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Batteryless Radio
A batteryless radio is a type of radio receiver that does not require the use of a battery (electricity), battery to provide it with electrical power. Originally this referred to units which could be used directly by AC mains supply (mains radio); it can also refer to units which do not require a power source at all, except for the power that they receive from an ambient radio source, such as radio waves. History The earliest amplifying radios, vacuum tube radios, used Electric battery, batteries until the mid to late 1920s. The line-operated vacuum tube receiver was invented in 1925 by Edward S. Rogers, Sr. The unit operated with five Rogers vacuum tube#AC power, AC vacuum tubes and the Rogers battery eliminator, Battery-Eliminator Power Unit (power supply). This unit was later marketed for $120 as "Type 120". He established the Toronto station CFRB (an abbreviation of ''Canada's First Rogers Batteryless'') to promote sales of the product. Batteryless radios were not introdu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Clockwork Radio
Human power is the rate of work (physics), work or energy that is produced from the human body. It can also refer to the power (physics), power (rate of work per time) of a human. Power comes primarily from List of skeletal muscles of the human body, muscles, but Thermoregulation, body heat is also used to do work like warming Shelter (building), shelters, food, or other humans. World records of power performance by humans are of interest to work planners and workflow, work-process engineers. The average level of human power that can be maintained over a certain duration of time is interesting to engineers designing work operations in industry. Human-powered transport includes bicycles, rowing, skiing and many other forms of mobility. Human-powered equipment is occasionally used to generate, and sometimes to store, electrical energy for use where no other source of power is available. These include the Gibson girl survival radio, wind-up or (clockwork) radio and pedal radio. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thermocouple
A thermocouple, also known as a "thermoelectrical thermometer", is an electrical device consisting of two dissimilar electrical conductors forming an electrical junction. A thermocouple produces a temperature-dependent voltage as a result of the Seebeck effect, and this voltage can be interpreted to measure temperature. Thermocouples are widely used as list of temperature sensors, temperature sensors. Commercial thermocouples are inexpensive, interchangeable, are supplied with standard Electrical connector, connectors, and can measure a wide range of temperatures. In contrast to most other methods of temperature measurement, thermocouples are self-powered and require no external form of excitation. The main limitation with thermocouples is accuracy; system errors of less than one degree Celsius (°C) can be difficult to achieve. Thermocouples are widely used in science and industry. Applications include temperature measurement for kilns, gas turbine exhaust, diesel engines, and o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Transistor
A transistor is a semiconductor device used to Electronic amplifier, amplify or electronic switch, switch electrical signals and electric power, power. It is one of the basic building blocks of modern electronics. It is composed of semiconductor material, usually with at least three terminal (electronics), terminals for connection to an electronic circuit. A voltage or Electric current, current applied to one pair of the transistor's terminals controls the current through another pair of terminals. Because the controlled (output) power can be higher than the controlling (input) power, a transistor can amplify a signal. Some transistors are packaged individually, but many more in miniature form are found embedded in integrated circuits. Because transistors are the key active components in practically all modern electronics, many people consider them one of the 20th century's greatest inventions. Physicist Julius Edgar Lilienfeld proposed the concept of a field-effect transisto ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Radio Wave
Radio waves (formerly called Hertzian waves) are a type of electromagnetic radiation with the lowest frequencies and the longest wavelengths in the electromagnetic spectrum, typically with frequencies below 300 gigahertz (GHz) and wavelengths greater than , about the diameter of a grain of rice. Radio waves with frequencies above about 1 GHz and wavelengths shorter than 30 centimeters are called microwaves. Like all electromagnetic waves, radio waves in vacuum travel at the speed of light, and in the Earth's atmosphere at a slightly lower speed. Radio waves are generated by charged particles undergoing acceleration, such as time-varying electric currents. Naturally occurring radio waves are emitted by lightning and astronomical radio source, astronomical objects, and are part of the blackbody radiation emitted by all warm objects. Radio waves are generated artificially by an electronic device called a transmitter, which is connected to an antenna (radio), antenna, w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
School Of The Air
School of the Air is a generic term for correspondence schools catering for the primary and early secondary education of children in remote and outback Australia where some or all classes were historically conducted by radio, although this is now replaced by telephone and internet technology. In these areas, the school-age population is too small for a conventional school to be viable. History Circa 1929, Alfred Traeger invented the pedal radio which allowed people in remote areas to communicate over long distances, reducing their social isolation. One important use of the technology was to receive medical advice or summon a doctor by contacting the Royal Flying Doctor Service. Educator Adelaide Miethke realised the same technology could be used for by teachers to deliver lessons to students in remote locations, leading to the establishment of School of the Air. The first School of the Air lessons were officially delivered from the Royal Flying Doctor Service base in Alic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Royal Flying Doctor Service
