Chapter 13 Information & Communication Technology

Introduction to Television Technology

Antenna-powered television is an older technology that has been largely replaced by Internet TV and Dish TV. Before Dish TV, cable TV was very popular. Of these, antenna-connected TV offers the poorest audio-visual quality because the electromagnetic waves lose energy as they travel through the air from the transmitter to the user’s home. This results in a weaker potential difference (p.d.) on the antenna and a weaker electrical current, which acts as the modulated signal for the broadcast.

In modern televisions, the signal from the antenna is converted into digital signals by internal circuits. Cable TV also uses modulated signals that travel through a wire. A cable modem is needed to use a computer as a television with a cable connection. Dish TV broadcasts digital signals received from a satellite.

Analog to Digital Conversion

For broadcast, it is necessary to convert analog signals (like sound and light) into digital signals for transmission and then convert them back to analog signals for viewing and hearing. This is done using an Analog-to-Digital Converter (ADC) and a Digital-to-Analog Converter (DAC). The ease of transmitting digital signals has led to their extensive use in information and communication. This has given rise to the term “Digital Native” or “Digital Citizen” to describe people who are active on social media. It is important to maintain courtesy and positive behavior online. While online facilities have many benefits, improper use can negatively impact physical, mental, and emotional well-being.

Digital Signals

A digital signal is a signal that represents data as a sequence of discrete values.

A signal is a physical quantity that changes with time. A special device, like a transistor, is used in electronic devices to create digital signals. If the voltage were to increase and decrease continuously instead of switching between on and off, it would be an analog signal.

Digital signals are represented by only two digits, 0 and 1, in a binary system.

• With one binary digit, there are two possible combinations (0, 1).
• With two binary digits, there are four possible combinations (00, 01, 10, 11).
• With three binary digits, there are eight possible combinations.

This digital data is stored in a computer’s memory.

Computer Memory Units

• Bit (Binary Digit): The smallest unit of data, either 0 or 1.
• Byte: A group of 8 bits.
• Nibble: A group of 4 bits.
• Kilobyte (KB): 1024 Bytes
• Megabyte (MB): 1024 Kilobytes
• Gigabyte (GB): 1024 Megabytes
• Terabyte (TB): 1024 Gigabytes

Signal Transmission

Signal transmission is the process of sending a signal through a medium or channel. Sound is an analog signal. In landline phones, analog signals are sent through wires. In radio broadcasts, analog signals are also used. However, these analog transmissions can be affected by external factors like other waves and atmospheric conditions, making the signal unclear. To avoid distortion and ensure security, analog signals are often converted to digital signals. Digital systems allow data to be stored, transmitted, and recreated using combinations of 0s and 1s, with a very low probability of error.

Components of a Digital Communication System

1. Source: The origin of the signal (e.g., sound waves).
2. Input Transducer: Converts the source signal into an electrical signal (e.g., a microphone).
3. Encoder: Compresses the data into a minimum number of bits for efficient use of bandwidth.
4. Modulator: Modulates the data onto a carrier wave and converts the digital sequence into an analog signal for transmission.
5. Channel: The medium through which the analog signal travels to the receiver.
6. Demodulator: The first step at the receiver, where the received signal is demodulated.
7. Decoder: Re-digitizes the demodulated signal and corrects any potential errors.
8. Output Transducer: Converts the decoded electrical signal back into the original physical signal (e.g., a loudspeaker).
9. Output Signal: The final result of the transmission process.

Baseband and Broadband Transmission

Baseband Transmission

This is the transmission of digital signals through a channel without converting them into analog signals. Sending and receiving happen simultaneously in the same channel. It is used for short-distance transmissions, like connecting two computers with a cable.

Broadband Transmission

This is the transmission of digital signals after converting them into analog signals. This process requires modulation. Analog signals can be transmitted as optical or electromagnetic waves at various frequencies. The transmission medium is divided into two separate channels for sending and receiving, or two separate cables are used. This method is used for long-distance transmission. High-speed internet is an example of broadband transmission.

