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Battery Eliminator
A battery eliminator is a device powered by an electrical source other than a battery, which then converts the source to a suitable DC voltage that may be used by a second device designed to be powered by batteries. A battery eliminator does away with the need to replace batteries but may remove the advantage of portability. A battery eliminator is also effective in replacing obsolete battery designs. Some examples of battery eliminators include the nine-volt mains power supply, the size and shape of a PP12 battery, originally intended to replace the battery in portable radios in the 1960s. A solar panel providing power for a portable appliance may also be considered a battery eliminator. The term is also sometimes used as a misnomer when using a bigger battery for more runtime when branching out a power supply to wired electrical equipment using DC input. History Early commercial battery eliminators were produced by the Edward S. Rogers, Sr. company in 1925 as a complement t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anode
An anode is an electrode of a polarized electrical device through which conventional current enters the device. This contrasts with a cathode, an electrode of the device through which conventional current leaves the device. A common mnemonic is ACID, for "anode current into device". The direction of conventional current (the flow of positive charges) in a circuit is opposite to the direction of electron flow, so (negatively charged) electrons flow from the anode of a galvanic cell, into an outside or external circuit connected to the cell. For example, the end of a household battery marked with a "+" is the cathode (while discharging). In both a galvanic cell and an electrolytic cell, the anode is the electrode at which the oxidation reaction occurs. In a galvanic cell the anode is the wire or plate having excess negative charge as a result of the oxidation reaction. In an electrolytic cell, the anode is the wire or plate upon which excess positive charge is imposed. A ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Traction Battery
An electric vehicle battery (EVB, also known as a traction battery) is a rechargeable battery used to power the electric motors of a battery electric vehicle (BEV) or hybrid electric vehicle (HEV). Typically lithium-ion batteries, they are specifically designed for high electric charge (or energy) capacity. Electric vehicle batteries differ from starting, lighting, and ignition (SLI) batteries as they are designed to give power over sustained periods of time and are deep-cycle batteries. Batteries for electric vehicles are characterized by their relatively high power-to-weight ratio, specific energy and energy density; smaller, lighter batteries are desirable because they reduce the weight of the vehicle and therefore improve its performance. Compared to liquid fuels, most current battery technologies have much lower specific energy, and this often impacts the maximum all-electric range of the vehicles. The most common battery type in modern electric vehicles are lithium-ion a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Radio-controlled Model
A radio-controlled model (or RC model) is a model that is steerable with the use of radio control. All types of model vehicles have had RC systems installed in them, including ground vehicles, boats, planes, helicopters and even submarines and scale railway locomotives. History Radio control has been around since Nikola Tesla demonstrated a remote control boat in 1898. World War II saw increased development in radio control technology. The Luftwaffe used controllable winged bombs for targeting Allied ships. During the 1930s the Good brothers Bill and Walt pioneered vacuum tube based control units for R/C hobby use. Their "Guff" radio controlled plane is on display at the National Aerospace museum. Ed Lorenze published a design in Model Airplane News that was built by many hobbyists. Later, after WW2, in the late 1940s to mid 1950 many other R/C designs emerged and some were sold commercially, Berkeley's Super Aerotrol, was one such example. Originally simple 'on-off' syst ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Battery Eliminator Circuit
In battery-powered equipment, a battery eliminator circuit (BEC) is an electronic voltage regulator used to power a subsystem at a different voltage without the need for a supplemental battery. BECs are commonly used in radio-controlled models, which need separate voltages to power the motor and the R/C equipment. Radio-controlled (R/C) models In an electric-powered radio-controlled model, the BEC is typically part of the electronic speed control (ESC). BEC allows such a model to carry only one battery (the motive power battery) instead of two (motive power, and a separate battery to operate the R/C equipment). A BEC-equipped ESC meant for airplane use often incorporates a low-voltage-cutoff (LVC) circuit which can sense the voltage drop caused when the battery has little charge left. It then cuts the power to the 'drive' motor in order to provide the 'steering' servo(s) with enough power to be able to bring the model safely back to the operator. The power to the propeller ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Batteryless Switch
A wireless light switch is a light switch that commands a light or home appliance to turn itself off or on, instead of interrupting the power line going to the light fixture. There are different ways to communicate between the switch and the fixture: # Using radio transmission: A radio receiver is typically wired or screwed into a fixture or device, wired or otherwise connected to the electrical system of the building or plugged into an outlet. The radio receiver's memory is programmed by any number of means to respond to certain selected "switches" or (more correctly) remote control transmitters. # Using the existing power lines (such as INSTEON or X10): A receiver is plugged into an outlet and a device is then plugged into the receiver. The plug-in receiver is then programmed to the switches. Some devices are hard wired into ceiling light fittings, making for a hidden system. Common uses for wireless switches Complicated wiring Multiple wireless transmitters can command a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Batteryless Radio
