2004 Dodge Caravan Owner's Manual - Page 160

160 UNDERSTANDING YOUR INSTRUMENT PANEL Clock Setting Procedure 1. Turn the ignition switch to the ON or ACC position and press the time button. Using the tip of a ballpoint pen or similar object, press either the hour (H) or minute (M) buttons on the radio. 2. Press the H button to set hours or the M button to set minutes. The time setting will increase each time you press a button. RADIO GENERAL INFORMATION Radio Broadcast Signals Your new radio will provide excellent reception under most operating conditions. Like any system, however, car radios have performance limitations, due to mobile operation and natural phenomena, which might lead you to believe your sound system is malfunctioning. To help you understand and save you concern about these "apparent" malfunctions, you must understand a point or two about the transmission and reception of radio signals. Two Types of Signals There are two basic types of radio signals...AM or Amplitude Modulation, in which the transmitted sound causes the amplitude, or height, of the radio waves to vary...and FM or Frequency Modulation, in which the frequency of the wave is varied to carry the sound. Electrical Disturbances Radio waves may pick up electrical disturbances during transmission. They mainly affect the wave amplitude, and thus remain a part of the AM reception. They interfere very little with the frequency variations that carry the FM signal.