“Inventing the Future” & Basic Electronics • Storytelling alternatives • Triggers of innovation • Communications and rate of change • Power = voltage x current • AC vs DC • Transformer • Vacuum tubes • Solid state electronics Burk’s Eight Primary Technological Developments • Nuclear power • Telecommunications • Computer • Assembly line • Jet engine/Air Transport • Plastics/Synthetic polymers • Liquid fuel rockets • Television Storytelling Alternatives • Heroic treatment of history • Thematic treatment of history • Periodic treatment of history Heroic Treatment of History • Assesses history based on special persons – However, no individual is responsible for an invention. – Denies involvement of humbler members of society whose contributions made the inventor successful. Thematic Treatment of History • Based on subjects such as computers, telecommunication, etc. • However, this neglects the interrelation of different subjects. • Naively implies a degree of foreknowledge. Periodic Treatment of History • Chronological approach to history based on definite time periods • Oversimplified • Developments do not normally occur in linear fashion. Triggers of Innovation • Deliberate attempts • Unexpected discovery • Unrelated developments • War and Religion • Accidents & unforeseen circumstances • Weather Deliberate attempts to develop • Soc. For the Encouragement of Nat’l Ind. • The electric light bulb • Kinetoscope • Von Linde’s refrigeration system Unexpected discovery through experimentation • Looking for one thing and finding something new. • Perkin’s synthetic dye or Guericke’s electricity • Oersted’s unexpected electromagnet • Moissan’s calcium carbide fertilizer, acetylene Unrelated Developments (“Connections”) • New technology from old technology • Pegged cylinder Bouchon’s perforated paper programming the computer • Weaving tech. cheap linen paper • Wilson’s cloud chamber splitting the atom War and Religion • Cannon Defensive Architecture, map making • The need for timely praying alarm clock Accidents & Unforeseen Circumstances • Decline of acetylene market cheap fertilizer • Explosion of the Earl’s coal kiln coal gas • Compass needle from China magnetism • Failure to pump mines barometer Physical and Climate Conditions • “Little Ice Age” chimney • malaria ice making machine • Reclamation of Europe modern plough Summarizing • No inventor works alone • Rate of technology change is proportional to rate of information exchange (communication) – Medieval Ind. Revolution – 16th century specialization/democratization of knowledge via printing press – 19th century telecommunications – 20th century digital telecommunications Burke’s Alternatives to Cope with Increasing Rate of Change? • Scrap all technology and go rural. • Selective research only. • Stop R&D and share out existing technology • Keep going the way have. Stop, scrap advanced technology – “Go Rural.” • Many would not survive. • This scenario is highly unlikely. • USA’s technology developments are most responsible for its wealth and world leadership. Selective research only • Assess science and technology strictly according to it societal worth. • Curtail other “unworthy” research. – Who decides where to focus efforts? • Nevertheless, governments do provide some tax incentives & subsidies to selectively stimulate development. Share out existing technology to 3rd world countries. • Produce more durable goods & less planned obsolescence. – How do you convince the haves that they have had enough? – Who’s going to pay for this transfer? • This does go on where private industry seeks advantage to sharing technology. – Investments into China, India, E. Europe, etc. Keep going the way we always have. • The most likely and probable scenario. “Science and technology has immeasurably enriched our material lives”. James Burke Alternating Current vs. Direct • Alternating current (AC) is generated at the power plant – USA voltage fluctuates 60 cycles per second (hertz) between + & - extremes as a sine wave. Europe 50 hertz. • Direct current (DC) comes from a battery, fuel cell or solar cell and does not fluctuate. The Power Grid Why AC & Not DC • Large electrical generators happen to generate AC. • Transformers must have AC to work. • Its easy to change AC to DC but difficult and costly to change DC to AC. Electricity • Power = current x voltage watts = amps x volts • Using the analogy of a garden hose: – Voltage is like the water pressure – Current is like the amount of water delivered. •Resistance (ohms) = volts/amps –Resistance is inversely proportional to the hose or wire diameter. Advantages of High Voltage • Powerloss = resistance x current2 – Since voltage and current are inversely proportional high voltage