telephone
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HW. 4.1 Physics *Telephone 1) History Credit for the invention of the electric telephone is frequently disputed, and new controversies over the issue have arisen from time to time. As with other influential inventions such as radio, television, the light bulb, and the computer, there were several inventors who did pioneering experimental work onvoice transmission over a wire and improved on each other's ideas. Innocenzo Manzetti, Antonio Meucci, Johann Philipp Reis, Elisha Gray, Alexander Graham Bell, and Thomas Edison, among others, have all been credited with pioneering work on the telephone. An undisputed fact is that Alexander Graham Bell was the first to be awarded a patent for the electric telephone by the United States Patent and Trademark Office (USPTO) in March 1876. That first patent by Bell was the master patent of the telephone, from which other patents for electric telephone devices and features flowed. The early history of the telephone became and still remains a confusing morass of claims and counterclaims, which were not clarified by the large number of lawsuits that hoped to resolve the patent claims of many individuals and commercial competitors. The Bell and Edison patents, however, were forensically victorious and commercially decisive. A Hungarian engineer, Tivadar Puskás, quickly invented the telephone switchboard in 1876, which allowed for the formation of telephone exchanges, and eventually networks. 2) A telephone, or phone, is a telecommunications device that converts sound, typically the human voice, into electronic signals suitable fortransmission via cables or other transmission media over long distances. First patented in 1876 by Alexander Graham Bell and further developed by many others, the telephone was the first device in human history that enabled people to talk directly with each other across large distances. It rapidly became indispensable to businesses, government, and households, and it is now among the most widely used appliances in the developed world. The word telephone" has been adapted into the vocabulary of many languages. It is derived from the Greek: τῆλε, tēle, far and φωνή, phōnē, voice, together meaning distant voice. The essential elements of a telephone are a microphone (transmitter) to speak into and an earphone (receiver) which reproduces the voice of the distant person. In addition, most telephones contain a ringer which produces a sound to alert the user when a telephone call is coming in, and a dial used to enter a telephone number when initiating a call to another telephone. Until approximately the 1970s most telephones used a manual rotary dial, which was superseded by the modern Touch-Tone push-button dial, first introduced by AT&T in 1963. The receiver and transmitter are usually built into ahandset which is held up to the ear and mouth during conversation. The dial may be located either on the handset, or on a base unit to which the handset is connected by a cord containing wires.
3) Parts and Function Early telephones were technically diverse. Some used a liquid transmitter, some had a metal diaphragm that induced current in an electromagnet wound around a permanent magnet, and some were "dynamic" - their
diaphragm vibrated a coil of wire in the field of a permanent magnet or the coil vibrated the diaphragm. The sound-powered dynamic kind survived in small numbers through the 20th century in military and maritime applications, where its ability to create its own electrical power was crucial. Most, however, used the Edison/Berliner carbon transmitter, which was much louder than the other kinds, even though it required aninduction coil which was an impedance matching transformer to make it compatible with the impedance of the line. The Edison patents kept the Bell monopoly viable into the 20th century, by which time the network was more important than the instrument. Early telephones were locally powered, using either a dynamic transmitter or by the powering of a transmitter with a local battery. One of the jobs of outside plant personnel was to visit each telephone periodically to inspect the battery. During the 20th century, "common battery" operation came to dominate, powered by "talk battery" from the telephone exchange over the same wires that carried the voice signals. Early telephones used a single wire for the subscriber's line, with ground return used to complete the circuit (as used in telegraphs). The earliest dynamic telephones also had only one port opening for sound, with the user alternately listening and speaking (or rather, shouting) into the same hole. Sometimes the instruments were operated in pairs at each end, making conversation more convenient but also more expensive. At first, the benefits of a telephone exchange were not