Advantages of Digital Transmission

• Less affected by deterioration and noise.
• The circuits used are more reliable.
• Digital circuits are cheaper and easier to design than analog circuits.
• Less possibility of signal overlap and cross-talk.
• The properties of digital signals do not change under normal conditions.
• Information security can be maintained through encoding and compression.
• Fewer errors during transmission due to the use of error-correcting codes.

Influence of Digital Technology on Information and Technology

The development of digital technology has improved the quality and accessibility of information and technology, leading to the modernization of telecommunications, the internet, digital media, and digital TV.

Digital Telecommunication

Digital communication has enabled faster communication. It also allows many telephone calls to be transmitted through a single channel or bandwidth.

Digital Media

These days, various mediums are available for information and communication. The electronic devices used for communication are known as digital media. Activities like creating new digital media, watching the news, and transmitting information online can be done via these electronic devices.

Digital TV

Digital TVs come in different shapes and have unique characteristics. High-definition TVs are made with the latest digital technology. Television services are delivered through various means:

• Terrestrial: Uses a transmitter for a particular terrestrial broadcaster.
• Mobile/Portable: Includes services like PDA + DMB and Car Audio + DMB.
• Satellite: Uses a satellite to transmit signals, for example, DirecTV in the USA.
• Cable: Transmits signals through a headend to homes, for example, Comcast.

Dish TV has expanded its television service to different parts of the country.

Digital Technologies Used in Daily Life

• Infrared and digital thermometer
• Calculator
• Online Newspaper
• Digital wallet
• Online library
• Speedometer
• Digital camera
• Smartwatch
• Calendar

Digital devices, which are products of the development of digital technology, have helped to make human activities very easy. As shown in the examples, digital technologies are applicable in various fields such as education, health, entertainment, and finance. Although the use of digital technology can make life easier, its misuse and reckless use can also create problems.

Positive and Negative Effects of Digital Technology on Daily Life

With the continuous development of digital technology, the number of users also increases. Some technologies can even change the lifestyle of the users. Some of the positive aspects of digital technology are as follows:

Positive Effects

(a) Digital Library: Digital versions of textbooks and other reading materials are available in a digital library. It helps develop book-reading habits in people. For example, various textbooks and different reference materials are kept in the CDC library.

(b) Online Newspapers: With the availability of the internet and smartphones, different online newspapers can be read. For example, www.gorkhapatraonline.com is an online portal.

(c) Digital Payment: Digital payment solves the problem of people having to carry a lot of money for shopping. Money can be sent to a seller’s bank account by scanning a QR code. Digital payments can also be used to pay taxes, book bus and plane tickets, etc.

(d) Online Business: Digital technology can be used to promote and sell business materials through the Internet.

(e) Social Networks: Social networks have given people the opportunity to express their opinions in public. They connect people digitally even if they are far away physically.

(f) Entertainment: With the development of digital technology, various games and music applications are available for people’s entertainment.

Negative Effects

Digital media has a direct impact on our lifestyle. Some of the negative effects of digital technology are as follows:

(a) Social Behavior Changes: People who spend an excessive amount of time online experience changes in their social behavior, i.e., the way they interact with others.

(b) Cybercrime: Crimes might be committed through social media and can affect people’s personal, family, and social lives. When a person’s reputation is damaged, it creates mental stress.

(c) Reduced Physical Consumption: Excessive use of digital material has reduced the consumption of physical material. This can result in the loss of business opportunities.

(d) Lack of Physical Exercise: A lack of physical exercise in children creates problems like obesity and weakness.

(e) Negative Impact of Digital Games: Digital games containing murder and violence can adversely affect the mental health and social well-being of an individual, as well as spread antisocial activities.

(f) Misuse of Digital Technology: The misuse of digital technology causes harm to other people through activities such as cybercrime.

The use of the Internet plays an important role in creating the positive and negative effects of digital technology mentioned above. Since internet users around the world spend a long time engaging in various common activities, the term ‘netizen‘ is used for such people.

