The Physics of an AM Radio Receiver
The AM Radio has been around for a long time. When the AM radio was first invented, it was not meant to be used to broadcast music. That is why today most music radio stations are on the FM band. Instead, the AM band was used to carry voice frequencies, thus, all the AM talk radio stations. Due to new technology, music is broadcast over the AM band but does not have the same sound quality as the FM band. According to the FCC regulations at www.fcc.gov, the AM broadcasters are only allowed 5 KHz each side of their carrier frequency for their side bands. These side bands will be explained in more detail later on. In order to understand an AM receiver, one must understand each stage and what it does. An AM receiver can be broken down into six stages. These stages will be explained one at a time.
The first stage is the RF amplifier. The AM antenna runs into the RF amp where the desired frequency is selected. As stated by Grob (1997), the typical band for AM is 535 Hz to 1605 KHz. For the duration of the paper, we will assume that we are trying to receive a station that is located on 1290 KHz signal. The antenna used must be able to pick up all the stations on the AM dial. Knowing this, we need to select the one we want to hear. In this case, we want 1290 KHz or The Country KOWW. When the dial on the radio is turned to select 1290 KHz, it does two things. There are two variable capacitors
The Physics of an AM Radio Receiver being adjusted. I will begin by discussing the first capacitor. This capacitor is connected in parallel with an inductor. While the capacitance changes as the dial is turned, the resonant frequency of the LC circuit also changes. This process is called inductor and capacitor in parallel. When the capacitor is in just the right spot, the resonant frequency will be 1290 KHz. This LC circuit is designed so that only the resonant frequency is passed. The 1290 KHz will now be passed on to the next stage and all other frequencies will be filtered out. The RF amp must also have good sensitivity, which according to Scott Rasmussen (2003), is the ability to amplify a very weak signal.
In the play when Oedipus asks Teiresias to reveal the murderer of King Laois, Teiresias blames Oedipus as the murderer and Oedipus denies the blame and gets angry on Teiresias. The chorus even denies the blame on Oedipus and takes Oedipus’ side. The chorus says the following lines to protect Oedipus “This is the king who solved the famous riddle, and towered up, most powerful of men. No mortal eyes but looked on him with envy, Yet in the end ruin swept over him”(Freud 988). Oedipus on the other hand who is really mad at Teiresias blames him and Creon for plotting against him. As Oedipus was blind from the start he was unaware of his origins which will cause him to trigger the unavoidable chain of events that would lead to the fulfilment of the prophecy. But he didn’t knew the fate itself was unavoidable. The irony of theme sight and blindness is produced here when Oedipus is compared to Teiresias. Oedipus who is not blind and has the capability to see with both of his eyes doesn’t finds anything wrong in killing a man, who he later discovers was King Laois and his group. He even took over the throne of Thebes and was found to be lying with his mother thinking her as his wife and having babies with her. On the other hand is Teiresias who is really blind and unable to see than...
Has anyone ever wondered how radio communications changed society during the 1930’s? According to the research done by the Education Foundation, many people believe that the most important development in the radio at that time was entertainment; this is entirely false. In fact, radio communications not only made an impact in the way people received their news, but also brought together a nation that got out of a brutal depression. Together, the nations as one made radio communications the commanding form of media in the 1930’s. As stations and businesses were beginning to establish themselves, companies from across the nation were taking notice in the department of advertisement. This new realm ignited a spark for the nation’s new economy which later boomed and gave rise to an economically and socially powerful country.
Sometimes in life people can be “blind” to the truth. The answer to their question or solution to their worry or problem may have been obvious yet, they could not “see” the answer. Therefore, they were blind to the truth. This blindness is not one in a physical sense but another kind of sight or vision. In Sophocles’ writing, Tiresias is a blind prophet that presents the truth to King Oedipus. Tiresias reveals that Oedipus has been blind to the truth his whole life and when he finally does find the truth, he loses his physical vision by saying, “so, you mock my blindness? Let me tell you this. You with your precious eyes, you’re blind to the corruption of your life.”(Sophocles) In this case, those who are blind ultimately do have a higher vision- the truth. The theme of sight versus blindness in Sophocles’ work
In the 1960’s news reports became mandatory to all radio programming. For most radio stations in the 60’s and even today when the news comes on, people usually change the station. The exception to the rule was CKLW. Their 20/20 news report would happen twenty minutes before the hour and twenty minutes after the hour. This was very different format; CKLW is credited for changing radio broadcasting of news forever with this particular format. When all other stations were reporting the news at the top of the hour, CKLW was still playing rock and roll music.
