2. Unit 5: Evolution of Technology in Science
Topic: Amplitude Modulation: AM, and Frequency Modulation: FM
Learning Target: I can…
Explain why FM frequencies often sound better than AM frequencies on the radio
Standard(s):
MS-PS4-1. Develop a model and use mathematical representations to describe waves that include frequency, wavelength, and how the amplitude of a wave is related to the energy in a wave.

3. Homework Write 1-3 paragraphs to compare and contrast the reflection, refraction and diffraction of waves Problem of the Day What do you think causes your cell phone to not receive a signal?

4. Discussion Questions
Have you ever listened to AM radio?
Have you ever listened to FM radio?
Why one sounds better? Why?

5. Amplitude
The amplitude of a wave is half the distance between a crest and a trough on a wave.

6. Amplitude
The vibrations that produce a wave transfer energy to the wave. The more energy the wave carries the greater its amplitude. The diagram below is used to represent a wave (sound) with different amplitudes.

7. AM & FM
The 2 most popular types of electronic wave signals are AM (amplitude modulation) and FM (frequency modulation). Modulation is the process of transforming an electronic wave signal into an electromagnetic wave to transport that signal.

8. AM
In amplitude modulation AM you vary the amplitude of the wave.

9. FM
In frequency modulation FM you vary the frequency of the wave.

10. Lab Activity
We are now going to perform an experiment/activity in which you will observe an AM wave signal and an FM wave signal and compare and contrast their characteristics. We will use equipment from our COSMOS Technology Toolkit: a computer and monitor, an ADALM-PLUTO Transceiver and antenna. The materials are already assembled on your desks. Get ready and wait for your teacher to tell you to begin