Matakuliah
Tahun
: G0462/English for Broadcasting
: 2005/2006
Audio and Video Technology
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Basic Principles
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Facsimile Technology
Transduction
Signal and Noise
Analog and Digital Signals
Oscillation and the Waveform
Frequency and Amplitude
Frequency Response
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Transduction
Transduction involves changing energy
from one form to another in audio and
video technology.
3
Signal Generation
Signal generation involves getting the grooves
onto a record, the vibrations into a microphone,
the blips onto a strip of audiotape, or the bits and
bytes onto a CD or floppy disk.
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Steps in Signal Processing
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5.
Signal generation
Amplification and processing
Transmission
Reception
Storage and retrieval
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Signal Generation
• Audio Signal Generation
• Video Signal Generation
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Amplification and Processing
Audio and video signals are amplified and
mixed by using audio consoles and video
switchers.
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Radio Transmission
• AM stations:
radio channels are classified into clear, regional,
and local channels.
• FM stations:
radio channels are classified according to power
and antenna height.
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TV Transmission
The traditional systems:
1. Over-the-air broadcasting utilizing
electromagnetic radiation on channels
located in the VHF and UHF portions of the
spectrum.
2. By wire through a cable system using coaxial
cable that can carry more than 100 channels
of programming.
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Signal Reception
• Radio receivers pull in AM, FM, and other
signals, in monaural or stereo.
• New digital multiband receivers are
becoming more prevalent.
• In TV, large-and small-screen receivers
have attained record sales in recent years,
abetted by new digital capabilities and
smart remote control devices.
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Web-casting Audio and video streaming
Streaming:
A technique that’s blurring the lines
between computers, TV sets, and radio
receivers.
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Storage and retrieval
• New technology is reshaping audio and video storage and retrieval.
• Phonograph records, compact discs, and videotapes are being
supplemented and may ultimately be replaced by digital storage
media, such as recordable CDs, digital versatile discs (DVDs, and
high capacity disk drives on computers.
• New phenomenon, audio and video streaming, permits radio and TV
stations to send their complex signals onto the internet.
• Today, any home computer with a soundcard, a CD-ROM drive, and
a microphone can produce and distribute its own radio and TV
programs.
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