exploited. Instead telephones were leased in pairs to a subscriber, who had to arrange for a telegraph contractor to construct a line between them, for example between a home and a shop. Users who wanted the ability to speak to several different locations would need to obtain and set up three or four pairs of telephones. Western Union, already using telegraph exchanges, quickly extended the principle to its telephones in New York City and San Francisco, and Bell was not slow in appreciating the potential. Signalling began in an appropriately primitive manner. The user alerted the other end, or the exchange operator, by whistling into the transmitter. Exchange operation soon resulted in telephones being equipped with a bell in a ringer box, first operated over a second wire, and later over the same wire, but with a condenser (capacitor) in series with the bell coil to allow the AC ringer signal through while still blocking DC (keeping the phone "on hook"). Telephones connected to the earliest Strowger automatic exchanges had seven wires, one for the knife switch, one for each telegraph key, one for the bell, one for the push-button and two for speaking. Large wall telephones in the early 20th century usually incorporated the bell, and separate bell boxes for desk phones dwindled away in the middle of the century. Rural and other telephones that were not on a common battery exchange had a magneto or hand-cranked generator to produce a high voltage alternating signal to ring the bells of other telephones on the line and to alert the operator. Some local farming communities that were not connected to the main networks set upbarbed wire telephone lines that exploited the existing system of field fences to transmit the signal. *Cell Phone A device that can make and receive telephone calls over a radio link while moving around a wide geographic area. It does so by connecting to a cellular network provided by a mobile phone operator, allowing access to the public telephone network. By contrast, a cordless telephone is used only within the short range of a single, private base station. In addition to telephony, modern mobile phones also support a wide variety of other services such as text messaging, MMS, email, Internet access, short-range wireless communications (infrared, Bluetooth), business
applications, gaming and photography. Mobile phones that offer these and more general computing capabilities are referred to as smartphones.
*Wireless Communications The transfer of information between two or more points that are not connected by an electrical conductor. The most common wireless technologies use electromagnetic wireless telecommunications, such as radio. With radio waves distances can be short, such as a few metres for television remote control, or as far as thousands or even millions of kilometres for deep-space radio communications. It encompasses various types of fixed, mobile, and portable applications, including two-way radios, cellular telephones, personal digital assistants (PDAs), and wireless networking. Other examples of applications of radio wireless technology include GPS units, garage door openers, wireless computer mice,keyboards and headsets, headphones, radio receivers, satellite television, broadcast television and cordless telephones. Less common methods of achieving wireless communications include the use of light, sound, magnetic, or electric fields.
(May Nakalagay Dito yung name and something )
Three people were dead while 5 others were injured during a fire at the corner of the taft Avenue and Pedro Gil, last night.
The Grande Apartelle was reported in fire that start 11 pm last night at the third floor of the apartelle, the fire spread up to the seventh floor before the fire fighter announce it was under control at 4:30 am. The reason still unknown.
The dead bodies of Mildred Haro, 59 years old; Wilie Nogero, 76 years old; and Pearly Perez, 47 years old, were found at the fourth floor where the victims stay.
Five other persons were injured and one of them is a firefighter who suffered from suffocation. Three are still treated at the PGH while the other two were already released. Their identity is still unknown.
According to Fire Chief Roberto Rico Roberto Rico, this was the biggest fire the city had for the past ten years which need a big number of fire fighters that include those who are off-duty. He said that even though the fire was big and can’t be controlled when they arrived, they were able to enter the building able to help the residents and luckily the sixth and the seventh floor was empty that lessen the loss of lives.
The apartelle was open since 1935 and now it was burned, the residents don’t know what to do including the 76 years old widow Nora Cortez who said she doesn’t have anyone but her friends who also live in the burned apartelle.
