Works Cited

Brain, Marshall. "How the Radio Spectrum Works." HowStuffWorks. How Stuff Works, Inc., n.d. Web. 18 Feb. 2013. http://www.howstuffworks.com/radio-spectrum.htm 

Unknown. "AM, FM Waves." AM, FM Radio Waves and Sound. CyberCollege, 11 Apr. 2012. Web. 18 Feb. 2013. http://www.cybercollege.com/frtv/frtv017.htm

Unknown. "Parts of a Wave." Wave Parts. N.p., n.d. Web. 18 Feb. 2013.

http://zonalandeducation.com/mstm/physics/waves/partsOfAWave/waveParts.htm#crestAndTrough
 

Unknown. "Pitch and Frequency." Pitch and Frequency. The Physics Classroom, n.d. Web. 18 Feb. 2013. http://www.physicsclassroom.com/class/sound/u11l2a.cfm

Wkmn. "WKMN - A Newbie's Guide to Wireless Networks: How a Basic Radio Works." WKMN - A
Newbie's Guide to Wireless Networks: How a Basic Radio Works. Wkmn, 2002. Web. 14 Feb. 2013.

Y=aSin(bx)

• Starts at centerline which can also be known as the median (diagram above)
• then goes to maximum, back to center, minimum, center, repeat
• if the amplitude is negaitve, the wave will go to its minimum, to the center, then to the maxium, back to the center, repeat
• Period is equal to 2π
• If there is a b, you take the period divided by b: 2π/b  
• Keypoint Interval= 2π/4
• If there is a b, you will take that new period, 2π/b, and divide that by 4
• Amplitude=Distance from the centerline to the minimum or maximum
• vertical stretch/shrink
• The lead number of the equation (a)
• If the Amplitude is negative it is a vertical flip
• (Ex) y=-4*sinx
• Amplitude=4
• there's a negative 4, so the graph has a vertical flip

Y=aCos(bx)

• Period is equal to 2π
• Starts at maximum(diagram above)
• goes to its center, minimum, back to center, maximum, repeat
• Period=2π, if there is a b your period will be: 2π/b
• Keypoint Interval= 2π/4
• If there is a b, you will take that new period, 2π/b, and divide that by 4
• Amplitude=The lead number of the equation (a)
• Same rule with the amplitude applies to all of these functions

Example of Amplitude

      If a star is very bright, you know the amplitude is greater than a dimmer light because of how far the star's rays can reach. High amplitude=bright star, lower amplitude=dim star.

Frequency of a Wave

• The rate at which something occurs or is repeated over a particular period of time.
• Measured in Hertz (Hz)
• 1 Hz=1 vibration/second
• pitch corresponds with frequency
• high frequency=high pitch
• low frequency=low pitch
• highest pitched sound=20,000 Hz

How do Radios work?

1. First it all starts at any radio station.

2. Next the radio station sends out different kinds of waves called AM and FM signals.

3. Then it goes to a different converting to go the RF (AM and FM) frequency that is required to
use.

4. After that, those signals are sent to antenna transmitter that sends out these waves.

5. Then with the waves going to anything receiving these waves, like for example a radio.

6. Then the radio would have to be adjusted to be able to receive this certain RF signal to transmit
it.

7. Then the radio will transfer the waves back to an audio.

8. Finally it would transmit to any kind of news, hip hop, country, classical or any kind of music you
want to hear.

AM vs. FM

AM waves vs FM waves

FM Waves

FM stands for Frequency Modulation. This means that the frequency of the waves are varied. FM waves have higher frequencies than AM waves. For radios to catch these waves the antennas need to be higher because the waves are higher. These waves go in a straight line, so there can be some interference in them. These waves can also leave the Earth because they go in a straight line, and the Earth is round not square. FM radio has better quality. The stations, for example 93.7, are the frequencies. 93.7 means that there is an FM signal at a frequency of 93.7 MHz. Mega Hertz is millions of cycles per second.

AM Waves

AM stands for Amplitude Modulation which means that the amplitude, which is the highest or lowest point of the wave, is varied. The frequencies of these waves are much lower than FM waves. AM waves were discovered sooner than FM waves. This doesn't mean that the sound is greater, though, because it's not. AM waves are closer to the ground, unlike FM waves, so there are more interferences. AM radio doesn't have as great a quality as FM radio. AM radio goes by kilohertz. Kilohertz is thousands of cycles per second.