Saturday, March 22, 2008

Cell Phone Batteries

All You Ever Wanted To Know About Cell Phone Batteries

Cell phones run on various kinds of batteries depending on the manufacturer, phone size or shape and features. There are basically four types of cell phone batteries: Lithium Polymer, Lithium Ion, Nickel Metal Hydride and Nickel Cadmium.

Lithium Polymer is the most recent type and applies the latest technology in DC power. This type of battery is light in weight and will not explode even if pierced. The battery elements are enclosed in platic pouches and do not have memory defects. They last about 50 times longer than Nickel Metal Hydride batteries.

Lithium Ion is also memory efficient and longer lasting than Nickel Metal Hydride batteries but they are quite lighter. They tend to be expensive and would only fit new models of phones. Most Lithium-ion batteries apply a fast charge technique to quickly charge up your cell phone up to 80% capacity and then slowly bring it up to full power in about two hours.

Nickel Metal Hydride is also memory efficient and lasts longer than the NIM type about 40 times. This type of battery is good for people who need rapid charging and if used with a car charger can be fully charged under 1 hour. The special formula permits the concentration of energy in a single pack – sometimes about twice the power of Nickel Cadmium. This type is preferred by a lot of mobile phone users because it lasts long and is cheap. Again, they are non-toxic and appeals to environmentalists.

Nickel Cadmium are the oldest type and has a lot of memory defects. Another severe disadvantage is that they will have to be totally discharged before you can charge them again otherwise you may irreversibly damage them. Again this type is highly toxic due to the presence of Nickel Cadmium and is gradually being phased out by cell phone manufacturers.

Batteries typically have 300 to 400 charge cycles in their life span. It is so because anytime you charge your battery, the battery loses away some of its potency and thus become diminished in power.

Cell phone batteries can be pretty expensive items if you consider the fact that a Nokia 3310 battery can cost up to $24.95. Here are a few tips to prolong the life of your battery:

1. Dont allow materials to get stuck on the terminals as that causes the battery to lose contact with the terminals resulting in improper connection.

2. Keep the batteries in a cool place and allow them to adjust to room temperature before charging as the sharp rise in temperature upon charging can damage them.

3. The life of your cell phone depends on the potency of your battery. Knowing how they operate and how to care for them can ensure that your cellular device runs and runs well for years.

Friday, March 21, 2008

The History Of Cellphones

Telefonos Moviles Just Began With Simple Telephones

Here, with the extract of the book THE HISTORY OF THE TELEPHONE by Herbert N. Casson, we show where moviles, cell phones and pdas began. In that somewhat distant year 1875, when the telegraph and the Atlantic cable were the most wonderful things in the world, a tall young professor of elocution was desperately busy in a noisy machine-shop that stood in one of the narrow streets of Boston, not far from Scollay Square. It was a very hot afternoon in June, but the young professor had forgotten the heat and the grime of the workshop. He was wholly absorbed in the making of a nondescript machine, a sort of crude harmonica with a clock-spring reed, a magnet, and a wire. It was a most absurd toy in appearance. It was unlike any other thing that had ever been made in any country. The young professor had been toiling over it for three years and it had constantly baffled him, until, on this hot afternoon in June, 1875, he heard an almost inaudible sound--a faint TWANG--come from the machine itself.

For an instant he was stunned. He had been expecting just such a sound for several months, but it came so suddenly as to give him the sensation of surprise. His eyes blazed with delight, and he sprang in a passion of eagerness to an adjoining room in which stood a young mechanic who was assisting him.

"Snap that reed again, Watson," cried the apparently irrational young professor. There was one of the odd-looking machines in each room, so it appears, and the two were connected by an electric wire. Watson had snapped the reed on one of the machines and the professor had heard from the other machine exactly the same sound. It was no more than the gentle TWANG of a clock-spring; but it was the first time in the history of the world that a complete sound had been carried along a wire, reproduced perfectly at the other end, and heard by an expert in acoustics.

That twang of the clock-spring was the first tiny cry of the newborn telephone, uttered in the clanging din of a machine-shop and happily heard by a man whose ear had been trained to recognize the strange voice of the little newcomer. There, amidst flying belts and jarring wheels, the baby telephone was born, as feeble and helpless as any other baby, and "with no language but a cry."

The professor-inventor, who had thus rescued the tiny foundling of science, was a young Scottish American. His name, now known as widely as the telephone itself, was Alexander Graham Bell. He was a teacher of acoustics and a student of electricity, possibly the only man in his generation who was able to focus a knowledge of both subjects upon the problem of the telephone. To other men that exceedingly faint sound would have been as inaudible as silence itself; but to Bell it was a thunder-clap. It was a dream come true.

It was an impossible thing which had in a flash become so easy that he could scarcely believe it. Here, without the use of a battery, with no more electric current than that made by a couple of magnets, all the waves of a sound had been carried along a wire and changed back to sound at the farther end. It was absurd. It was incredible. It was something which neither wire nor electricity had been known to do before. But it was true.

No discovery has ever been less accidental. It was the last link of a long chain of discoveries. It was the result of a persistent and deliberate search. Already, for half a year or longer, Bell had known the correct theory of the telephone; but he had not realized that the feeble undulatory current generated by a magnet was strong enough for the transmission of speech. He had been taught to undervalue the incredible efficiency of electricity. Nothing so far to the current PDAs and cell phones(moviles) that work without plug-in to the socket and last hours, days and even weeks.



Hello everybody,

Here you got an interesting site which gives you all info on cell phones.

Leave your comments and let me know your encouragements and critics.

Click here to start with the history of cell phones.