The Royal Flying Doctor Service (RFDS), commonly known as the Flying Doctor, is an aeromedical retrieval service in Australia and the largest of its kind in the world. It is a non-profit organisation that provides urgent and emergency medical transport for patients in rural and remote areas of Australia who require transfer to a higher level of care (such as a tertiary referral hospital). RFDS also provides primary health care services such as general practice, mental health and allied health to remote communities who would otherwise have limited access. The RFDS comprises six autonomous regional organisations (such as the RFDS Queensland Section) and a federation office in Canberra. History "Mantle of safety" John Flynn had worked in rural and remote areas of Victoria and was commissioned by the Presbyterian Church to look at the needs of people living in the outback. His report to the Presbyterian Assembly in 1912 resulted in the establishment of the Australian Inla ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Solar Energy
Solar energy is the radiant energy from the Sun's sunlight, light and heat, which can be harnessed using a range of technologies such as solar electricity, solar thermal energy (including solar water heating) and solar architecture. It is an essential source of renewable energy, and its technologies are broadly characterized as either passive solar or active solar depending on how they capture and distribute solar energy or convert it into solar power. Active solar techniques include the use of photovoltaic systems, concentrated solar power, and solar water heating to harness the energy. Passive solar techniques include designing a building for better daylighting (architecture), daylighting, selecting materials with favorable thermal mass or light-dispersing properties, and organizing spaces that ventilation (architecture), naturally circulate air. In 2011, the International Energy Agency said that "the development of affordable, inexhaustible and clean solar energy technolo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Crank (mechanism)
A crank is an arm attached at a right angle to a rotating shaft by which circular motion is imparted to or received from the shaft. When combined with a connecting rod, it can be used to convert circular motion into reciprocating motion, or vice versa. The arm may be a bent portion of the shaft, or a separate arm or disk attached to it. Attached to the end of the crank by a pivot is a rod, usually called a connecting rod (conrod). The term often refers to a human-powered crank which is used to manually turn an axle, as in a bicycle crankset or a brace and bit drill. In this case a person's arm or leg serves as the connecting rod, applying reciprocating force to the crank. There is usually a bar perpendicular to the other end of the arm, often with a freely rotatable handle or pedal attached. Examples Familiar examples include: Hand-powered cranks * Spinning wheel * Mechanical pencil sharpener * Fishing reel and other reels for cables, wires, ropes, etc. *Starti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Clockwork Radio
Human power is the rate of work (physics), work or energy that is produced from the human body. It can also refer to the power (physics), power (rate of work per time) of a human. Power comes primarily from List of skeletal muscles of the human body, muscles, but Thermoregulation, body heat is also used to do work like warming Shelter (building), shelters, food, or other humans. World records of power performance by humans are of interest to work planners and workflow, work-process engineers. The average level of human power that can be maintained over a certain duration of time is interesting to engineers designing work operations in industry. Human-powered transport includes bicycles, rowing, skiing and many other forms of mobility. Human-powered equipment is occasionally used to generate, and sometimes to store, electrical energy for use where no other source of power is available. These include the Gibson girl survival radio, wind-up or (clockwork) radio and pedal radio. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Australia
Australia, officially the Commonwealth of Australia, is a country comprising mainland Australia, the mainland of the Australia (continent), Australian continent, the island of Tasmania and list of islands of Australia, numerous smaller islands. It has a total area of , making it the list of countries and dependencies by area, sixth-largest country in the world and the largest in Oceania. Australia is the world's flattest and driest inhabited continent. It is a megadiverse countries, megadiverse country, and its size gives it a wide variety of landscapes and Climate of Australia, climates including deserts of Australia, deserts in the Outback, interior and forests of Australia, tropical rainforests along the Eastern states of Australia, coast. The ancestors of Aboriginal Australians began arriving from south-east Asia 50,000 to 65,000 years ago, during the Last Glacial Period, last glacial period. By the time of British settlement, Aboriginal Australians spoke 250 distinct l ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pedal Radio
Human power is the rate of work or energy that is produced from the human body. It can also refer to the power (rate of work per time) of a human. Power comes primarily from muscles, but body heat is also used to do work like warming shelters, food, or other humans. World records of power performance by humans are of interest to work planners and work-process engineers. The average level of human power that can be maintained over a certain duration of time is interesting to engineers designing work operations in industry. Human-powered transport includes bicycles, rowing, skiing and many other forms of mobility. Human-powered equipment is occasionally used to generate, and sometimes to store, electrical energy for use where no other source of power is available. These include the Gibson girl survival radio, wind-up or (clockwork) radio and pedal radio. Available power Normal human metabolism produces heat at a basal metabolic rate of around 80 watts. During a bicycle race, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kerosene Lamp
A kerosene lamp (also known as a paraffin lamp in some countries) is a type of lighting device that uses kerosene as a fuel. Kerosene lamps have a wick or mantle as light source, protected by a glass chimney or globe; lamps may be used on a table, or hand-held lanterns may be used for portable lighting. Like oil lamps, they are useful for lighting without electricity, such as in regions without rural electrification, in electrified areas during power outages, at campsites, and on boats. There are three types of kerosene lamp: flat-wick, central-draft (tubular round wick), and mantle lamp. Kerosene lanterns meant for portable use have a flat wick and are made in dead-flame, hot-blast, and cold-blast variants. Pressurized kerosene lamps use a gas mantle; these are known as Petromax, Tilley lamps, or Coleman lamps, among other manufacturers. They produce more light per unit of fuel than wick-type lamps, but are more complex and expensive in construction and more complex to oper ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
