Frequencies?below approximately 10?MHz (wavelengths longer than 30 meters), including broadcasts in the?mediumwave?and?shortwave?bands (and to some extent?longwave), propagate most efficiently by skywave at night. Frequencies above 10?MHz (wavelengths shorter than 30 meters) typically propagate most efficiently during the day. Frequencies lower than 3?kHz have a wavelength longer than the distance between the Earth and the ionosphere. The?maximum usable frequency?for skywave propagation is strongly influenced by?sunspot?number.
143) Which of the following frequencies will be suitable for beyond-the horizon communication using sky waves?
Answer is:
10 MHz
Explanation:
Related Electronic Devices and Communication MCQ with Answers
Answer is:
Space waves
Explanation:
Frequencies in the UHF range normally propagate by means of spacewaves
Answer is:
(i), (ii) and (iii) but not (iv)
Explanation:
digital signals are only of form 0 or 1
Answer is:
No, 3258?km2
Explanation:
NO, it necessary for a transmitting antenna to be at the same height as that of the receiving antenna for line-of-sight communication
Answer is:
9V
Explanation:
m= M/A A is the carrier amplitude. Where, M is the modulation amplitude and is the peak change in the RF amplitude from its unmodulated value.