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Introduction
to Mass Communication MCM
101
VU
LESSON
32
TELEVISION
A NEW DIMENSION IN MASS
COMMUNICATION
Television
is the process of capturing photographic
images, converting them into
electrical
impulses,
and then transmitting the
signal to a decoding receiver.
Conventional transmission is by means
of
electromagnetic
radiation, using the methods of
radio.
Among
the technical developments that
have come to dominate our
lives, television is surely one of the
top
few.
In the developed world, the average household
watches television for seven
hours per day,
which
helps
to explain why news, sports,
and educational entities, as
well as advertisers, value the
device for
communication.
The
device we call the television is really an
image and sound receiver
that is the end point of a
broadcast
system
that starts with a television
camera or transmitter and requires a
complicated network of
transmitters
using
ground-based towers, cables,
and satellites to deliver the
original picture to our living
rooms.
TV
came like a bang as the time
distance between the invention of
radio and television is not
much. People
across
the world were still amazed
by the presence of radio in their
lives that within years they
were having a
device
which also showed images
with sound a great fun
indeed.
How
it started?
The
electronic way of communication was quite
well know by the start of the
20th century but in
almost
all cases it was limit to
sending or receiving voice messages.
Since most researchers and
scientists
were
focusing on the voice transmission, the
radio broadcast resulted
almost simultaneously in many
parts
of
the world with the exception of a difference of
few years. The name of
Marconi, however, stands
distinguished
in the eyes of many as the inventor of
radio.
The
inventor of television, the device
responsible for receiving voice as well
as images, is John Logie
Baird
of
Scotland. But obviously the
new invention has been the
result of the extensive work done by
scores of
other
scientists as well. The development of the television
occurred over a number of years, in
many
countries,
and using a wide application of
sciences, including electricity,
mechanical engineering,
electromagnetism,
sound technology, and electrochemistry.
No single person invented the
television;
instead,
it is a compilation of inventions
perfected by fierce
competition.
Early
Discoveries
Chemicals
that are conductors of electricity
were among the first
discoveries leading to the
TV.
Baron
Ȯns
Berzelius of Sweden isolated
selenium in 1817, and Louis
May of Great Britain
discovered, in
1873,
that the element is a strong
electrical conductor. Sir
William Crookes invented the
cathode ray tube in
1878,
but these discoveries took
many years to merge into the
common ground of television.
Paul
Nipkow of Germany made the first
crude television in 1884. His
mechanical system used a
scanning
disk
with small holes to pick up
image fragments and imprint
them on a light-sensitive selenium tube. A
receiver
reassembled the picture. In 1888, W.
Hallwachs applied photoelectric cells in
cameras; cathode rays
were
demonstrated as devices for
reassembling the image at the receiver by
Boris Rosing of Russia and
A.
A.
Campbell-Swinton of Great Britain, both
working independently in 1907. Countless
radio pioneers
including
Thomas Edison invented
methods of broadcasting television
signals.
Although
Logie Baird had been
developing his own methods
of televised images for many
years it was in
1924
that he first demonstrated a
mechanically scanned television system
which transmitted objects in
outline
and went on the following year to
show the head of a dummy, not just in
outline but as a real
image.
First
Pictures were shown on Sept
7, 1927.
TV
changes some basic
concepts
TV
is largely responsible for
bringing about so many social, cultural
and economic changes-
and
that
too with rapid speed,
and is considered as one major
factor to help globalize
human thinking and
understanding
on various matters by fully
exploiting all the elements
possible in visual communication,
or
say
broadcasting. More on this aspect
will be discussed in a coming
lecture.
107
Introduction
to Mass Communication MCM
101
VU
By
1935, mechanical systems for
transmitting black-and-white images were
replaced completely by
electronic
methods that could generate
hundreds of horizontal bands at 30
frames per second. Vladimir
K.
Zworykin,
a Russian immigrant who
first worked for
Westinghouse, patented an electronic
camera tube
based
on the cathode tube. Philo T. Farnsworth
and Allen B. Dumont, both
Americans, developed a pickup
tube
that became the home television
receiver by 1939.
From
Black and White to
color
The
Columbia Broadcasting System (CBS)
had entered the color TV
fray and battled with RCA
to
perfect
color television, initially with
mechanical methods until an
all-electronic color system could
be
developed.
Rival broadcasts appeared throughout
the 1940s although progress
was slowed by both
World
War
II and the Korean War. The
first CBS color broadcast on
June 25, 1951, featured Ed Sullivan
and
other
stars of the network.
Commercial
color television broadcasts were
underway in the United States by
1954.
In
December of 1954, RCA
introduced their 21" color
TV. Although the number recorded in
history
books
is 5,000 units sold, the common
belief (amongst collectors) is
that the actual number sold to
the
public
was considerably
less.
