1. Name three ways that a higher-frequency signal called the carrier can be varied to transmit the intelligence. 2. Name two common household remote-c ontrol units, and state the type of media and frequency ranges used for each. 3. How is radio astronomy used to locate and map stars and other heavenly bodies? 4. In what segment of the communication i eld are you interested in working, and why? 5. Assume that all the electromagnetic spectrum from ELF through microwaves was fully occupied. Explain some ways that communication capability could be added. 6. What is the speed of light in feet per microsecond? In inches per nanosecond? In meters per second? 7. Make a general statement comparing the speed of light with the speed of sound. Give an example of how the principles mentioned might be demonstrated.
8. List i ve real-life communication applica tions not specii cally mentioned in this chapter. 9. “Invent” i ve new communication methods, wired or wireless, that you think would be practical. 10. Assume that you have a wireless application you would like to design, build, and sell as a commercial product. You have selected a target frequency in the UHF range. How would you decide what frequency to use, and how would you get permission to use it?