Briefly discuss the functions of NAT, ICS, and WINS as well as their Essay

Briefly discuss the functions of NAT, ICS, and WINS as well as their uses - Essay Example It does the access control to resources between computers on the either sides of the firewall. NAT also conserves the number of public addresses used within an organization, considering the economic and security aspects Windows Internet Name Service (WINS) is the Microsoft’s NetBIOS name resolution service for the TCP/IP networks. WINS helps the users to access the resources with NetBIOS names in the remote network. WINS supports NetBIOS over TCP/IP (NetBT). Internet Connection Sharing (ICS) is a feature implemented in Windows Operating system to share a single Internet connection present in one computer with the other computers on the same local area network. ICS works with the help of Dynamical host control protocol of (DHCP) and network address translation (NAT).This Internet connection sharing is done by using a device with Internet access such as 3G cellular service, broadband via Ethernet, or other Internet gateway as the access point for the other devices

Managers should adapt their leadership style according to the context Essay - 1

Managers should adapt their leadership style according to the context - Essay Example This discussion will attempt to describe various reasons that compel managers to ensure that their leadership skills are properly integrated in the context of their organization’s activities. It will also describe ways by, which managers can adapt their skills in to the context of their activities and other issues that are associated with this aspect of leadership. The corpus of organizational performance has changed overtime; this has compelled various organizations to hire managers with proper leadership skills to facilitate their success in the current competitive global business platform. Organizations are becoming more hierarchical while others are showing a more collaborative aspect of operation. However, the most challenging issue emanates from the fact some organization tend to hire managers with leadership skills that do not suit their mode of operation (http://hbr.org, n.d). This has compelled most managers to be exposed in a scenario where they have to integrate their leadership skills in to the activities of the new organization and ensure they are workable. Adaptation into a new working environment is an imperative skill that is required in all working environments. This is owing to the fact that frequent economic changes may compel one person to shift from his job position to another new job position. Managers may also be transferred from one organization to another therefore creating a need for them to be in a position to adapt to their new working environment. This is an imperative leadership skill that managers must possess. Additionally, managers are organizational leaders charged with the responsibility to supervise and guide organizational activities while leading other sub-ordinate staff members. The sub-ordinate staff members are made of people with different perception on how certain issues have to be undertaken. Moreover, organizations are also

Defining And Understanding Resilience

Defining And Understanding Resilience Drawing on material from the module, critically discuss the extent to which theories relating to resilience inform our understanding of an aspect or aspects of contemporary social work. Resilience is described by Fonagy, et al ( 1994) as an ability to achieve a normal standard of development, within a challenging situation. Within contemporary social work practice therefore, support should be provided to enable children and young people to develop and be resilient when faced with adversity and trauma in their life. Rutter (2000) argues that a childs ability to be resilient when faced with hardship, is comparative as opposed to being conclusive. A child or young persons level of resilience is not a predetermined personal quality, individuals are therefore not either weak or strong. The ability to be resilient to trauma subsequently changes in relation to the situation the child is in and the protective factors which may, or may not be, in place. I will explore this further in respect of the psychosocial theories concerning resilience and vulnerability and the defensive aspects which might underpin this. I will also discuss how an increased understanding of these can be constructively applied within modern social work and the need for development of resilience in social workers, practising within a bureaucratic environment. From a psychoanalytical perspective, Freud (1923, cited in Glassman, 1995) proposes that psychological states are determined in the very early stages of life, arguing that a persons level of resilience or vulnerability may be set in place prior to the Oedipal stage. Therefore, by the end of the childhood development period, reactions such as apprehension and fear, alongside other emotive forces and mechanisms of defence have already been imprinted into a specific individual model (Thomas, 1996). A child experiencing the divorce of his parents for example, may develop polarised split views of each parent for example having positive feelings towards the mother and negative towards the father, as a method of coping with the situation (Rutter, 2000). When a situation as an adult occurs which is causing similar emotive reactions such as