Objectives To be able to understand how radio was invented and by who To gain an understanding of how radio has developed over the centuries and the difference between 20 th century radio and 21 st century radio To be able to understand the difference between AM and FM radio

A History Of Audio and Radio Radio is arguably the oldest electronic media. Yet despite the arrival of new technologies, radio still plays a major role in our lives. Each week, 90% of the population tunes into radio for at least five minutes. The average UK radio listener tunes into 22.9 hours of radio a week… But how did we get to this point?

How it all began… The theory of electromagnetic waves was first developed by Scottish physicist James Clerk Maxwell in German physicist Heinrich Hertz confirmed the theory in a laboratory in Italian inventor Guglielmo Marconi achieved the first practical demonstration of radio in 1901 by receiving a signal in Newfoundland, Canada, transmitted from Cornwall, England

Guglielmo Marconi Known as the ‘father of long distance radio transmission’ Inventor of radio in 1909 Radio Broadcasting in the UK began in 1920 with Marconi's experimental station 2MT located in Writtle, Essex HxUPXUijuT4 HxUPXUijuT4

Radio Stations

Task In Groups of 3 using the computer, research and discuss the following years and find a piece of radio broadcast from that time

Some Examples

Radio stations- 2006

Events in Radio History There are many major events that have occurred in the 20 th century radio history. One good example of a major event in the 20 th century that was broadcasted on radio: Martin Luther King

AM and FM Radio Amplitude Modulation Frequency Modulation The names describe how the radio waves that carry the signals are differentiated from each other. AM varies the length of the waves and FM varies how quickly they pulse. This is why the stations are designated by Hertz and Megahertz. Those units are used to measure wavelength and frequency.

AM AM stands for amplitude modulation AM radio ranges from 535 to 1705kHz The ground wave of AM radio doesn't go very far. This means numerous stations can be put on the same frequency without interfering with each other — assuming they are far enough apart.

FM FM stands for frequency modulated The FM radio band goes from 88 to 108 MHz To keep from interfering with each other FM stations must be 200KHz apart within the same geographic area. However, since the signals of FM stations cover only limited distances, the same frequencies can be used in different geographic areas of the country.

Task Individually listen to a radio show for 20 mins, any radio station of your choice this could be – Internet Radio – Community Radio – Public Service Broadcasting – Commercial You are to now make notes of what you can hear within the show The structure of the 20 min show you have listened to Tone of voices used Audience it is aimed at You will present this to the rest of your group