Thursday, December 30, 2010

"The Story of Radio" from VOA




SHIRLEY GRIFFITH: I'm Shirley Griffith.STEVE EMBER: And I’m Steve Ember with EXPLORATIONS in VOA Special English. Today we tell about the history of radio and the latest technology.

(MUSIC)

SHIRLEY GRIFFITH: Our story begins in Britain in eighteen seventy-three. A scientist named James Maxwell wrote a mathematical theory about a kind of energy. He called this energy electromagnetic waves.

His theory said this kind of energy could pass unseen through the air. James Maxwell was not able to prove his idea. Other scientists could not prove it either until German scientist Heinrich Hertz tried an experiment around eighteen eighty-seven.

STEVE EMBER: Hertz’s experiment sounds very simple. He used two pieces of metal placed close together. He used electricity to make a spark jump between the two pieces of metal. He also built a simple receiver made of wire that was turned many times in a circle or looped. At the ends of the loop were small pieces of metal separated by a tiny amount of space. The receiver was placed several meters from the other device.

Heinrich Hertz proved that James Maxwell’s idea was correct. Electromagnetic waves or energy passed through the air from one device to the other.

SHIRLEY GRIFFITH: Later, Hertz demonstrated the experiment to his students in a classroom. One of the students asked what use might be made of this discovery. But Hertz thought his discovery was of no use. He said it was interesting but had no value.

He was wrong. His experiment was the very beginning of the electronic communications we use today. In recognition of his work, the unit of frequency of a radio wave, one cycle per second, is named the hertz.

STEVE EMBER: Radio waves became known to scientists as Hertzian Waves. But the experiment was still of no use until Guglielmo Marconi improved on the device that created Hertzian Waves. He began his experiments in Italy in eighteen ninety-four.

Guglielmo Marconi
loc.gov
Guglielmo Marconi

Marconi was soon able to transmit sound across a distance of several kilometers. He tried to interest Italian government officials in his discovery, but they were not interested.

Marconi traveled to Britain. His invention was well received there. In eighteen ninety-seven, he established the Wireless Telegraph and Signal Company. The company opened the world’s first radio factory in Chelmsford, England in eighteen ninety-eight.

(MUSIC)

SHIRLEY GRIFFITH: Very quickly, people began sending and receiving radio messages across long distances using equipment made by Marconi’s company.

Ships at sea needed the device. Before Marconi’s invention, they had no communication until they arrived in port. With radio, ships could call for help if they had trouble. They could send and receive information.

All of Marconi’s radios communicated using Morse code. An expert with Morse code could send and receive thirty or forty words a minute. Marconi’s radio greatly increased the speed of communications.

STEVE EMBER: On December twenty-fourth, nineteen-oh-six, radio operators on ships in the Atlantic Ocean near the American coast began hearing strange things. At first it was violin music. Then they heard a human voice. The voice said “Have a Merry Christmas.”

That voice belonged to a man named Reginald Fessenden. He had been working on producing a device that could transmit the human voice or music using radio. He decided to try it for the first time on December twenty-fourth. It was the first time a human voice had been heard on radio.

SHIRLEY GRIFFITH: Improvements in radio technology now came more quickly. Large companies became interested. Broadcasting equipment and radio receivers were improved.

Fourteen years after Reginald Fessenden’s voice was heard by radio operators at sea, the first real radio broadcast was transmitted. It came from the city of Pittsburgh, Pennsylvania.

The radio program was transmitted on radio station KDKA on the evening of November second, nineteen twenty. The man speaking on the radio was Leo Rosenberg. He was announcing the early results of the presidential election between James Cox and Warren Harding.

STEVE EMBER: Those first KDKA broadcasts led to the success of the radio industry. People began buying the first radios. Other companies decided radio could make a profit. Only four years after the first KDKA broadcast, there were six hundred radio stations in the United States. Radio stations also began to broadcast in other countries.

Radio stations began selling “air time” as a way to pay their workers and to pay for needed equipment. A few minutes of air time were sold to different companies so they could tell about their products to the radio station’s listeners. This method of supporting radio and later television is still used today.

SHIRLEY GRIFFITH: Radio changed the way people thought and lived. It permitted almost everyone to hear news about important events at the same time. Political candidates could be heard by millions of listeners. The same songs were heard across the country.

The work by British scientist James Maxwell and German scientist Heinrich Hertz led to the development of modern communications technology. This includes television broadcasts, satellite use, cellular telephones, radio-controlled toys and much more.

(MUSIC)

STEVE EMBER: Now we will explain electromagnetic waves. We will begin with Heinrich Hertz’s experiment. You can also try this experiment. First, move the controls on your radio to an area where no station is being received.

Now, you will need a common nine-volt battery and a metal piece of money. Hold the battery near the radio and hit the top of the battery with the coin. You should hear a clicking noise on the radio.

Your coin and battery are a very simple radio transmitter. This radio will not transmit very far. However, if you know a little of Morse code, you could communicate with this device.

