Radio: Telecommunication Engineering Test! Trivia Questions Quiz

A transducer is a device that converts a non-electric signal, such as sound or light, into an electrical signal. It is commonly used in various applications, such as microphones, speakers, and sensors. By converting the non-electric signal into an electrical signal, the transducer allows for further processing, transmission, or storage of the information. Therefore, a transducer is the correct answer for converting a non-electric signal into an electrical signal.

The frequency range of 1GHz to 30GHz is referred to as micro waves. This is because micro waves have frequencies within this range. Sound waves have much lower frequencies, typically below 20kHz, and are not within the given range. Mini waves is not a recognized term for any specific frequency range. Therefore, the correct answer is micro waves.

The carrier in optical communication refers to the electromagnetic waves that carry the information. Optical frequency refers to the frequency range of light waves, which is typically in the range of hundreds of terahertz. Therefore, the correct answer is "electromagnetic waves in optical frequency."

Messages travel from a transmitter to a receiver with the help of a channel. The channel is the medium through which the messages are transmitted, allowing the communication to occur. The channel can be a physical medium, such as wires or cables, or it can be a wireless medium, such as airwaves or radio frequencies. Regardless of the specific type of channel used, it serves as the pathway for the messages to travel from the transmitter to the receiver.

In AM (Amplitude Modulation), the modulation index represents the extent to which the carrier signal is varied in amplitude. When the modulation index is 1, it means that the amplitude of the carrier signal is varied to its maximum extent. This results in the maximum power being transmitted in the AM signal. Therefore, when the modulation index is 1, the maximum power in AM is achieved.

An earth station receiver consists of an RF to IF down converter. This component is responsible for converting the high-frequency radio signals received from the satellite into intermediate frequency signals. The RF to IF down converter is essential in the receiver as it allows for further processing and demodulation of the signals before they are converted back to their original form. The IF to RF converter is not necessary in this scenario, and the options of either (a) and (b) or none of these are not applicable as only the RF to IF down converter is required.

The FM signal has a larger bandwidth compared to the AM signal. This means that the FM signal can carry more information or data within a given frequency range. The larger bandwidth allows for a higher quality of audio transmission and the ability to transmit additional data such as RDS (Radio Data System) information.

A PIN photo diode is a type of optical detector that consists of three layers: P-type, Intrinsic, and N-type. It is designed to convert light signals into electrical signals. The P and N layers create a depletion region in the Intrinsic layer, which helps in the absorption of photons. When light strikes the PIN photo diode, it generates electron-hole pairs, which can be detected as a current. This makes the PIN photo diode an ideal choice for applications such as optical communication, remote sensing, and photovoltaic devices.

When the modulation index increases in AM modulation, the transmitted power is increased. This is because the modulation index represents the extent of variation in the carrier signal due to the modulation. As the modulation index increases, the amplitude of the carrier signal is modulated more significantly, resulting in a stronger and more powerful transmitted signal. Therefore, the correct answer is increased.

Modulating the signal is the correct answer because modulation is a process that allows the signal to be transmitted over long distances without interference. Modulation involves varying the characteristics of the signal, such as its amplitude, frequency, or phase, to encode the information. This allows the signal to be easily distinguished from other signals and reduces the chances of interference from noise or other sources. Amplifying the signal may increase its strength but does not necessarily reduce interference. Multiplying and demodulating the signal are not effective methods for reducing interference.

Video signals in TV are amplitude modulated. This means that the amplitude of the signal is varied in order to carry the video information. Amplitude modulation is commonly used for transmitting audio and video signals because it is able to preserve the original signal quality and is less susceptible to noise and interference.

The correct answer is IF to RF converter because an earth station transmitter is responsible for transmitting signals from the earth to satellites. The RF to IF down converter is used to convert the high frequency RF signals to intermediate frequency (IF) signals, while the IF to RF converter is used to convert the IF signals back to RF signals for transmission. Therefore, the IF to RF converter is an essential component of an earth station transmitter.

When the modulation index increases in FM modulation, the transmitted power remains constant. This is because the modulation index represents the extent of frequency deviation from the carrier frequency, and it does not affect the power of the transmitted signal. The power of the FM signal is determined by the amplitude of the carrier signal, which remains unchanged regardless of the modulation index. Therefore, the transmitted power remains constant.

AFC stands for Automatic Frequency Control. It is a feature commonly found in electronic devices that helps maintain the stability and accuracy of the frequency of a signal. AFC adjusts the frequency of a signal to compensate for any variations or drifts that may occur due to factors like temperature changes or component aging. This ensures that the signal remains within the desired frequency range, improving the overall performance and reliability of the device.

Super heterodyning is a technique used in radio receivers to convert high-frequency radio signals into a lower, more manageable intermediate frequency. This allows for easier amplification and filtering of the signal before it is demodulated to extract the original audio or video information. Therefore, the correct answer is radio receiver.