| 1. | Modulation is primarily accomplished to ? | |
|
Produce side bands
|
||
|
Mix two-waves of different frequencies
|
||
|
Improve transmission efficiency
|
||
|
Transmit audio-frequency signal over long distance
|
||
View Answer
Discuss in Forum
Report Question| 2. | If modulation index is 0.8 then what will be the transmission power efficiency for a tone modulated signal ? | |
|
24.24%
|
||
|
11.11%
|
||
|
33.33%
|
||
|
21.95%
|
||
| 3. | Percentage modulation of an AM wave having a power content of 8 KW at carrier frequency and 2 KW in each of its side bands is: ? | |
|
60%
|
||
|
70%
|
||
|
100%
|
||
|
80%
|
||
| 4. | A 1 kW carrier is Amplitude Modulated to a depth of 60%. The total power in the modulated carrier is ? | |
|
1 kW
|
||
|
1.06 kW
|
||
|
1.6 kW
|
||
|
1.18 kW
|
||
| 5. | A carrier is modulated by two modulating waves A and B having modulation index of 0.6 and 0.8 respectively. The overall modulation index is ? | |
|
1.0
|
||
|
0.7
|
||
|
0.2
|
||
|
1.4
|
||
| 6. | An AM signal with a carrier of 6KW produces a modulation of 100% what will be the power produced in each side band ? | |
|
1KW
|
||
|
0.15KW
|
||
|
15KW
|
||
|
1.5KW
|
||
| 7. | The modulation index of an amplitude modulated wave is changed from 0 to 1. The transmitted power is ? | |
|
Doubled
|
||
|
Halved
|
||
|
Increased by 50 percent
|
||
|
unchanged
|
||
| 8. | In amplitude modulated system if the total power is 600W and the power in the carrier is 400W, the modulation index ? | |
|
0.5
|
||
|
0.75
|
||
|
0.9
|
||
|
1
|
||
| 9. | The ratio of modulating power to total power at 100% modulation will be ? | |
|
2:3
|
||
|
3:1
|
||
|
1:3
|
||
|
3:2
|
||
| 10. | Before transmission message signal is modulated with carrier signal for : ? | |
|
Decreasing the height of transmitting antenna
|
||
|
Increasing the amplitude of message signal
|
||
|
Decreasing the amplitude of message signal
|
||
|
Increasing the height of transmitting antenna
|
||