comm 2303.001 chapter 10

ENGINEERING

Chapter 10

The best way for a personto have happy thoughts isto count his blessings andnot his cash.

Anonymous

I. Pioneer Engineers A. Heinrich Hertz (radio waves theory) B. Guglielmo Marconi (radio waves proven) C. J. Ambrose Fleming (diode tube)

D. Lee de Forest (triode tube) E. Reginald Fessenden (voice transmission) F. Edwin Armstrong (FM transmission)

II. Radio Technology A. Electromagnetic Spectrum B. Broadcast Transmissions

III. AM/FM A. AM 1. Amplitude modulation 2. 535 to 1705 kilohertz (KHz) B. FM 1. Frequency modulation

2. 88.1 to 107.9 megahertz (MHz) 3. Subsidiary Communications Authorization (SCA)* a. known as subcarriers or sidebands*

b. Purposes* i. background music ii. weather reports iii. HD radio C. Signal Propagation 1. AM Radio uses Skywaves 2. FM Radio is “Line-of-Sight”

D. Skywave Interference 1. Stations’ Signals may not Overlap 2. Methods to Prevent Signal Overlap a. daytimers b. directional antenna c. reduce Power

E. Station Classifications 1. AM Classifications a. Class A b. Class B c. Class C d. Class D

2. FM Classifications a. Class C b. Class B c. Class A d. Class D e. Class L

IV. Satellite And Internet Radio A. Satellite Radio B. Internet Radio

V. Digital Audio Broadcasting (HD Radio)

VI. Smart Receivers (RBDS)

VII. Becoming An Engineer A. Basic Theory* 1. Sine wave a. cycles per second b. frequency c. amplitude

2. Reading meters a. current b. voltage c. resistance d. power B. Know Correct Meter Readings*

VIII. The Engineer’s Duties A. Proof of Performance B. Malfunctions Requiring Transmitter Shutdown* 1. Broadcasting beyond posted parameters 2. Broadcasting outside station license terms

C. Malfunctions Not Requiring Transmitter Shutdown* 1. Modulation monitor fails 2. Underpower 3. EAS monitor fails 4. Tower lighting failure

IX. Station Log A. Station Log B. Special Technical Records C. Retention of Logs

X. The Emergency Alert System (EAS) A. Origin B. National EAS* 1. Major or widespread emergency use 2. Presidential activation only C. Regional EAS*

XI. Automation

XII. Posting Licenses And Permits A. Station License must be Posted in a Conspicuous Location

B. Actions to Avoid by Announcer* 1. Willfully damaging radio apparatus or installations 2. Transmitting profane or obscene language 3. Knowingly transmitting false or deceptive messages

4. Knowingly transmitting an unassigned call letter 5. Willfully interfering with another radio signal 6. alcohol or drugs in the control room (unofficial)