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 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.
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.
The 1920's brought many advancements in technology which allowed Americans to entertain themselves at home; the radio was one of them. The radio was actually developed before the 1920's; however, it was banned during World War I and allowed to reappear after the Prohibition ended in 1919 (Events 72). After the Prohibition ended, and radio broadcasting was being brought back to life, many people started up their first stations, like Frank Conrad (Events 72). Frank Conrad's first broadcast consisted of the Presidential Election results (Events 72). As Conrad was one of the first people to broadcast, KDKA was one of the first radio stations to appear in the Unite...
Actually we use MP3 Players, iPods and other mobile devices to hear our music, some people still use cd players (For example: ME), In that time they have FM Radio, so they could be able to hear their music.
Radios in the book show power in many different forms, whether it be propaganda, the ability to know of the outside world or just owning a radio, sets one higher than those without.
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
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.
Siblings compete with one another to secure physical, emotional, and intellectual resources from parents. Depending on differences in birth order, gender, physical traits, and aspects of temperament, siblings create differing roles for themselves within the family system. These differing roles in turn lead to disparate ways of currying parental favor. (Epstein, 1997, p.51)
As suggested by Whiteman, this study is meant to provide insight into and possibly a better understanding of how conflict and relationships change (2011) and to show that rivalry or conflict can be an indicator of the nature of the relationship in later developmental periods. Finally, this research will tell the story of sisterhood through the shared experiences and connectedness of sisters across
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...
Sibling relationships has been an intriguing topic in developmental psychology for a long period of time. One of the interesting psychological phenomenon in this area of psychology is the environmental and genetic influences on sibling growth. These influences could be positive, such as the influence of success in their career; but some could be negative, such as the facilitation of alcohol use. In this comparative review essay, I will examine the similarities and differences between the popular press article Two Siblings, One Spotlight (Webber, 2011) and the peer-reviewed primary research article Genetic and Environmental Influences on Academic Achievement Trajectories During Adolescence (Johnson, McGue, & Iacono, 2014) that both address the
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.
"Short History of Radio A Short History of Radio With an Inside Focus on Mobile Radio." fcc.gov. Version 2003-2004. N.p., n.d. Web. 4 Dec. 2013. .
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...
Frequency modulation is, of course, used on the FM band. And it is used for