Digital Citizenship

In the present age of the internet, all people of the world have the same rights to use the internet and to actively participate in it. So, everyone can be introduced as a citizen of the net. A person who actively uses and engages with the internet is known as a netizen. The word netizen refers to a citizen of the internet. A netizen is therefore a citizen of a globally connected internet. Likewise, digital citizenship is the citizenship of the netizen in the virtual world of the internet. The concept of digital citizenship helps to improve the overall internet world. The development of digital technology has made it possible to connect citizens from different places of the world through different types of communication channels such as telephone, internet phone calls, social network communication, etc. As a result, the concept of a global village has been developed.

Characteristics of a Good Netizen

The duties of a good netizen and internet etiquette are also connected with digital citizenship. The behavior displayed by netizens online should be socially acceptable. You should use polite and civilized language in online dialogues and communication through email, comments made public on social networks, etc. Online behavior should demonstrate personal respect and respect for others. Everyone should be treated with respect, even if they do not see each other personally. Anything posted online is permanent. Intellectual property on the internet is someone else’s product. Unauthorized use of such material is not permitted. If the material is to be used, the source must be cited.

Online Reputation

Reputation management is essential for netizens in the world of the internet, just as reputation is connected to people’s practical life. A person’s real name, photo, and other publicly available details should be used on their online profile. This shows the authenticity and reliability of the person’s profile. Likewise, all social media profiles should have the same username. The posts, comments, shares, etc., made by the same person in the real and virtual world on social networks show the person’s knowledge, expertise, etc. For online reputation management, a person should be careful about internet security. Poor privacy settings on social networks can lead to password theft and the possibility of posting content that harms the reputation of an individual.

Online reputation is not only personal but also associated with an organization. Information published on an organization’s website and statuses posted on its social media pages are official. The number of followers of that page indicates the credibility of that organization. Similarly, a presence on all major sites and social networks is required for institutional digital reputation. Online reputation can be managed by the timely resolution of comments and complaints made on institutionally opened websites and pages.

Digital Wellbeing

Staying online for a long time without maintaining the necessary physical balance can be harmful to health. It can cause problems like obesity, insomnia, vision problems, and mental stress. Likewise, unregulated internet use can cause problems such as depression, anxiety, dishonesty, low self-esteem, social isolation, loneliness, and aggressiveness.

Due to the existence of such problems, the concept of digital health is applied in our online life. The state of being healthy mentally, physically, socially, and emotionally by balancing the time spent on online and offline activities is called digital well-being. When using online technology, we should take care of our digital health and use it in such a way that it does not affect our overall health.

Cautions for Digital Wellbeing

Addiction to digital technology can make our lifestyle chaotic. Therefore, digital well-being skills are necessary to be aware of the possible effects of the unnecessary use of digital technology. Digital well-being can be achieved by cultivating habits such as separating screen time, setting time limits for social media use, and turning off mobile notifications at work. Awareness of digital well-being can be adopted by installing a digital well-being application on a smartphone. For example, applications such as Beta, Action Dash, Digital Detox, Microsoft Launcher, etc., can be used. Such applications help reduce the screen time of users.

Making Audio and Audio-Visual Materials

Audio content can be created by recording sound with the microphone of a computer or smartphone. Audio-visual content can also be created from camera recordings. A smartphone camera or a digital camera can be used for this.

In a recorded video file, a file extension is added to the name, such as .MP4. An MP4 file is a video file. Similarly, .3GP, .SVI, .MOV, etc., are also video file formats. If the audio-visual material recorded has unnecessary parts, the segment can be cut out from the video, or more than two video file clips can be combined to form a single video file. This kind of work comes under video editing.

Video Editing

A mobile application or software is needed to edit a video recorded by a camera. For example, video can be edited by using computer software like Adobe Premiere Pro and Filmora. Similarly, a video can also be edited by using the Windows video editing software included in the system software of a computer.

(a) Video Cutting

To cut a recorded video and prepare a short clip, follow these steps:

1. Launch the Video Editor by searching for it.
2. Click on “New video project” and type the project name (e.g., Class 10 ICT) and click OK.
3. Select the video from the computer memory and add it to the project library by dragging it to the editing panel.
4. For video cutting, select the video and click on “trim”.
5. To choose where the video is to be cut, play the video. Then separate the start time and end time using the two blue drag bars.
6. Finally, check the required clip length and click on “done”.
7. Select the cut clip in the editing panel and click “finish video”. Then click “export” in the window that appears.
8. In the end, choose a location on the computer to save the video clip.