anxiety, an individual may fall back on this prefigured defence mechanism of splitting their views very distinctly, without perhaps analysing all of the i nformation fully. Masten Powell (2003) argue that primary structures recognised as qualities of human functioning are adaptive and have significant importance in building resilience throughout a diverse range of traumatic and frightening circumstances, for example the forming of attachment relationships which provide a sense of security. Bowlbys (1969) theory of attachment argues that the establishment of a definite connection to a primary care giver, is a significant and valuable initial relationship. Object relations theory which explores the relationship between mother and child proposes that for a child to feel positive about themselves, a warm, stable relationship is required. Bowlby (1988) proposes that a secure attachment will support a child to make confident enquiries of the world around them, developed from having a strong feeling of integration within an encouraging social structure. Attachment can be divided into secure and insecure attachments, and contains both empirical and hypothetical implications. Throughout practice therefore, a model of insecure attachment for example, can be applied in observing a childs behaviour and their possible inability to form relationships. An insecurely attached individual may have a combination of juxtaposed views such as reliance and closeness, alongside an anxiety of possible criticism and dismissal ( Holmes, 1993) . In practice therefore, an understanding of an individuals lack of connection with other people and difficulties in coping with an adverse situation can begin to be understood further within the attachment theory framework. Henderson et al ( 2007) propose that in respect of young people, the transition from childhood through to adolescence and into adulthood, is greatly strengthened by being part of a group and experiencing a sense of connectedness, as opposed to loneliness. A strong sense of ones own abilities and potential can be bolstered by being part of a social network, and also support a childs perception of school as being a constructive and positive part of life (Glover, 2009). The theory of attachment can be applied in practice not just from a psychoanalytical approach, through analysis of learned behaviour and unconscious processes, but also from a behavioural perspective which may argue that an inadequate attachment to a primary caregiver, explains the difficulty experienced in forming friendships during school years for example. Practitioners should remain mindful, however, that there are children who with a great deal of family encouragement and wider social support, still struggle to have the ability to endure the adversity and stresses which may occur in their lives (Rutter,1999). Therefore, whilst psychological theories such as Bowlbys attachment theory can aid understanding of behaviour each individual is effected by the structural factors impacting on their lives. Skeggs ( 2001) argues a sociological view, postulating that class has a significant impact on access to education for example, due to economic resources and as such restricts an individuals opportunity to develop and move forward with their lives, in a way they might wish to. Giddens (1991), in contrast, argues that people have a great deal of agency and control over their lives and therefore have the ability to make changes within their experienced structure of society. Giddens (1991) argues that we live in a post traditional society in which young people do not fall back on traditional roles which were executed by previous generations. Whilst this level of agency enables greater autonomy it may also add to the vulnerability felt by young adults, some of which may struggle more than others due to factors such as racism, stigma and disability (Banks, 2006). It could be argued therefore, that young people are attempting to move forward in life with very little sense of direction. In a postmodern society the propensity for insecurity of children is almost built into their lifestyle. Eriksons ( 1965) theory of development supports this view, arguing that cultural and social circumstances, rather than inner drives, should be evaluated. This will enable an understanding of a individuals behaviour to be gained and issues which are having a damaging effect, to be addressed. The field of child psychology which is concerned with life events, analyses the context in which the child is experiencing the significant incident. The resilience needed to cope with a life event such as divorce is ongoing. As argued by Rutter (2000) there may be particular turmoil surrounding the life event, but there is a potential for the effects of this trauma to continue throughout all other aspects of life. For example having to move home and therefore change schools, form new friendship groups and cope with the feelings of loss if a parent is no longer maintaining regular contact with the child. Therefore, whilst the divorce if the significant life event the long term loss and vulnerability felt by the child is much broader than this. A child who is experiencing a difficult home situation because of the breakdown of a parental relationship, can shield themselves from some of the mental and emotional anguish of their home life through the formation of a close relationship with an adult who is external to the immediate