80 years ago were safety-minded, which in that era included wearing your sleeve guards and trouser clips
ne telepnone is an electrical instrument Speaking to the transmitter makes its diaphragm(震动膜) vibrate. this varies the electric current, causing the receiver's diaphragm to vibrate. This duplicates the original sound
The telephone is an electrical instrument Speaking to the transmitter makes its diaphragm（震动膜） vibrate. This varies the electric current, causing the receiver’s diaphragm to vibrate. This duplicates the original sound
TELEPHONE LINE RECEIVER TRANSMITTER CARBON GRAINS CARBON, E GRAINS r雄越 TD TRANSMITTER RD RECEIVER BATTERY