Extra Class - Audio Theory Course Author:Gordon West This audio theory course is a "book on tape" recorded by Gordon West. Listen to the sounds of ham radio as Gordon teaches you the material you need to know to pass your FCC Element 4 exam for your top-level Extra Class amateur radio license. Valid for exams from July 1, 2002 through June 30, 2006. A great way to study if you spend a lot of ti... more »me in your car or truck -- and a great study aid to Gordon's Extra Class book, 0945053266.« less