SHIRLEY GRIFFITH: Electromagnetic energy travels almost like an ocean wave – up and down, up and down. It also travels at the speed of light – two hundred ninety-nine million seven hundred ninety-two thousand four hundred fifty-eight meters each second.

Scientists have learned how to separate radio waves into different lengths called frequencies. This permits many radio stations to broadcast at the same time and not interfere with each other.

STEVE EMBER: You may be hearing our broadcast on what is called short wave. These are frequencies between three thousand and thirty thousand kilohertz. They are often called megahertz. One megahertz is the same as one thousand kilohertz.

Short wave is good for broadcasting very long distances. The short wave signals bounce off the ionosphere that surrounds the Earth, back to the ground and then back to the ionosphere.

The first radio broadcasts were made using amplitude modulation. AM radio can be sent over larger distances, but the quality of the sound is not as good as a later kind of radio signal processing, called frequency modulation. FM radio stations transmit in a range of frequencies between eighty-eight and one hundred eight megahertz. AM radio is between five hundred thirty-five and seventeen hundred kilohertz.

SHIRLEY GRIFFITH: Radio technology continues to improve. Today, VOA broadcasts to satellites in space that send the signal back to stations on the ground that transmit programs with a clear signal.

Radio personality Howard Stern in New York City during his first show on Sirius Satellite Radio in 2006
AP
Radio personality Howard Stern in New York City during his first show on Sirius Satellite Radio in 2006

In the United States, people who want satellite radio programs can buy the services of the company Sirius XM. The company provides listeners with programs about music, news, sports, weather, politics and much more. Many of these programs do not include commercial advertising. People can use these satellite radio services in their cars, homes or on portable devices. More and more radio stations are also broadcasting using digital radio technology.

STEVE EMBER: The Internet is also adding to the expansion of radio programming. Radio stations around the world can put their programs on the Internet for listeners everywhere to hear. The website Pandora began its Music Genome Project to create a database of song descriptions. Pandora’s Internet radio is able to predict what songs listeners will like based on their earlier musical choices. Listeners can create their own personalized radio programming with this and other forms of Internet radio.

We think Heinrich Hertz would look at all these developments and be very proud of the device he made that he thought would never be of any use.

(MUSIC)

SHIRLEY GRIFFITH: This program was written by Paul Thompson. It was produced by Dana Demange. I’m Shirley Griffith.

STEVE EMBER: And I’m Steve Ember. Our programs are online with transcripts and MP3 files at voaspecialenglish.com. And you can find us on Twitter, Facebook and YouTube at VOA Learning English. Join us again next week for EXPLORATIONS in VOA Special English.


Tuesday, December 21, 2010

"Clara Barton" Founder of The Red Cross, from VOA




VOICE ONE:

I'm Ray Freeman.

VOICE TWO:

And I'm Shirley Griffith with the Special English program, People in America. Every week we tell about a person who was important in the history of the United States. Today we tell about a woman who spent her life caring for others, Clara Barton.

(MUSIC)

VOICE ONE:

Clara Barton was a small woman. Yet she made a big difference in many lives. Today her work continues to be important to thousands of people in trouble.

Clara Barton was an unusual woman for her time. She was born on Christmas day, December twenty-fifth, eighteen twenty-one. In those days, most women were expected to marry, have children and stay home to take care of them. Barton, however, became deeply involved in the world.

By the time of her death in nineteen twelve, she had begun a revolution that led to the right of women to do responsible work for society. As a nurse, she cared for thousands of Wounded soldiers. She began the American Red Cross. And, she successfully urged the American government to accept the Geneva Convention. That treaty established standards for conditions for soldiers injured or captured during wartime.

VOICE TWO:

Clara Barton really began her life of caring for the sick when she was only eleven years old. She lived with her family on a farm in the northeastern state of Massachusetts. One of her
brothers, David, was seriously injured while helping build a barn. For two years, Clara Barton took care of David until he was healed.

Most eleven-year-old girls would have found the job impossible. But Clara felt a great need to help. And she was very good at it. She also seemed to feel most safe when she was at home with her mother and father, or riding a horse on her family's land.

As a young child, Clara had great difficulty studying and making friends at school. Her four brothers and sisters were much older than she. Several of them were teachers. For most of Clara's early years, she was taught at home. She finished school at age fifteen. Then she went to work in her brother David's clothing factory. The factory soon burned, leaving her without a job.

VOICE ONE:

Clara Barton decided to teach school. In eighteen thirty-six, she passed the teacher's test and began teaching near her home in North Oxford, Massachusetts. She became an extremely popular and respected teacher.

After sixteen years of teaching, she realized she did not know all she wanted to know. She wanted more education. Very few universities accepted women in those days. So Clara went to a special school for girls in Massachusetts. While in that school, she became interested in public education.

VOICE TWO:

After she graduated, a friend suggested she try to establish the first public school in the state of New Jersey. Officials there seemed to think that education was only for children whose parents had enough money to pay for private schools.