The radio grew in popularity and was as successful as it was because it was able to reach all across the nation, helped the American people interpret the Great Depression, and was a universal place of communication and entertainment. Although the first radio-wave theorem was developed in 1864 by James Clerk Maxwell, it was not until the 1920s and 1930s that the device really gained popularity in the U.S. During the Great Depression, families, advertisers, and even politicians used the radio for purposes such as entertainment, news, and a forum to the American people.1
Traditional AM/FM Radio. Sirius’s competition also includes traditional AM/FM radio. Unlike SIRIUS radio, traditional AM/FM radio has had a well established market for its services for many years and generally offers free broadcast reception paid for by commercial advertising rather than by a subscription fee. Also, many radio stations offer information programming of a local nature, such as local news and sports, which Sirius does not offer as effectively as local radio. Some radio stations also have begun reducing the number of commercials per hour, expanding the range of music played on the air and experimenting with new formats in order to compete more directly with satellite radio services.
After the First World War, many people were looking forward to good times. The 1920’s presented people with this time of fast-paced fun and adventure. Entertainment was the foremost part of everyday life during the 1920’s. Radio introduced a whole new practice of entertainment to people’s everyday lives. Likewise, through the utilization of the radio, people were able to experience a new medium to entertain themselves. Furthermore, the radio changed the face of society’s culture through its widespread use. In addition, radios provided people with a new, effective and efficient means of communication. Radio was a fundamental aspect in people’s lives during the 1920’s as it provided many people with news and entertainment in their day-to-day lives.
Their conclusion is that family dynamics have a key role in creating the context where sibling
The history of automobiles began in the early 1900s, at the times car radios wasn’t even a thought. “The earliest car stereos were receivers that used the battery voltage 6.3 volts at the time to run the filaments, and generated the required high voltage using a vibrator to drive a step up transformer.” “The receivers took more stages that the typical home receiver in order to ensure that enough gain was available to allow the AGC to mask signal fading when the car was driven around.” “Soon after that when the cars switched to 12 volt batteries, the same arrangement was used where instead of tubes 12 volt heaters were used (http://ezinearticles.com/?Origin,-Development-And-History-Of-The-Car-Stereo-System&id=924534).” The car stereo industry was founded in the 1920s. Even though the radio was created in the early 1900s, it didn’t come into widespread use until the 1920s. George Frost did the earliest car radio experiment in 192...
Oedipus’ fate caused him to isolate himself by blinding himself. Ironically, when Oedipus had his sight, he didn’t know the truth about the murder or even his life. He thought a group of bandits killed Laios and that his parents were from Corinth. Teiresias, a blind man, accused Oedipus of being blind “with both [his] eyes(p855, 196).'; Oedipus used his “blinded'; sight to discover the truth that brought him to his demise. Since he “had too long been blind to those for whom [he] was searching…from this hour [he would] go in darkness(p878, 49)!'; His strong reliance on his intellect unfortunately led him to see no more.
Ancient Greeks cared deeply about the pursuit of knowledge. Although the truth was often a terrifying concept, they still saw it as a critical virtue. One of the main underlying themes in Oedipus the King is the struggle of sight vs. blindness. Oedipus’ blindness is not just physical blindness, but intellectual blindness as well. Sophocles has broken blindness into two distinct components. The first component, Oedipus's ability to "see" (ignorance or lack thereof), is a physical characteristic. The second component is Oedipus's willingness to "see", his ability to accept and understand his fate. Throughout the play, Sophocles demonstrates to us how these components.
This "enlightening" starts with the revelations of a blind prophet named Tiresias. Though sightless, Tiresias can "see" the truth. He argues with Oedipus "...you have your sight, and do not see... . Yea, you are ignorant... ."(Sophocles, 15). Understandably, Oedipus is enraged at the prophet's accusations and fatally insists on investigating the murder of King Laius.
Analog communication employs continuous transmission of an electromagnetic wave form that varies in frequency and amplitude.
The radio was the first invention to allow mass communication to different parts of the world. It enabled information to be transferred thousands of miles. The development of the radio began in 1893 with Nikolai Tesla’s demonstration of wireless radio communication in St. Louis, Missouri. Nikolai Tesla’s work set the foundation for later scientists who worked to perfect the radio we now use in our daily lives. The man most associated with the invention of the radio is an Italian man named Guglielmo Marconi, who in 1986 was awarded the official patent for the radio by the British Government. The reason Marconi is most know for the invention of the radio is because he was the first to broadcast a transmission, which he did in 1899 and it was a mile long. Thanks to these great inventors and their brilliant minds we can now listen to sports nearly anywhere and everywhere we are in the world, due to the radio.
call sign, not just the radio frequency), an option to scan through channels searching only for stations playing a specified music genre, and of course adjustable treble and bass, which I'll never touch. The car manual, which had more pages dedicated to the stereo than the rest of the automobile, revealed a clever feature where I can program a volume for the radio to reset...