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Lesson 1 Common Alloys 1

Lesson 2 Steel and Other Alloys(1) 5

Lesson 3 Steel and Other Alloys(2) 11

Lesson 4 An Electric Current 17

Lesson 5 Electric Batteries 23

Lesson 6 Magnetism and Electromagnetism 27

Lesson 7 Electric Motor 33

Lesson 8 Electric Motors and Generators 37

Lesson 9 Valves 42

Lesson 10 Thermionic Valve 48

Lesson 11 Tubes and Transistors 53

Lesson 12 Marconi and the Invention of Radio(1) 60

Lesson 13 Marconi and the Invention of Radio(2) 66

Lesson 14 Radio 73

Lesson 15 Television 80

Lesson 16 Television Reception 86

Lesson 17 Lasers 91

Lesson 18 Applications of Lasers 98

Lesson 19 Computers(1) 103

Lesson 20 Computers(2) 109

Lesson 21 Atoms and Elements 115

Lesson 22 Atomic Energy(1) 122

Lesson 23 Atomic Energy(2) 128

Lesson 24 Satellite(1) 134

Lesson 25 Satellite(2) 139