Communication Systems
If fm is the modulation frequency in FM, the modulation index
If fm is the modulation frequency in FM, the modulation index is proportional to
- fm
- 1/fm2
- fm2
- 1/fm
What should be the minimum length of the antenna capable
What should be the minimum length of the antenna capable of emitting audio signal of wavelength λ?
- λ
- λ/2
- λ/4
- λ/8
If the band width is 1.6 x 10^12 Hz, how many communication
If the band width is 1.6 x 1012 Hz, how many communication channels can be obtained with 16 KHz band width radio signal?
- 108
- 1011
- 1010
- 1015
An insulator used in a transmission line has dielectric constant
An insulator used in a transmission line has dielectric constant equal to 0.25. What is the velocity factor of the transmission line?
- 2
- 4
- 4/3
- 3/4
A T.V. tower has a height 200 m
A T.V. tower has a height 200 m. By how much the height of tower be increased to triple its coverage range?
- 1800 m
- 1600 m
- 800 m
- 600 m
A radar has a power of 1 Kw and is operating at a frequency of 10 GHz
A radar has a power of 1 Kw and is operating at a frequency of 10 GHz. It is located on a mountain top of height 500 m. The maximum distance upto which it can detect object located on the surface of the earth (Radius of earth = 6.4 x 106 m) is
- 80 km
- 64 km
- 40 km
- 16 km