question_answer

Name any two types of transmission systems that are commonly used for transmission of signals. Write the range of frequencies of signals for which these transmission systems are used.

Answer:

For the transmission of signals, following two types of transmission systems are used.

(i) Sky wave propagation or short wave propagation.

(ii) Space wave communication or line of sight communication.

Range of frequencies

(i) Sky wave propagation \[3\,\,\text{MHz}\,\,\text{}\,\,\text{f}\,\,\text{}\left| 30\,\,\text{MHz} \right.\]

(ii) Space wave communication

\[30\,\,\text{MHz}\,\,\text{}\,\,\text{f}\,\,\text{}\,\,300\,\,\text{MHz}\]