Which mode of propagation is used by short wave broadcast services having frequency range from a few MHz upto 30 MHz ? Explain diagrammatically how long distance communication can be achieved by this mode. Why is there an upper limit to frequency of waves used in this mode?

Which mode of propagation is used by short wave broadcast services hav

1.	Which mode of propagation is used by short wave broadcast services having frequency range from a few MHz upto 30 MHz ? Explain diagrammatically how long distance communication can be achieved by this mode. Why is there an upper limit to frequency of waves used in this mode?
Answer» Solution :Sky WAVE propagation / Ionospheric reflection. ELECTROMAGNETIC waves of these frequencies are REFLECTED, by the ionosphere towards the earth. Electromagnetic waves of frequencies higher than 30 MHz PENETRATE the ionosphere and escape.

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Which mode of propagation is used by short wave broadcast services having frequency range from a few MHz upto 30 MHz ? Explain diagrammatically how long distance communication can be achieved by this mode. Why is there an upper limit to frequency of waves used in this mode?

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