3) Parts and Function Early telephones were technically diverse. Some used a liquid transmitter, some had a metal diaphragm that induced current in an electromagnet wound around a permanent magnet, and some were "dynamic" - their
diaphragm vibrated a coil of wire in the field of a permanent magnet or the coil vibrated the diaphragm. The sound-powered dynamic kind survived in small numbers through the 20th century in military and maritime applications, where its ability to create its own electrical power was crucial. Most, however, used the Edison/Berliner carbon transmitter, which was much louder than the other kinds, even though it required aninduction coil which was an impedance matching transformer to make it compatible with the impedance of the line. The Edison patents kept the Bell monopoly viable into the 20th century, by which time the network was more important than the instrument. Early telephones were locally powered, using either a dynamic transmitter or by the powering of a transmitter with a local battery. One of the jobs of outside plant personnel was to visit each telephone periodically to inspect the battery. During the 20th century, "common battery" operation came to dominate, powered by "talk battery" from the telephone exchange over the same wires that carried the voice signals. Early telephones used a single wire for the subscriber's line, with ground return used to complete the circuit (as used in telegraphs). The earliest dynamic telephones also had only one port opening for sound, with the user alternately listening and speaking (or rather, shouting) into the same hole. Sometimes the instruments were operated in pairs at each end, making conversation more convenient but also more expensive. At first, the benefits of a telephone exchange were not exploited. Instead telephones were leased in pairs to a subscriber, who had to arrange for a telegraph contractor to construct a line between them, for example between a home and a shop. Users who wanted the ability to speak to several different locations would need to obtain and set up three or four pairs of telephones. Western Union, already using telegraph exchanges, quickly extended the principle to its telephones in New York City and San Francisco, and Bell was not slow in appreciating the potential. Signalling began in an appropriately primitive manner. The user alerted the other end, or the exchange operator, by whistling into the transmitter. Exchange operation soon resulted in telephones being equipped with a bell in a ringer box, first operated over a second wire, and later over the same wire, but with a condenser (capacitor) in series with the bell coil to allow the AC ringer signal through while still blocking DC (keeping the phone "on hook"). Telephones connected to the earliest Strowger automatic exchanges had seven wires, one for the knife switch, one for each telegraph key, one for the bell, one for the push-button and two for speaking. Large wall telephones in the early 20th century usually incorporated the bell, and separate bell boxes for desk phones dwindled away in the middle of the century. Rural and other telephones that were not on a common battery exchange had a magneto or hand-cranked generator to produce a high voltage alternating signal to ring the bells of other telephones on the line and to alert the operator. Some local farming communities that were not connected to the main networks set upbarbed wire telephone lines that exploited the existing system of field fences to transmit the signal. *Cell Phone A device that can make and receive telephone calls over a radio link while moving around a wide geographic area. It does so by connecting to a cellular network provided by a mobile phone operator, allowing access to the public telephone network. By contrast, a cordless telephone is used only within the short range of a single, private base station. In addition to telephony, modern mobile phones also support a wide variety of other services such as text messaging, MMS, email, Internet access, short-range wireless communications (infrared, Bluetooth), business
applications, gaming and photography. Mobile phones that offer these and more general computing capabilities are referred to as smartphones.
*Wireless Communications The transfer of information between two or more points that are not connected by an electrical conductor. The most common wireless technologies use electromagnetic wireless telecommunications, such as radio. With radio waves distances can be short, such as a few metres for television remote control, or as far as thousands or even millions of kilometres for deep-space radio communications. It encompasses various types of fixed, mobile, and portable applications, including two-way radios, cellular telephones, personal digital assistants (PDAs), and wireless networking. Other examples of applications of radio wireless technology include GPS units, garage door openers, wireless computer mice,keyboards and headsets, headphones, radio receivers, satellite television, broadcast television and cordless telephones. Less common methods of achieving wireless communications include the use of light, sound, magnetic, or electric fields.
(May Nakalagay Dito yung name and something )
Three people were dead while 5 others were injured during a fire at the corner of the taft Avenue and Pedro Gil, last night.
The Grande Apartelle was reported in fire that start 11 pm last night at the third floor of the apartelle, the fire spread up to the seventh floor before the fire fighter announce it was under control at 4:30 am. The reason still unknown.
The dead bodies of Mildred Haro, 59 years old; Wilie Nogero, 76 years old; and Pearly Perez, 47 years old, were found at the fourth floor where the victims stay.
Five other persons were injured and one of them is a firefighter who suffered from suffocation. Three are still treated at the PGH while the other two were already released. Their identity is still unknown.
According to Fire Chief Roberto Rico Roberto Rico, this was the biggest fire the city had for the past ten years which need a big number of fire fighters that include those who are off-duty. He said that even though the fire was big and can’t be controlled when they arrived, they were able to enter the building able to help the residents and luckily the sixth and the seventh floor was empty that lessen the loss of lives.
The apartelle was open since 1935 and now it was burned, the residents don’t know what to do including the 76 years old widow Nora Cortez who said she doesn’t have anyone but her friends who also live in the burned apartelle.