(b) Video Joining

1. Copy the clips to be joined into a single folder on the computer.
2. Open a video editing software, select the required files from the computer memory, and add them to the project library.
3. Select these videos and drag them to the editing panel.
4. Select all the files to be joined in the editing panel and click on “finish video”.
5. Choose a location to save the final video file on the computer.

Editing can be done on both computers and smartphones. Smartphones have separate editing applications. To edit a video recorded from the camera, it can be opened from the mobile gallery. When you click on the video, an edit icon will appear. On clicking that icon, cut and crop options will be visible.

If there is no video editing application on the phone, the required application can be downloaded from the Play Store.

Just like editing a video using computer software, an audio file can also be edited. The file extensions of audio files are MP3, WAV, WMA, etc. If the software or application required for audio editing is not installed on the computer or smartphone, it can be downloaded and installed from the Windows Store, App Store, etc. For example, to edit an audio file, Audacity can be downloaded from www.audacityteam.org. Similarly, mp3 cutter software can be downloaded from any official source by using a Google search.

1. Choose the correct option for the following questions:

2. Differentiate between:

(a) Analogue Signals and Digital Signals

Basis of Difference	Analogue Signals	Digital Signals
Nature	They are continuous-time signals that vary smoothly over a range.	They are discrete-time signals represented by a sequence of binary values (0s and 1s).
Representation	Typically represented as continuous sine waves.	Typically represented as square waves or pulses.
Noise Immunity	More susceptible to noise and distortion during transmission, which degrades quality.	Less susceptible to noise. Error-checking and correction codes can be used to ensure data integrity.
Information Density	Carries less information for a given bandwidth.	Carries more information for a given bandwidth through compression and multiplexing.
Examples	Old landline telephones, medium wave radio, antenna-based television.	Computers, smartphones, Digital TV, CDs, DVDs.

(b) Analogue Signal Transmission and Digital Signal Transmission

Basis of Difference	Analogue Signal Transmission	Digital Signal Transmission
Signal Form	Transmits the signal in its original continuous waveform.	Transmits information as discrete binary pulses (0s and 1s).
Error Handling	Prone to noise and distortion, with no effective mechanism for error correction.	Highly robust against noise. Uses error-detection and correction codes to fix errors during transmission.
Security	Less secure, as the signal can be easily intercepted and understood.	More secure. The digital signal can be encrypted and compressed to protect the information.
Multiplexing	Less efficient. It is difficult to mix different types of signals.	Highly efficient. Multiple signals (voice, video, data) can be combined (multiplexed) and sent over a single channel.
Fidelity	Signal quality degrades over long distances as noise accumulates.	Signal quality can be perfectly maintained over long distances using repeaters that regenerate the signal.

(c) Digital well-being and Digital Reputation

Basis of Difference	Digital Well-being	Digital Reputation
Definition	The state of being healthy (mentally, physically, socially) by balancing online and offline activities.	The public perception of an individual or organization based on their online activity and digital footprint.
Primary Goal	To maintain personal health and prevent negative effects of technology overuse.	To build and maintain a positive and credible public image or brand online.
Focus	It is internally focused on an individual’s personal habits and relationship with technology.	It is externally focused on how others perceive you or your organization in the digital world.
Key Actions	Involves managing screen time, turning off notifications, and practicing mindfulness with technology.	Involves managing online profiles, posting thoughtful content, and interacting professionally with others.
Desired Outcome	A balanced, healthy, and productive lifestyle where technology is used as a tool, not a compulsion.	A trustworthy, credible, and influential online presence that can lead to personal or professional opportunities.

3. Answer the following questions:

(a) Define the bit and byte used in computer memory.

A bit (binary digit) is the smallest unit of data in a computer. It can have one of two values, either 0 or 1. A byte is a unit of digital information that consists of a group of 8 bits. It is the standard unit used to measure computer memory and storage capacity.

(b) Present the currently used high-speed internet as a Broadband transmission.