family unit. Howe (1995) postulates that extended family members such as aunts or uncles who positively acknowledge and nurture their abilities and unique characteristics will encourage and enable the child to form a confident and positive perception of the self, away from their traumatic situation. Achieving a feeling of ownership and confidence in ones own abilities can support the development of coping mechanisms. Fonagy, et al (1994) concur with this, arguing that in regards to building a level of resilience, the development of a strong, close relationship with a supportive adult provides an effective protective factor. In respect of contemporary social work, it is the practitioners role to support a child or young person who does not have a stable network of social support (Charles Wilton, 2004), through enabling access to recreation and social activities as necessary. However whilst this may provide support to form a social network and become part of a friendship group within a structured environment, the provision of encouragement does not have to be as definite or predetermined. The introduction of reliable, regular routines into a childs life may assist greatly in the formation of a sense of identity and well being, as recognised by Sandler et al (1989). For example, recurring daily practices in home life in respect of stories at bedtime for young children or eating meals together at a regular time. All of which help to form a feeling of stability and organisation, encouraging a sense of belonging, attachment and security. If a practitioner can apply this theory when working with a family expe riencing trauma it may serve to provide a sensation of familiarity in a life which may, in all other ways, be in turmoil. Within adult care social work also, exploration of early childhood relationships, presence of attachment and occurrence of significant life events, can be carried out, in order to fully understand how an individual has come to a particular point in their life. For example, Bowlbys (1969) study of adults in prison involved therapeutically working back through their lives, to a point in which their childhood attachments could be identified. An understanding of the construct in which the adult is existing, will enable a practitioner to gain deeper understanding, provide appropriate support and to ensure anti-oppressive practice occurs, supporting empowerment of the service user (Dominelli, 2002). Henderson, et al ( 2007) execute a biographical method in their research carried out with young people regarding their perception of well being, enabling a holistic analysis of their lives to be obtained. The benefits of this study are that the researchers tried to comprehend what the young people really understood as being imperative to their well being, through the discussion of life events which had occurred throughout the research process. Whilst the methods used by Henderson et al ( 2007) could be applied positively within social work practice in order to gain understanding of an individuals specific circumstances, practitioners should be mindful of not overlooking the complexities of situations by using the information disclosed in respect of significant life events as a straight forward method of explanation of why a young persons life has transpired the way it has. Kenny Kenny (2000) identify the possibility for patriarchal and authoritarian practice, in the application of psychosocial theories. The notion of resilience itself is subjective and therefore practitioners should be aware of their own opinion of what constitutes sinking or swimming and ensure that this personal view does not influence their judgement of a situation or an individuals capabilities ( Walker Beckett, 2003). The level of power, therefore held by social workers is vast and should be applied carefully and with an awareness of and respect for, diversity of family structures and relationships within the assessment process (Dominelli, 2002). The qualitative methods executed by Henderson et al ( 2007) in respect of gaining a biography of each participant over time, support the view of Giddens ( 1991) who argues that the self is a reflexive project. Giddens (1991) view of late modernity argues that adulthood is constructed and therefore the most significant method of establishing identity as adults, is the development of self narratives. This view is also proposed by Frosh (1991) who argues that through the development and reflexive nature of narrative construction, an individual will form the skills to endure adversities which he argues can persist throughout life. The construction of a personal narrative and the effects of life events on this, is therefore an ongoing process throughout child and adulthood. This is reflected in the research of Fonagy et al (1994) who identify that mothers presenting as resilient, provided an accurate model of the characteristics of their relationship held with their own mother. This capac ity to possess a consistent paradigm of their personal maternal attachments, which may be positive or negative, created a higher likelihood of establishing strong, secure attachments with their own children. Giddens (1991) postulates that fateful moments occur in individuals lives which shape the way their lives continue. This may be empowering or destructive dependant on the event, the timing of the event and how capable and resilient the individual is to deal with it. For