A batteryless radio is a radio receiver which does not require the use of a 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 radio waves. History The line-operated vacuum tube receiver was invented in 1925 by Edward S. Rogers, Sr. The unit operated with 5 Rogers AC vacuum tubes and the Rogers 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 introduced into the United States until May 1926 and then into Europe in 1927. Crystal radio receivers are a very simple kind of batteryless radio receiver. They do not need a battery or power source, except for the power that ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Photographic Studio
A photographic studio is often a business owned and represented by one or more photographers, possibly accompanied by assistants and pupils, who create and sell their own and sometimes others’ photographs. Since the early years of the 20th century the business functions of a photographic studio have increasingly been called a photographic agency leaving the term "photographic studio" to refer almost exclusively to the workspace. The history of photographic studios and photography dates back to the 1840s with the invention of processes for recording camera pictures, by Henry Fox Talbot and Louis Daguerre. The earliest photographic studios made use of natural daylight to create photographic portraits. As already used by artists, a northern light with no direct sunlight was favoured. The first use of a "flash" dates back to 1839 when L. Ibbetson used limelight to photograph very small objects. Limelight was produced by placing a piece of lime into a flame fuelled with oxy-hydr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tripod
A tripod is a portable three-legged frame or stand, used as a platform for supporting the weight and maintaining the stability of some other object. The three-legged (triangular stance) design provides good stability against gravitational loads as well as horizontal shear forces, and better leverage for resisting tipping over due to lateral forces can be achieved by spreading the legs away from the vertical centre. Variations with one, two, and four legs are termed '' monopod'', ''bipod'', and ''quadripod'' (similar to a table). Etymology First attested in English in the early 17th century, the word ''tripod'' comes via Latin ''tripodis'' ( GEN of ''tripus''), which is the romanization of Greek (''tripous''), "three-footed" (GEN , ''tripodos''), ultimately from (''tri-''), "three times" (from , ''tria'', "three") + (''pous''), "foot". The earliest attested form of the word is the Mycenaean Greek , ''ti-ri-po'', written in Linear B syllabic script. Cultural use Many c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Battery Pack
A battery pack is a set of any number of (preferably) identical batteries or individual battery cells. They may be configured in a series, parallel or a mixture of both to deliver the desired voltage, capacity, or power density. The term battery pack is often used in reference to cordless tools, radio-controlled hobby toys, and battery electric vehicles. Components of battery packs include the individual batteries or cells, and the interconnects which provide electrical conductivity between them. Rechargeable battery packs often contain a temperature sensor, which the battery charger uses to detect the end of charging. Interconnects are also found in batteries as they are the part which connects each cell, though batteries are most often only arranged in series strings. When a pack contains groups of cells in parallel there are differing wiring configurations which take into consideration the electrical ''balance'' of the circuit. Battery regulators are sometimes used to keep ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Grid Bias
In electronics, biasing is the setting of DC (direct current) operating conditions (current and voltage) of an active device in an amplifier. Many electronic devices, such as diodes, transistors and vacuum tubes, whose function is processing time-varying ( AC) signals, also require a steady (DC) current or voltage at their terminals to operate correctly. This current or voltage is called ''bias''. The AC signal applied to them is superposed on this DC bias current or voltage. The operating point of a device, also known as bias point, quiescent point, or Q-point, is the DC voltage or current at a specified terminal of an active device (a transistor or vacuum tube) with no input signal applied. A bias circuit is a portion of the device's circuit which supplies this steady current or voltage. Overview In electronics, 'biasing' usually refers to a fixed DC voltage or current applied to a terminal of an electronic component such as a diode, transistor or vacuum tube in a cir ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vacuum Tube
A vacuum tube, electron tube, valve (British usage), or tube (North America), is a device that controls electric current flow in a high vacuum between electrodes to which an electric voltage, potential difference has been applied. The type known as a thermionic tube or thermionic valve utilizes thermionic emission of electrons from a hot cathode for fundamental electronic functions such as signal amplifier, amplification and current rectifier, rectification. Non-thermionic types such as a vacuum phototube, however, achieve electron emission through the photoelectric effect, and are used for such purposes as the detection of light intensities. In both types, the electrons are accelerated from the cathode to the anode by the electric field in the tube. The simplest vacuum tube, the diode (i.e. Fleming valve), invented in 1904 by John Ambrose Fleming, contains only a heated electron-emitting cathode and an anode. Electrons can only flow in one direction through the device—fro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