gets lower current thus less power loss through the power grid. • AC has the advantage over DC in that its voltage and current are easily modified with little power loss. Transformer • Increases or decreases alternating current • Transmission of high voltage AC results in lower power loss than low voltage. • With a transformer AC voltage can be increased/decreased with < 1% power loss • Power = current x voltage • Combination of Oersted and Faraday effect. • # coil turns is proportional to magnetic field & volts AC Transformer High Voltage 10,000 v Street voltage 1100 v Vin x Nout/Nin = Vout Your house 110 v AC Transformer Vin x Nout/Nin = Vout 110v x 10/5 = 220v Now flowing in the opposite direction 220v x 5/10 = 110v Westinghouse vs. Edison • Tesla argued for AC power grid. • Edison argued for DC power grid. – Electrocuted animals with AC to demonstrate its dangers. – Triggered the electric chair • Tesla/Westinghouse won. Vacuum Tube • Aka Thermionic Valves • Two electrodes (diode) control flow of current. – Hot cathode, emits electrons – Anode, accepts electrons • Three electrode tube is triode. – Used as electrode switch or amplifier in radios. • Third electrode in triode is a grid controlling electron flow to the anode. Diode Triode Anode Rectifier • Allows current flow in one direction only. • Diode used to convert AC to DC. • Diode used to filter out carrier signal in radio transmissions. Transistor • Solid state switch. Replaced most vacuum tubes in the 1960s. • Boron or Arsenic doped Silicon or Germanium junctions. • Smaller, lighter, rugged, longer life, more efficient and cheaper than vacuum tubes. • Ultimately replaced by the Integrated Circuit (IC). • Making an IC Silicon • Silicon comprises about 15% of our planet Earth. • Normally found as silicates. • It is a metaloid element exhibiting some metalic and some nonmetallic qualities. • Si has 4 valence electrons like Carbon and other elements in its group. Solid State Diodes • Silicon can be doped with other elements to affect it conductivity. • P and As have an extra valence electron while Boron has a vacant valence orbital. • Current will flow from N side to the P side not the reverse. • N side is cathode and P side is anode. Boron doped side is electron deficient Arsenic doped side is electron rich In reverse biased no current flows Moore’s Law • Gordon Moore (Intel) stated in 1965 that the number of transistors on a chip could double every 24 months. • Since then his statement has become the benchmark for the industry. Light Emitting Diodes (LEDs) • These are solid state lights. • Electrons from the higher energy N side drop at the junction to lower energy p side. • Giving off the energy as light particles (photons). Lasers • "light amplification by stimulated emission of radiation” • Emits light with spatial coherence • Semiconductor lasers Nanotechnology Carbon Nanotube Transistor Fossil Fuels • Petroleum, coal and gas. The U.S. is very dependant these fuel sources. • Coal comes from anaerobic decomposition of plant material • Petroleum (oil) comes from anaerobic decomposition of marine life. • Natural gas comes from both. California’s Power Sources Nuclear 22% Geothermal Wind 11% 3% Other Renewables 4% Coal 18% Natural Gas 33% Large Hydroelectric 9% Acid Rain • Industrial production of carbon, sulfur and nitrogen oxides beyond the levels which nature can consume is pollution. • Acid rain is caused by sulfur and nitrogen oxides in the air. These kill plants and fresh water marine animals. What you should know • Major technological developments according to Burke • #2 • The six triggers of innovation and examples of each. • #7-13 • Explain why rate of innovation is proportional to rate of information exchange. • #14 information exchange is directly proportional to innovation. • What are Burke’s ideas to cope with the increasing rate technology change. • #15-19 What you should know • How a transformer works • 1000 volts and 2 amps enters a transformer with 10 coils and exits with 20 coils. What is the exit voltage and amperage? How does the wattage change? • What does a diode do and how does it work? Explain the vacuum tube and transistor. • Explain what a triode is, how it works and what it may be used for in electronic equipment. • #26-28 • #26-28 • #30-35 • #30 & 32 What you should know • What is the difference between direct and alternating current? • #33 and lecture notes. AC is double polarity (sine wave) and DC is one polarity. • Why AC, not DC is used to • AC voltage exits the generator transmit electricity over high and its voltage is easily and voltage lines. efficiently changed. • What is Acid Rain? • #40 • Which side of the LED may be doped with phosphorus? • The N side #36