example if a child experiences illness and as a consequence is unable to attend school the effects of this event can be ongoing. Being unable to sit exams, missing lessons etc, impact on their ability to integrate into friendship groups when they return to school which may result in being bullied and a change in their perception of school. The ongoing effects of this could be truancy and a lack of engagement in studying, in order to obtain qualifications and progress into further education ( Henderson, et al, 2007). In practice, gaining an understanding of an individuals narrative may present details of critical moments in their life enabling a deeper understanding of their experiences and resilience to dealing with d ifficulties . To conclude, it is clear that resilience does not represent a distinct personal attribute or quality. Children and young people may demonstrate resilience in regards to particular anxieties and traumas but feel unable to cope with others ( Rutter, 1999). Within social work practice, therefore, it is essential to evaluate how a child is placed within their family unit and also within wider society. As discussed by Gilligan (2004), the presence of other siblings, how the child functions within the family model and their relationship and interactions with family members, are significant, contextual and influential elements of a childs life and their capacity to be resilient. The impact of external environmental factors such as positive relationships with other adults, being part of a friendship group and feeling happy at school all act as protective factors in mitigating the negative elements of their life and promoting their resilience ( Werner Smith, 1992). Within the practice of contemporary social work therefore, attention should also be paid to the level of resilience held by practitioners, working with individuals in traumatic situations whilst existing within their own personal construct of relationships, family and past life events. It is imperative that practitioners are self aware in respect of their own ability to cope with the situations in which they are practising. This is an element which can at times be overlooked in regards to people working in supportive roles, who are often perceived as being highly resilient to the effects of trauma ( Coulshed Orme, 2006). In modern social work there is great emphasis placed on value and proficiency both in respect of time and finances and efficiency of practice (Rogers, 2001). The significance of emotion and resilience can frequently be underestimated within the bureaucratic schema in which social workers practice. Psychosocial theories of resilience therefore, can be applied not just in working with service users but in attempting to maintain resilience of practitioners. Word Count 2472

Organic Foods: America is Making Healthier Food Choices Essay -- Nutri

Many people in America believe that we should eat healthier foods. However, a large portion of the advertising created for food in America is focused on unhealthy foods and products, many of which are nutritionally poor and easily accessible to much of the population. This results in a contradictory ideal towards improvement of health, where individuals will constantly eat unhealthy foods and struggle to lose the weight that they will knowingly gain. If people in the modern American society were to focus more on consuming organic foods and products, people would be healthier, reducing high medical costs and improving the overall well-being of Americans. The benefits of organic foods should also be introduced to children in schools so they will be given the choice to shape their own eating habits for the future. The use of harsh chemicals in large-scale crop production is a common issue with non-organic crops. Intended to prevent pests and insects from destroying crops, pesticides and insecticides are often absorbed by the crops and are ingested by humans. Paige Parvin, a writer for Emory Magazine, addresses this issue in her article â€Å"Poison Apples†. In a study done by Chensheng Lu, assistant professor of Environmental and Occupational Health at Emory University’s Rollins School of Public Health, focused on suburban children being exposed to organophosphate pesticides in food, a chemical linked to nerve gas that is used in farming (Parvin). Lu states, â€Å"What really surprised us is that the outcome reflects the hypothesis that by switching to organic produce, there would be no exposure to pesticides,† he says. With a simple change from eating nonorganic products and gradually introducing organic foods into the diets, similar to th... ...issued by nations on GMO’s and any possible need for their use in mainstream food markets, due to lack of testing and the assurance of any negative side effects associated with consumption of these modified foods. Spears, J.F, Klaenhammer, T.R, and Petters, R.M. Genetic Engineering of Food, Feed, and Fiber: Understanding Genetic Engineering. North Carolina Cooperative Connection Service. N.d. Web. 5 Mar 2011. This article was chosen for the positive outlook towards genetic engineering of crops, which help create more crop yields, longer lasting crops and specific variants of a crop resistant to pests and diseases. Though beneficial to the Earth, the lasting complications of ingesting genetically modified foods are a highly contestable topic in America, leading to the holistic and organic food movements.

