WorksheetsDIGITAL TV ENGG
Total questions: 30
Worksheet time: 15mins
In the visible spectrum of electromagnetic waves, the following has longest wavelength
green
red
blue
white
First TV station in India was established in
1956
1959
1962
1965
A television system having N = 525 and P = 25 frames/s has a horizontal sync frequency of
15,625
625
525
50
In T.V., the picture signal is
amplitude modulated and at the low-frequency end of each channel allocation
frequency modulated and at the low-frequency end of each channel allocation
amplitude modulated and at the high frequency end of each channel allocation
None of the above
In order to eliminate ghosts in TV picture, one important method is to
cannect a booster
change the antenna orientation or location
use a multiband antenna
transmission line
T.V. broadcasting in India is done in
U.H.F. band
microwave band
V.H.F. band
None of above
TV transmitters of satellites use
image orthicon
vidicon
CRT
photoelectric cell
One of the advantages of using aluminium screens in modern picture tubes is to
provide brighter pictures
protect internal aquadag coating
protect the flourescent material
increase persistence of vision
Ghost images are produced on the screen of a TV receiver when
brightness control is misadjusted
contrast control is under-adjusted
centring magngent is misadjusted
both direct and reflected signals are received
In fringe areas, a suitable receiving antenna would be a
simple dipole
turnstile
high-gain V-antenna
high-gain Yagi antenna with rotor
For satisfactory reception in farfringe areas, it is often necessary to use
a CATV system
a MATV system
interference filters
an all-channel antenna
To be most effective, a booster amplifier should be installed
at the antenna end of the lead-in
at the receiver end of the lead-in
half-way between the antenna and the receiver
between the receiver and contrast control
A TV signal from the antenna is processed by
local oscillator
RF amplifier
transmission line
RF tuner
In a TV receiver, IF channel bandwidth is approxiniately
50 kHz
45.75 MHz
3.5 MHz
4.5 MHz
Basically, a picture detector is
an IF-video coupler
power rectifier
demodulator
ratio detector
The picture tube employed by a colour TV receiver is
one-colour
two-colour
three-colour
B & Wand three-colours
Additive primary colours are
red, white, blue
red, yellow, blue
blue, red and green
R?Y, B?Y and G?Y
Additive complementary colour are
yellow, red and blue
yellow, cyan and magneta
R?Y, B?Y and G?Y
orange, violet and yellow
The saturation of a colour is decreased when it is blended with
black light
itself
white light
red, yellow or blue light
Y-signals are also called -- signals.
colour-difference
chroma
luminance
multiplexed
White is
abundance of light
one of the complementary colours
a brightness characteristic of light
one of the primary colours
The red, green and blue chroma amplifiers drive the
chroma bandpass amplifiers
video amplifier
chroma demodulators
colour picture tube
Poor convergence produces images which have
random interference
colour fringing
unstable sync lock
aroma phase shift
The colour subcarrier is suppressed at the transmitter in order to
avoid cochannel interference
minimize interference between chroma signal and Y?signal
minimize adjacent channel interference
save energy
A degaussing coil is used for
demagnetising transformer cores
demagnetising colour picture tubes
rotating directional antennas
trap inductors
Magneta is the complement of
green
red
blue
yellow
The shadow mask in colour TV picture tube is used to
ensure that each beam hits its own target
decrease piture contrast
reduce X-ray emission
increase screen brightness
In TV production, `talkback' means
open microphone used for cueing and briefing instructions
headphones worn by camera and sound staff
a machine for producing TV pictures , from motion pictures
transmitter linking director with floor manager
One sign of week TV aerial signal is
presence of ghost images
fading of the picture
snow in the picture
feeble brightness of the screen
In TV if there is no brightness but sound is normal, the trouble could be in
horizontal oscillator
vertical oscillator
R.F. amplifier
none
