By: Heber Ricardo Palala Dionicio
The history of mobile phones charts the development of devices which connect wirelessly to the public switched telephone network. The transmission of speech by radio has a long and varied history going back to Reginald Fessenden's invention and shore-to-ship demonstration of radio telephony, through the Second World War with military use of radio telephony links. Hand-held radio transceivers have been available since the 1940s. Mobile telephones for automobiles became available from some telephone companies in the 1940s. Early devices were bulky and consumed high power and the network supported only a few simultaneous conversations. Modern cellular networks allow automatic and pervasive use of mobile phones for voice and data communications.
Cell Phones Evolution
Alexander Graham Bell Alexander Graham Bell (March 3, 1847 – August 2, 1922) was an eminent scientist, inventor, engineer and innovator who is credited with inventing the first practical telephone. Bell's father, grandfather, and brother had all been associated with work on elocution and speech, and both his mother and wife were deaf, profoundly influencing Bell's life's work. His research on hearing and speech further led him to experiment with hearing devices which eventually culminated in Bell being awarded the first US patent for the telephone in 1876.In retrospect, Bell considered his most famous invention an intrusion on his real work as a scientist and refused to have a telephone in his study. Many other inventions marked Bell's later life, including groundbreaking work in optical telecommunications, hydrofoils and aeronautics. In 1888, Bell became one of the founding members of the National Geographic Society. He has been described as one of the most influential figures in human history.
Electrical telegraph An electrical telegraph is a telegraph that uses electrical signals, usually conveyed via telecommunication lines or radio. The electromagnetic telegraph is a device for human-to-human transmission of coded text messages. The electrical telegraph, or more commonly just 'telegraph', superseded optical semaphore telegraph systems, such as those designed by Claude Chappe for the French military, and Friedrich Clemens Gerke for the Prussian military, thus becoming the first form of electrical telecommunications. In a matter of decades after their creation, electrical telegraph networks permitted people and commerce to almost instantly transmit messages across both continents and oceans, with widespread social and economic impacts.
Electrical Telegraphs
Telephone Story 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 on voice 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.[2] 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 Puskรกs, quickly invented the telephone switchboard in 1876, which allowed for the formation of telephone exchanges, and eventually networks.
Advantages of cell phones Сеll-рhоnes have three principal advantages. Сеll рhоnes have made communication easier. In addition, Сеll рhоnes provide their users with extra devices in addition to telephone. At last, Сеll-рhоnes can provide safety for their users .Сеll рhоnes have become accepted in the last fifteen years because they have made communication easier. People can call each other no matter where they are. Fifteen years ago, there was no way to call someone who had no access to а conventional telephone.
Cell Phone Disadvantages The use of Сеll-рhоnes has been proven to be а big distraction. There are car accidents occurring everywhere due to the lack of attentiveness of drivers. Parents now think that it's better to buy Сеll-рhоnes for their new teen drivers fore emergencies, but do you really think that they are used for those only? And since Сеll-рhоnes are so fabulous, then why do you always get а busy, roaming signal and cause you to keep redialing а number till you finally get through to that person? After all that trouble you are normally bothered and frustrated .Things like these can created accidents and even death .The possibility of brain tumors is also increasing with the use of cellular phones. Radiation is enormously hazardous to Сеll рhоnes users. The more cell phone uses, the greater chances become for brain cancer. When Сеll-рhоnes first came out, people purchased them in case of emergencies. Now, people bring their.