Philosophy of Christian Education

Anthony Stockton Dr. Hayes CED 2020 21 Oct. 2012 Toward a Philosophy of Christian Education Christian education is one of the most important things an individual can participate in throughout their lifetime. It is a lifelong process, beginning when we reach an age of awareness and ability to learn, and does not end until we reach our physical deaths. This is an ever-evolving progression that changes over the course of a person’s life.People have the capability to constantly grow in spiritual maturity, and it is imperative as teachers and educators to aid students in perceiving, accepting, and fulfilling the Gospel. Jesus provided the Great Commission to make disciples until the day of his return. This is something we must consider carefully and intentionally. As Christian educators, we have the responsibility of first making disciples of Christ, and secondly to prepare them for their participation in our culture and society with God’s word at the center of all they do.E ducators should have a desire for others to be transformed into the likeness of Christ. People must learn how they can know God and follow him in their daily lives. â€Å"We . . . need to be clear on our purpose and creative in our design of educational strategies and use of methods that promote the knowledge of God and a growing relationship with Him† (Anthony 25). Every faucet of the purposes and goals of Christian education should be Christ-centered and biblical.According to Michael Anthony’s book, Christian Education, â€Å"the philosophical foundations of Christian education are derived from systematic theology, which in turn emerges from biblical theology† (26). A correct observation and high view of the Bible, as well as thinking and teaching according to Christ’s view of Scripture, is the Christian educator’s ultimate frame of reference. There has to be an awareness of the indispensable theological keystone of the faith for this education t o be successful. In the Bible, Jesus says, â€Å"Sanctify them by the truth; your word is truth† (John 17. 7). Therefore, teaching with the groundwork of God’s word is teaching the truth; the Bible tells Christians how to live in this world and gives His people morals to stand by and believe. An educational philosophy that is biblically informed provides stability in the midst of the never-ending changes in our society. â€Å"The only constants in our world are God and Scripture. The Lord of the church is the Lord of theology and philosophy† (Anthony 34). Educators need to use theology and the Bible as the foundation for moving toward any philosophy in their Christian education.The purpose of my first education program is to lead people in worship of our Lord and Savior through music, which evokes their feelings and emotions as they celebrate His greatness, unconditional love, and presence in their lives. The goals for worship are for individuals to feel free to express their love of Christ and thankfulness for His mercy, grace, and eternal salvation during Sunday morning services. They will learn the powerful words to these songs, and will then be able to feel the truthfulness in them, through the indwelling of the Holy Spirit.When people worship and celebrate God, those feelings are released, which then leads to them wanting to grow even closer in their relationship with Him; one goal from this experience is for them to bring others to church, becoming witnesses and bringing people who don’t know Christ to services, thus fulfilling the Great Commission. By singing songs with words that come from the Bible, they will become familiar with verses that are God-breathed, making it a strong foundation for Christian education.The purpose of my second education program, leading small group meetings for adults, is to create a safe environment and atmosphere, where students are surrounded by not only their peers, but friends, which allows f or a positive setting to learn. The goals are to educate people regarding the Bible and God, so they will know Him more intimately; they will feel the acceptance of others, and in this emotional climate, be able to openly ask questions they have regarding Christianity that they might not feel comfortable doing in a larger group, or among people outside their age range.They will be able to both know and feel the non-judgmental attitude of the group itself, as they get to know one another more as well. Also, just as with Worship, they will want to bring others to these meetings to experience it and become more involved. Through the use of biblical materials, this program and philosophy also has a solid foundation for education. To best educate people and implement these purposes and goals I have stated, it is vital to understand how individuals learn and grow in Christian faith. At the foundation of Christian education is iblical studies and theology, but it also seeks to integrate th em with knowledge that is gleaned from the social sciences of education, sociology, and psychology (Anthony 13). By utilizing various teaching strategies that encompass learning theory systems, such as cognitive, humanistic, and behavioral, teaching objectives can be created. These explain what the educator wants the students themselves to think, to feel, and to do; however, there needs to be a personal relationship with God, as the Holy Spirit helps one to grow in the image of Christ.When studying the social sciences of education, there is an emphasis on development; humans grow, mature, and