The officials did not want Barton to start a school for poor people. But she offered to teach without pay for three months. She told the officials that they could decide after that if she
had been successful. They gave her an old building with poor equipment. And they gave her six very active little boys to teach.

At the end of five weeks, the school was too small for the number of children who wanted to attend. By the end of the year, the town built her a bigger, better school. They had to give her more space. She then had six hundred students in the school.

(MUSIC)

VOICE ONE:

Within a year, Clara Barton had lost her voice. She had to give up teaching. She moved to Washington, D.C. to begin a new job writing documents for the United States government.

Clara Barton started her life as a nurse during the early days of the Civil War in eighteen sixty-one. One day, she went to the train center in Washington to meet a group of soldiers from Massachusetts. Many of them had been her friends. She began taking care of their wounds.

Not long after, she left her office job. She became a full-time nurse for the wounded on their way from the fields of battle to the hospital.

Soon, Barton recognized that many more lives could be saved if the men had medical help immediately after they were hurt. Army rules would not permit anyone except male soldiers to be on the battlefield. But Barton took her plans for helping the wounded to a high army official. He approved her plans.

VOICE TWO:

Barton and a few other women worked in the battle areas around Washington. She heard about the second fierce battle at Bull Run in the nearby state of Virginia. She got into a railroad car and traveled there.

Bull Run must have been a fearful sight. Northern forces were losing a major battle there. Everywhere Barton looked lay wounded and dying men.

Day and night she worked to help the suffering. When the last soldier had been placed on a train, Barton finally left. She was just in time to escape the southern army. She escaped by riding a horse, a skill she gained as a young girl.

(MUSIC)

VOICE ONE:

For four years, Clara Barton was at the front lines of the bloodiest battles in the war between the North and the South. She was there at Antietam, Fredericksburg, and Charleston. She
was there at Spotsylvania, Petersburg, and Richmond. She cleaned the wounds of badly injured soldiers. She eased the pain of the dying. And she fed those who survived.

When she returned to Washington, Clara Barton found she was a hero. She had proved that women could work in terrible conditions. She made people understand that women could provide good medical care. She also showed that nursing was an honorable
profession.

After the war ended, Barton's doctor sent her to Europe to rest. Instead of resting, she met with representatives of the International Red Cross. The organization had been established
in eighteen sixty-three to offer better treatment for people wounded or captured during wars. She was told that the United States was the only major nation that refused to join.

VOICE TWO:

Barton began planning a campaign to create an American Red Cross. Before she could go home, though, the war between France and Prussia began in eighteen seventy.

Again, Clara Barton went to the fields of battle to nurse the wounded. After a while her eyes became infected. The woman of action was ordered to remain quiet for months in a dark room, or become blind.

When she returned to the United States she again suffered a serious sickness. She used the time in a hospital to write letters in support of an American Red Cross organization.

(MUSIC)

VOICE ONE:

In eighteen eighty-one, Barton's campaign proved successful. The United States Congress signed the World's Treaty of the International Red Cross. This established the American Chapter of the Red Cross. Clara Barton had reached one of her major goals in life.

The next year she successfully urged Congress to accept the Geneva Convention. This treaty set the international rules for treatment of soldiers wounded or captured in war.

For twenty-five years, Clara Barton continued as the president of the American Red Cross. Under her guidance, the organization helped people in all kinds of trouble. She directed the aid efforts for victims of floods in Johnstown, Pennsylvania and Galveston, Texas. She led Red Cross workers in Florida during an outbreak of the disease yellow fever. And she helped during periods when people were starving in Russia and Armenia.

VOICE TWO:

Clara Barton retired when she was in her middle eighties. For her last home, she chose a huge old building near Washington, D.C. The building had been used for keeping Red Cross equipment and then as her office. It was made with material saved from aid centers built after the flood in Johnstown.

In that house on the Potomac River, Clara Barton lived her remaining days. She died after a life of service to others in April, nineteen twelve, at age ninety.

She often said: "You must never so much as think if you like it or not, if it is bearable or not. You must never think of anything except the need --- and how to meet it."

(MUSIC)

VOICE ONE:

This Special English program was written by Jeri Watson. I'm Ray Freeman.

VOICE TWO:

And I'm Shirley Griffith. Join us again next week for another People in America program on the Voice of America.

Sunday, December 12, 2010

"Dust Echoes" Amazing Stories from Australia














Click on the link. You will see a number of circular icons above the picture. Put your cursor over the icons. The second one to the right is "Whirlpool". When you reach that page, click on "Original Story". First read the story, then watch the wonderful animated film. "Whirlpool" is about the conflict between two Australian Aboriginal Tribes, the Salt-Water People and the Fresh-Water People. You can also take a quiz after you watch the video, learn about the cultural background of the story, and the animators. Many thanks to Vukile Mgijima and Nik Peachey for this link.
Dust Echoes