Objectives
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To be able to understand how radio was invented and by who
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To gain an understanding of how radio has developed over
the centuries and the difference between 20th century radio
and 21st century radio
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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 1864.
• German physicist Heinrich Hertz confirmed the theory in a
laboratory in 1888.
• 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
• http://www.youtube.com/watch?v=
HxUPXUijuT4
Radio Stations - 1922
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
1940
http://www.youtube.com/watch?v=OWjjxnITG8I&feature=related
1960
http://www.youtube.com/watch?v=Ts5EfWPy-ew
1970
https://www.youtube.com/watch?v=CKvd-2eKg3A
1980
https://www.youtube.com/watch?v=LXvSfv5jhHU
2000
http://www.youtube.com/watch?v=vcWdxKF8N2I&feature=related
Radio stations- 2006
Events in Radio History
There are many major events that have occurred in
the 20th century radio history.
One good example of a major event in the 20th
century that was broadcasted on radio:
• Martin Luther King
http://www.youtube.com/watch?v=cefI3Fw51bA
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
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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