develop in varying ways throughout their life spans. In an excerpt from Anthony’s book, â€Å"cognitive development refers to the orderly changes that occur in the way people understand and cope with their world. Cognitive theorists are concerned with how we know, that is, with how we obtain, process, and use information† (68).Jean Piaget first proposed the design of this type of growth, and maintained that there are four major periods, each age-related, of cognitive development: sensorimotor stage, preoperational stage, concrete operations, and formal operations. By knowing these stages in cognitive development, one can apply the concepts in teaching. The educator must focus on what the person at each stage can do, as well as avoid what they can’t understand. They need to be intentional and effective in comprehending and meeting learners’ needs. Moral development is also an important issue that Christian educators need to understand.Bonnidell Clouse noted four general approaches to this type of development: psychoanalytical, learning/conditioning, cognitive/moral reasoning, and moral potential (Anthony 73). The psychoanalytical approach was advocated by Sigmund Freud, and describes development that occurs due to psychological conflict between the ego, superego, and id, where morality results from conflict; B. F. Skinner supported the approach of conditioning, where development occurs due to the individual being exposed to external stimuli and subsequently conditioned with a behavioral response to a given situation, and morality results from action.The cognitive/moral reasoning approach that Jean Piaget proposed is a process that accompanies cognitive/intellectual development, where â€Å"higher† levels of authority make moral decisions, concluding that morality results from knowledge; the fourth and last approach of moral potential was campaigned by Carl Rogers, where development of morals is innate to humanity and is progressed through the process of self-actualization as needs, basic and advanced, are fulfilled, and morality results from potential. These four approaches to moral development are based on the scientific perspective.Though Christian educators have both praised and ridiculed these theories, one of the basic criticisms is that the definition of morality is simple, narrow, and solitary. â€Å"Christi an educators have often turned to Scripture and theology to supply the foundation for understanding moral development. Dennis Dirks notes the development framework presented in the metaphor of moral growth throughout the New Testament, as well as the concepts of internalization of values and moral transformation† (Anthony 78).Donald Joy describes moral development’s path as a pilgrimage, and believes it must have insights from theology, not just the social sciences, in order to provide a comprehensive view of the process. Since Christian educators have incorporated both the theorists’ approaches, as well as the theological ideals, their concept of moral development is more comprehensive. â€Å"It must include reasons, actions, and characters that require knowledge, behavior, virtues, and principles† (Anthony 81). Faith development is another issue for Christian educators to take into consideration.James W. Fowler is the founder of this theory, devoting his time to studying the nature of faith and its development. In order to understand his theory, it is necessary to realize that his primary conceptualization of faith is generic; he assumes that all human beings have some form of faith that proceeds through a rather predictable process of development (Anthony 83). According to Michael Anthony, â€Å"in faith development, a distinction is made between beliefs and faith. Beliefs are significant means by which faith is expressed.But faith is much deeper and includes both conscious and unconscious motivations† (83). Fowler defines faith in terms of loyalty and trust, such as devotion to ideas or persons that have worth to us (â€Å"centers of value†), loyalty to power centers in life that give a sense of security, and devotion to a â€Å"master story† that gives direction and hope in life (84). The calling of God upon believers is emphasized in relating the development of faith to Christianity, where vocation is the r esponse a person makes.The image of God is placed within each person, and the stages of faith symbolize one way in which the potential of that image unfolds. Conversion and transformation are two aspects of faith growth that correlate with New Testament teachings. These insights contribute to the process of Christian education, but one must also be aware of its weaknesses and limitations. â€Å"God’s perspective as given in Scripture must be the ultimate and most important benchmark by which faith development is measured† (Anthony 89).However, this theory does imply that the faith of adults has the potential to continue to develop throughout adulthood; this is a valid reason to include adult ministries, such as small group meetings, to the educational ministry of the church. As mentioned previously, there are multiple learning theory styles which are used to help teach the student and attain the goals and objectives in a curriculum, three significant ones being cogniti ve, humanistic, and behavioral theories. These describe ways in which people learn and grow, and should be utilized by Christian educators. While specific theories of learning do not translate directly into principles of teaching, they provide maps and compasses