Broadband transmission refers to a high-speed, high-capacity method of transmitting data where a single medium (like a fiber-optic or coaxial cable) can carry multiple signals and types of traffic simultaneously. The high-speed internet we use today is a form of broadband because it allows for fast data transfer, enabling activities like streaming high-definition video, online gaming, and large file downloads, all of which require a large bandwidth that older dial-up (narrowband) connections could not provide.

(c) Write four advantages of digital transmission.

As stated in the textbook, four advantages of digital transmission are:

1. There is less influence of noise in the transmission channel.
2. There is less chance of distortion during amplification.
3. Information security can be maintained through encoding and compression.
4. There is less chance of error because codes for finding and correcting errors are used.

(d) Explain the impact of digital technology on the development of Information & Communication Technology with any two examples.

Digital technology has revolutionized information and communication. Two examples are:

1. Digital Telecommunication: It has enabled faster and clearer communication. Multiple telephone calls can be transmitted through a single channel or bandwidth, making the system highly efficient. It also allows for secure communication through encryption.
2. Digital TV: It has drastically improved the quality of television broadcasting, providing high-definition (HD) audio and visuals. Digital signals are less prone to interference, resulting in a clearer picture and sound compared to older analogue broadcasts.

(e) Present any four examples of digital technology used in daily life.

Based on the textbook, four examples of digital technology used in daily life are:

1. Digital Wallet: Allows for cashless payments by scanning QR codes or using mobile apps.
2. Online Library: Provides access to a vast collection of books and reference materials digitally.
3. Smartwatch: A wearable device that can track fitness, display notifications, and perform other computing tasks.
4. Digital Thermometer: Provides a quick and accurate reading of body temperature in a digital format.

(f) Write two positive and negative effects of digital technology in daily life.

Two Positive Effects:

1. Digital Payment: It has made financial transactions convenient and secure, removing the need to carry large amounts of cash.
2. Online Business: It allows businesses to promote and sell their products to a global audience through the internet, expanding their reach.

Two Negative Effects:

1. Mental and Social Impact: Excessive online time can lead to negative changes in social behavior, mental stress, and a feeling of isolation.
2. Cybercrime: The misuse of digital technology can lead to crimes like hacking, fraud, and cyberbullying, which can harm individuals’ personal and family lives.

(g) Define digital citizenship.

Digital citizenship is the citizenship of a netizen (an active user of the internet) in the virtual world of the internet. It refers to the responsible, ethical, and safe use of digital technology and participation in the online community.

(h) Write four characteristics of a good netizen.

Four characteristics of a good netizen are:

1. Respectful Communication: Using polite, civilized language in emails, comments, and online discussions.
2. Respect for Others: Treating everyone with respect online, even in disagreement, just as one would in person.
3. Understanding Permanence: Recognizing that anything posted online can be permanent and publicly accessible.
4. Respect for Intellectual Property: Not using someone else’s digital work (images, text, music) without permission and giving proper credit or citation when required.

(i) What is online reputation? Write with examples.

Online reputation is the public perception of an individual or organization based on their online activity and digital footprint. It is built from everything they post, share, and comment on, as well as what others post about them.

• Example for an individual: A person who consistently uses their real name and photo on their profiles and frequently posts insightful articles about their profession builds a positive and expert online reputation.
• Example for an organization: A company that actively posts updates on its social media pages and responds quickly and helpfully to customer complaints manages a positive online reputation for being credible and customer-focused.

(j) What is digital well-being?

Digital well-being is the state of being healthy mentally, physically, socially, and emotionally by creating a healthy balance between the time spent on online and offline activities. It involves using technology in a mindful way that supports one’s health and goals rather than detracting from them.

(k) Write the advantages of digital well-being.

The advantages of practicing digital well-being are the prevention of negative health effects associated with excessive technology use. This includes:

• Avoiding physical problems like obesity, insomnia, and vision strain.
• Preventing mental health issues such as depression, anxiety, and low self-esteem.
• Improving social connections in the real world and reducing feelings of isolation.
• Increasing focus and productivity by minimizing digital distractions.

(l) What four precautions are necessary for digital well-being?