1950-1959
was an exciting time period for
television. In the USA, B&W television exploded
onto the scene
at
the beginning of the decade, mid-decade
saw electronic color television and
remote controls launched,
and
at the end of the decade the public
witnessed some interesting styling
changes and the introduction
of
transistorized
television.
II
World War
The
sudden outbreak of WW2 halted to some
extent progress on TV transmissions
and
improvement
in technological advancement in making TV a household item
for most. The B/W
limited
scale
TV transmission continued to excite
people. The images of war
ridden and ravaged sites on
mini
screens
of old-fashioned TV sets would pull crowd
to watch those and get
influenced by the devastation of
the
mad war. Seeing is believing, worked to
make people understand as who
was winning the war and
who
was
controlling the known cities at
different stages of the years
long fighting. It was a
sight not to be
forgotten
for those who first
witnessed defeat of German armies at
different fronts and
marching of the
allied
forces on the German land towards the
last days of the war.
TV
Programs
TV
program pattern remained like the ones
seen on radio broadcast.
Classification of its
transmission
has been made in the
following manner.
News
Music
Films
Comedy
shows
Live
shows
Sports
There
are currently 3 main
television transmission standards used
throughout the world:
NTSC
-
National Television Standards
Committee. The oldest existing
standard, developed in the USA.
First
used in 1954. Consists of
525 horizontal lines of
display and 60 vertical
lines.
SECAM
-
Systθme Ιlectronique pour Couleur
avec Mιmoire. Developed in
France. First used in 1967.
A
625-line
vertical, 50-line horizontal display.
PAL
-
Phase Alternating Line.
Developed by German engineer Walter Bruch
who patented his
invention
1963
and the first commercial
application of the PAL system
was in August 1967. Also a
625/50-line
display
and alternative of NTSC. Proponents call
it "Perfection
At
Last."
108
Introduction
to Mass Communication MCM
101
VU
Broadcast,
Cable, and Satellite Television
Transmission
Television
programs may be transmitted either "live"
or from a recording. The principle
means
of
recording
television programs for future
use is videotape recording. Videotape recording is
similar
to
conventional
tape recording .The sound is recorded
along with the video signal on the
same tape.
When
a television program is broadcast, the varying
electrical signals are then
amplified and used
to
modulate
a carrier wave the modulated carrier is
usually fed to an antenna,
where it is converted
to
electromagnetic
waves and broadcast over a
large region. The waves are
sensed by antennas
connected
to
television
receivers.
The
range of waves suitable for
radio and television transmission is
divided into channels, which
are
assigned
to broadcast companies or
services.
Most
television viewers across the world no
longer receive signals by using
antennas; instead, they
receive
programming
via cable television. Cable delivery of television
started as a way to improve reception.
A
single,
well-placed community antenna received
the broadcast signals and
distributed them over coaxial
or
fiber-optic
cables to areas that
otherwise would not be able
to receive them. Today,
cable television is
popular
because of the wide variety of programming it can
deliver. Many systems now
provide more than
100
channels of programming. Typically, a
cable television company receives
signals relayed from
a
communications
satellite and sends those
signals to its
subscribers.
The
first transatlantic television broadcast
was accomplished by such a
satellite, called Telstar, on
July 10,
1962.
Some television viewers use
small satellite dishes to
receive signals directly
from satellites. Most
satellite-delivered
signals are scrambled and
require a special decoder to receive them
clearly.
The
Future
The
future of television seems bright.
More research is going into
this process. High
Definition
Television
(HDTV) was developed by the Japanese
Broadcast Corporation and
first demonstrated in
1982.
This
system produces a movie-quality picture
by using a 1,125-line picture on a "letter-box"
format screen
with
a 16 to nine width to height
ratio. High-quality, flat
screens suitable for HDTV,
are being perfected
using
synthetic diamond film to emit electrons
in the first application of synthetic
diamonds in electronic
components.
Other
developments in the receiver include gold-plated
jacks, an internal polarity
switch on large
screens
that
compensates for the effect of Earth's
magnetic field on image reception,
accessories to eliminate ghosts
on
the screen. Liquid crystal
display (LCD) technology is also
advancing rapidly as an alternative to
the
cumbersome
television screen. Assorted computer
chips add functions like
channel labeling, time and
data
displays,
swap and freeze motions,
parental channel control,
touch screens, and a range
of channel-surfing
options.
Digital
television of the future will allow the
viewer to manipulate the angle of the camera,
communicate
with
the sports commentator, and merge
and edit movies on screen.
Two-way TV will also be
possible.
Current
screens may be used thanks
to converter boxes that change the
analog signal that
presently
energizes
the phosphors on the back of your
television screen to digital signals
that are subject to
less
distortion--and
are the language of computers. Computer
technology will then allow a
world of
manipulation
of the data as well as broadcast of
six times as much
data.
109
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