to aid the inexperienced teacher-traveler in charting the course to learning success† (Anthony 101). Educating is more than expressing subject matter and demonstrating the knowledge of the teacher; it is facilitating the convergence of the needs of the learner, as well as subject substance. These two aspects fall into three fundamental areas of life: what we think (meaningful understanding), what we value (personal convictions), and what we do (skilled behavior).There needs to be from any learner/student a deeper understanding, the development of appropriate values, and the sharpening of skills (101). The first primary area of life, what we think, involves the cognitive theory of learning. These focus on the internal m ental processes people use in their effort to make sense of the world. Cognitive theorists view learning as a reorganization of perceptions. Michael Anthony describes perception as â€Å"the meaning we attach to information we receive from the world around us. Perceptual reorganization allows learners to develop a clear understanding of the subject† (104).Jean Piaget is one advocate and leading thinker in this area, and describes the process through the use of terms, such as organization (the natural tendency to make sense of experiences by incorporating them into logically related cognitive structures), schemes (the cognitive structures produced as a result of this development process), equilibration (the natural tendency to maintain a balance between what one already knows and what one experiences in the world), and adaptation (the natural process of adjusting our thinking or environment so that balance exists between what we know and what we experience).Assimilation and ac commodation are two parts of adaptation; assimilation interprets experiences so they fit what we already know, and accommodation adjusts schemes so they fit what we experience (105). Another advocate in cognitive learning theory is Jerome Bruner, and â€Å"he believes the goal of teaching is to promote the general understanding of a subject and that the facts and relationships children discover through their own explorations are more usable and tend to be better retained than material they have merely committed to memory† (Anthony 105).In his research, he proposed that this discovery type of learning increases and creates improved problem-solving skills and a higher degree of confidence in the capability to learn as they â€Å"learn how to learn. † He proposed the structuring of subjects, allowing them to be arranged in a way to aid in student’s learning; this structure is facilitated by the three components of presentation, economy, and power. Discovery learnin g highlights student’s activity, initiative, and solutions. Later, Bruner’s theory was adjusted to include more teacher intervention and direction, called directed discovery.The second learning style incorporates what we value, and is called the humanistic theory. â€Å"Educational humanism, or affective education, emphasizes the affective domain of learning: receiving (personal openness), responding (personal response), valuing (personal conviction), organizing (personal value system), and characterizing (personal lifestyle)† (Anthony 107). In this theory, true human learning involves attitudes, emotions, and values, stressing the uniqueness of each learner. Three leading psychologists who influenced humanistic methods of education are Abraham Maslow, Carl Rogers, and Arthur Combs.Maslow focused his efforts on those who were mentally healthy (self-actualized), and believed that children make wise choices for their own learning when given the opportunity; teache rs assemble meaningful learning conditions, and students select from those they find personally valuable. Rogers created person-centered methods in his counseling as a psychotherapist, which revolves around the client, standing against directive therapy, which revolves around the counselor. â€Å"He focused more on phenomenology (the world as it is perceived by individuals) than reality (the world as it may actually be).In his view, teachers should trust students to do their work to the best of their ability and provide opportunities for learning† (Anthony 107). According to Rogers, students will then take responsibility for their own learning. Combs, in his specific beliefs on humanistic learning theory, accentuated and advocated that teachers should serve as catalysts for learning, facilitating the experience for students. His research is similar to Bruner’s, but Combs placed more emphasis on sharing personal views and less on objective problem solving. For Combs, me aning is not inherent in the subject matter; it is the individual who instills subject matter with its meaning. His dilemma was not how to present subject matter but how to help students derive personal meaning† (Anthony 107). All three of these specific theorists, Bruner, Rogers, and Combs, explored and researched certain ideals that encompass, in the broader view, humanistic principles of learning. The third and final fundamental area of life, what we do, involves the behavioral theory of learning. Ivan Pavlov (Classical Conditioning), E. L.Thorndike (Connectionism), and B. F. Skinner (Operant Conditioning) are three of the most prominent theorists of behavioral learning. Pavlov is the founder of classical conditioning, discovering through experimenting with dogs a connection between food, the stimulus, and salivation, the response; this connection is called a