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प्रश्न
Would sky waves be suitable for transmission of TV signals of 60 MHz frequency?
उत्तर
No, signals of frequency greater than 30 MHz will not be reflected by the ionosphere but will penetrate through the ionosphere.
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संबंधित प्रश्न
Which of the following frequencies will be suitable for beyond-the-horizon communication using sky waves?
(a) 10 kHz
(b) 10 MHz
(c) 1 GHz
(d) 1000 GHz
Frequencies in the UHF range normally propagate by means of:
(a) Ground waves.
(b) Sky waves.
(c) Surface waves.
(d) Space waves.
Digital signals
(i) Do not provide a continuous set of values,
(ii) Represent values as discrete steps,
(iii) Can utilize binary system, and
(iv) Can utilize decimal as well as binary systems.
Which of the above statements are true?
(a) (i) and (ii) only
(b) (ii) and (iii) only
(c) (i), (ii) and (iii) but not (iv)
(d) All of (i), (ii), (iii) and (iv).
Whatis the difference between analogue signal and. digital signal?
Distinguish between ‘Analog and Digital signals’.
Write any two factors which justify the need for modulating a signal ?
Draw a diagram showing an amplitude modulated wave by superposing a modulating signal over a sinusoidal carrier wave.
Write briefly any two factors which demonstrate the need for modulating a signal. Draw a suitable diagram to show amplitude modulation using a sinusoidal signal as the modulating signal.
What do you mean by bandwidth of a signal? Give its importance.
Broadcasting antennas are generally