Posts Tagged ‘michael faraday’
October 19th, 2009 | 
Author: It’s hard to believe that just 15 years ago cell phones were a rarity. As soon back as 1990, if one could afford a cell phone device, you would be lucky to be able to afford the plan that came with it.
Yet today most communication is done via cell phones. Business is conducted, personal plans are made, and many parents rely on cell phone technology to keep their families safe and ease concerns of “what ifs.”
But the history of these seemingly must-have devices might be rather startling. Mobile phones that recognizable as the precursor to today’s modern cell phones have been around since the 1950s. In fact, Humphrey Bogart’s character Linus Larrabee in the 1954 film “Sabrina” uses a mobile phone in the back of his limousine.
Let’s take a brief look at the history of the cell phone and how it made the transition from awkward, hard-to-use chunks of plastic to today’s sleek, sophisticated cell phones models.
1865 – The first person to produce a technology similar to cell phones was Dr. Mahlon Loomis. An American dentist from Virginia, Dr. Loomis was the first person to send wireless communications. Dr. Loomis launched copper-fitted kites which acted as antennas, and, thanks to the ability to bounce signals off Earth’s atmosphere while using the kites as “signal boosters,” he was able to send a wireless telegraph signal 18 miles without the use of ground wires. Though no witness was present, Dr. Loomis was the first individual able to expand on the amazing advances in communications brought by Michael Faraday (who proved that space can conduct electricity) and Samuel Morse (who invented the telegraph, the world’s first device to send signals electronically).
1956 – Developed by Ericsson and released 1956, the first fully functioning cell phone was called the Mobile Telephone system A (MTA). The first model weighed 90 pound; a later version weighted 20 pounds. The business had 600 customers before it shut down in 1983.
1973 – Dr. Martin Cooper of Motorola unveiled the first analog mobile phone device. Called the Motorola DynaTAC 8000X, the early cell phone would later become available for the public in 1983. It weighed about 2 pounds, had 1 hour of battery life, and cost a hefty $4,000.
1982 – One year before the Motorola DynaTAC 8000X would be released, Nokia released their mobile device called the Mobira Senator. Designed for use in cars, the phone looked more like a boombox than today’s modern cell phone. Plus, it weighted quite a bit: 21 pounds to be exact.
Today, cell phones come in all shapes, sizes, and with any kind of feature you would need. From GPS locating technology to driving directions, cell phones can take your photo, fetch news headlines, and remember your loved ones’ birthdays. And with the rise of the iPhone and smartphone technology as seen in the recent Blackberry Storm, the availability and uses of cell phone applications are endless.
Before purchasing a cell phone, make sure to consider what you may need. You no longer have to settle on what will “just do.” Do you like snapping candid videos? Is a cell phone calendar an important tool for you? Or do you just want to send and receive calls and not worry about too many additional features?
But whether you need fancy features or just a calling device, at least picking up your new cell phone doesn’t mean you also need a gym membership – the average weight of today’s cell phones is 113 grams, compared to the 20-pound 1956 models.
Today’s overwhelming cell phone choices require the best options. To take a look at some of today’s hottest cell phone devices, minute plans, and accessories visit www.BetterCellPhoneDeals.com. You’ll be so glad you did!
Article Source: The History of Cell Phone Devices
HVAC&R – are the initials that stand for “heating, ventilating, air conditioning and refrigeration”. The abbreviation is sometimes also referred as a complete climate control system. The HVAC&R technology holds critical importance while designing medium to large sized corporate or industrial buildings where humidity and temperature need be maintained and regulated to ensure safe and comfortable environment within.
The function of heating, ventilating and air conditioning is based on the principles of thermodynamics, heat transfer and fluid mechanics. Resting on the base of inventions and discoveries made by well known scientists like Michael Faraday, James Joule, Willis Carrier and many others, the components of HVAC systems went hand-in-hands with the industrial revolution, higher efficiency, new methods of modernization and various system controls that are constantly introduced by companies and inventors all over the world.
Heating, ventilating, and air-conditioning are closely interrelated in their functions. All the three seek to provide required thermal comfort, ventilation, indoor air quality, and reasonable air conditioning maintenance and installation costs. In modern building designs the control systems of all these functions are integrated into one or more HVAC systems.
If the building size is small, then the building contractors normally size and select the heating ventilation and air conditioning systems for such buildings themselves. Whereas for larger buildings where the building permits and code compliance inspections of the installations are the norm, the structural designers and architectural engineers conduct a survey of the building and then analyze and design the HVAC systems for that building.
TAC Mechanical Services Ltd is a leading UK enterprise that provides guidance, sales and installation of top brand HVAC services including service and maintenance of domestic and commercial heating air-conditioning systems in all parts of UK.
Tac Services is a leading air conditioning supplier UK providing commercial & domestic air conditioning services with utmost customer satisfaction. Contact us for reliable air conditioning maintenance and air conditioning installation services.