Four precautions necessary for digital well-being are:

1. Separate Screen Time: Designate specific times for using devices and stick to them.
2. Set Time Limits: Use apps or device settings to limit the time spent on social media and other distracting applications.
3. Turn Off Notifications: Disable non-essential notifications to reduce interruptions and the urge to constantly check your phone.
4. Use Well-being Apps: Install applications designed to monitor and help reduce screen time.

(m) What is digital reputation management?

Digital reputation management is the continuous process of monitoring, influencing, and protecting the online perception of an individual or organization. It involves actively shaping one’s digital narrative through strategic posting and interaction while also addressing any negative or false information that appears online.

(n) Give two examples of digital reputation management.

1. For an Individual: An expert in a field regularly writing a blog or posting on social media about their area of expertise to establish themselves as a credible source.
2. For an Organization: A hotel monitoring review websites and social media, promptly responding to both positive and negative customer feedback to show they are engaged and care about customer satisfaction.

(o) Mention four importance of digital reputation management.

1. Builds Trust and Credibility: A positive online reputation makes an individual or organization appear more trustworthy and reliable.
2. Showcases Expertise: It allows individuals and organizations to demonstrate their knowledge and skills to a wide audience.
3. Protects Against Harm: It helps in mitigating the damage from false rumors, negative reviews, or malicious attacks.
4. Influences Opportunities: A strong online reputation can impact job prospects for individuals and attract customers and partners for businesses.

(p) Write two positive effects based on the use and utility of social media.

1. Freedom of Expression: Social networks provide a platform for people to express their opinions, share their creativity, and participate in public discourse.
2. Global Connectivity: They connect people digitally regardless of physical distance, helping maintain relationships with friends and family living far away.

(q) Write two possible negative effects of using social media.

1. Spread of Misinformation: False news and harmful content can spread rapidly on social media, misleading people and causing social harm.
2. Mental Health Issues: Constant comparison with others, cyberbullying, and addiction to social media can lead to anxiety, depression, and low self-esteem.

(r) Write your plan to make a 5-minute audio-visual material covering the topics included in any one unit under the science and technology of class 10. What can be done to make that audio-visual material of 3 minutes? Write, including, the necessary steps.

Here is a plan to create a 5-minute video on the unit “Information & Communication Technology” and then shorten it to 3 minutes, using the steps from the textbook.

Plan for a 5-Minute Video:

1. Scripting and Storyboarding:
   • Minute 0-1: Introduction to ICT. Define analogue vs. digital signals with simple graphics.
   • Minute 1-2: Explain the process of digital signal transmission, showing a simplified version of the textbook diagram.
   • Minute 2-3: Discuss the positive effects of digital tech (e.g., Digital Payment, Online Library).
   • Minute 3-4: Discuss the negative effects and introduce the concept of Digital Wellbeing.
   • Minute 4-5: Explain Digital Citizenship and the importance of Online Reputation.
2. Recording: Record short video clips or voice-overs for each segment using a smartphone or computer camera and microphone. Gather or create simple graphics for illustration.
3. Editing (Joining Clips):
   • Open a video editing software (like Windows Video Editor).
   • Start a “New video project”.
   • Add all the recorded video clips and graphics to the project library.
   • Drag the clips from the library to the editing panel (storyboard) in the correct sequence as per the storyboard.
   • Add background music or titles if needed.
   • Click “Finish video” and export the final 5-minute video file.

Steps to Shorten the Video to 3 Minutes: To make the audio-visual material 3 minutes long, I will use the video cutting/trimming function.

1. Identify Content to Cut: I will review the 5-minute video and identify parts that can be condensed. For example, I can shorten the explanations, remove less critical examples, or speed up certain sections. The goal is to remove 2 minutes of content.
2. Open the Project: Open the 5-minute video project in the video editor.
3. Use the Trim Tool:
   • Select the first clip in the editing panel that needs to be shortened.
   • Click on the “Trim” option.
   • Use the start and end drag bars to select only the most essential part of that clip, cutting out extra pauses or less important information. Click “Done”.
   • Repeat this trimming process for several clips throughout the video until the total runtime is reduced to approximately 3 minutes.
4. Final Export: Once the video is trimmed to the desired length, click “Finish video” again and export this new, shorter version as “ICT_3min_video.mp4”.