Article Source: HVAC&R – A Complete Climate Control Acronym
Television sets or television is an invention of several scientists whose discoveries date back to 1831 when Joseph Henry and Michael Faraday discovered electromagnetism. Since that time, many scientists went through painstaking work to design a device that can produce both audio and visual images. The “tube” as we call them today, is a telecommunication device used to display electronic images transmitted by a television channel through radio waves. The term television comes from the Greek word “tele” meaning far, and Latin word “visio-n”, meaning sight.
Television sets has become part of modern living since its inception around the 1940’s. In the United States, around 98 subscribe to cable television. Aside from its entertainment purposes, television sets have become educational tools, as well as advertising media. The average American household watches television seven hours a day.
Television sets images are actually the end result of a three way communication process. From a source (say, television stations), broadcast elements travel through waves and then received by television sets’ transmitters. That’s how images are produced. Television images are composed of 525 horizontal lines shown on a screen.
Television sets elements
Television sets need to have a display device that converts electrical signals into light to form images. A sound device converts electrical signals into sound that goes along the images reproduced on the display device; built-in speakers make these converted sounds heard. A television receiver picks up broadcast signals from a television source while a transmitter is responsible in modulating image and sound information television signals.
Television sets technology
From black and white screens, to colored television screens, manufacturers recently produced wide screen television sets with theater quality. Although they are almost 10 times more expensive than the old colored screens, manufacturers claim the highest resolution and unprecedented image quality. Wide television screens begin at 27″ up to 60″. New technology television sets have four types: plasma, LCD, and rear projection CRT.
Plasma television sets cost around $1000-$4000. These TVs are digital with high resolutions. LCD TVs are similar to a screen of a laptop. They are much thinner (about an inch) than plasmas and screen sizes are limited to 40″ only.
Rear Projection CRTs have screen sizes 40″ or more. Rear projection CRTs are like a combination of a projector and screen into a TV set. They are relatively cheaper compared with other wide screen television sets but consumers would have to contend with the bulkiness of rear projection CRTs.
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Article Source: The Wonders of Television Sets
The phenomenon of electromagnetic induction was first discovered by Michael Faraday in 1831, and it is evident that he realised at least a part of its future potential in the modern world. A contemporary politician asked him about the usefulness of the discovery; he answered ‘at present I do not know, but one day you will be able to put a tax on it.’
The earliest record of using electromagnetic technology to locate buried cables dates from around 1910. More portable locators were made over the next years and the Sharman Main Finder was just one example. The user instructions give a tinge of envy to anyone trying to trace gas pipes .. ..’just clip the generator to a gas bracket in the nearest house or onto a street lamp.’
American and German schools of design emerged during the years leading up to the Second World War. In North America roads were wide and wide cables hung on poles so the main requirement for a locator was to locate widely spaced buried pipes. The result was a simple, high frequency, low power and low cost locator.
In Germany, cables as well as pipes were buried under narrow streets, so elaborate low frequency and high power locators were developed that required considerable expertise to obtain satisfactory results.
Dr Gerhard Fisher of California designed the Metallascope, the first high performance buried pipe and cable locating set. His system made use of the latest scientific developments and his company exists today and still produces the M-scope, an up-to-date descendent of the original Metallascope.
One of the engineering sections of Bell Laboratories studied the problem of accurate location of newly buried cables and recognised that an antenna with twin sensing aerials would give more positive plan definition, and also measure the depth of a target cable. The subsequent design, called the Depthometer, was engineered and manufactured in 1964. It was another 12 years before the first commercial twin aerial antenna locator was made by the Electrolocation company in Bristol England.
The twin aerial system was found to have substantial advantages over single aerial locators. Twin sensing aerials combined the seemingly contradictory qualities of discrimination with sensitivity. For the first time it was possible to locate buried cables below an overhead power line and to sort out crowded utility services under a city street intersection.
The introduction of the twin aerial antenna coupled with miniaturised electronic circuitry coincided with a programme of extending and upgrading utility distribution systems. This growing demand and technical progress resulted in a series of advances and new features to make locating more certain and more simple. Some of these advances included:
” Combination of active and passive signal reception
” Multi-frequency locating sets enabling the user to select the most suitable frequency for each application
” Electronic depth measurement.
” Current measurement along the length of a pipe or cable to detect coating or insulation defects.
” Current direction recognition to verify the identity of a target line.
” Permanently installed signal transmitters to apply a signal tone to a telephone cable over distances up to 150km/100 miles.
Today, electromagnetic locators are the worldwide standard for locating buried pipes and cables. A number of specialised manufacturers offer a choice of locators ranging from simple equipment used to detect the presence of buried cables to sophisticated instruments for pinpointing, identifying and fault finding buried pipes and cables in the most complex situations.
Written by Select Surveys, one of the UK’s leading independent surveying companies specialising in using electromagnetic, CAT and ground penetrating radar equipment to detect underground cables and utilities.
Article Source: A History of Underground Electromagnetic Surveying