stimulus-response bond. â€Å"This link provided the foundation for behavior modification – behavior shaping as well as brainwashing . . . classical conditioning in classrooms focuses on involuntary behaviors that are outside conscious control† (Anthony 102).Thorndike, the second theorist, is known as the father of educational psychology. He demonstrated the mechanism by which new responses are formed, whereas the work of Pavlov emphasized only simple reflex actions; Thorndike showed that stimuli occurring after a behavior had an influence on future behaviors. He postulated three laws of learning: The Law of Readiness (stating that learning proceeds best when learners are prepared to respond), The Law of Exercise (stating that repetition strengthens the timulus-response bonds), and The Law of Effect (stating that any response followed by pleasure or reward is strengthened, whereas any response followed by pain is weakened). Skinner created the Operant Conditioning theory of behavioral learning, and it was an expansion of Thorndike’s Law of Effect. â€Å"In classical conditio ning, responses are involuntary and elicited by specific stimuli. Operant conditioning emphasizes the acquisition of new behaviors as organisms operate on their environment in order to reach goals. The responses are voluntary and emitted by people or animals† (Anthony 103).Skinner used pigeons in his research, placing them in observation cages; when they behaved desirably, he reinforced that behavior with food, and was able to teach them through providing reinforcing stimuli for the desirable behavior. This educational application is seen best in programmed instruction. Learning programs begin with a desired competency, and then breaks this competency into small steps of learning. â€Å"Programmed instruction maximizes learner reinforcement (reward) and also the amount of interaction between learner and information† (Anthony 103).These systems are used today, found in textbooks as well as some forms of Christian school curriculum (the Accelerated Christian Education). P avlov, Thorndike, and Skinner all used behavioral theories of learning, expounding on certain principles and ideas that are useful in teaching for educators. In terms of my own leading and teaching of Christian education, my focus will be through the use of Christ-centered music as I direct the worship and praise team for my church congregation; I will also teach and lead a more specific group of people, adults, in small group meetings.For the contemporary service, Sunday mornings at my church will begin and end in worship, with the people singing and praising God. There will be more modern and upbeat Christian music, with a live band that I intend to lead, and this genre of music is tailored toward the younger generations who attend this service; there will still be the formal church service, where hymns are sung, creating a more somber atmosphere for the elder generation who grew up and are accustomed with this type of music.I believe through the use of songs that are more recogni zable to the individuals, such as singing the music that many of the attendees (youth, teenagers, and young adults) love to sing with and listen to on Christian radio stations, they (the students, in this setting) will be inspired and feel the calling to lift their voices and hearts to the Lord in praise of His Glory. This is something our Heavenly Father has asked us to do, and pleases Him as a part of ministry. In 1 Chronicles 25, this entire chapter is devoted to listing â€Å"The Singers†, and was called a service. All these men were under the supervision of their fathers for the music of the temple of the Lord, with cymbals, lyres, and harps, for the ministry at the house of God† (1 Chr. 25. 6). As many of the verses of these songs come directly from scripture in the Bible, they will be singing out His words and the teachings from the Master Teacher, Jesus Christ; for people who don’t recognize the songs, the musicality and melodies themselves being current and upbeat will allow them to have a more enjoyable experience, while praising God through worship, as well as learning the powerful words.Music is something most everyone cares for, to varying degrees, and has the ability to evoke strong emotions and feelings. By leading this band, I will also be able to teach the members who are involved in this service to the church and its congregation, incorporating their ideas and musical talents into the worship each week. When I think upon social science’s influence concerning different learning theories for teaching, such as cognitive, humanistic, and behavioral learning as mentioned previously, I seem to be drawn more toward the humanistic view of how people learn.John Dewey is considered the father of progressive education, though the foundation had been laid for a new approach toward the teacher-learner process prior to him by people like Luther, Melanchthon, and Sturn, all of whom had advocated the importance placed upon students to have a firm understanding regarding education. Humanistic theories of learning are more personal, accenting the significance and role of feelings and emotions, which I find imperative for both the teacher and student in learning and teaching. Arthur Combs was one of the most prominent promoters of this theory. Effective facilitators, according to Combs, are well-informed, sensitive, believe in their students’ abilities to learn, have a positive self-concept, and use many methods to engage students in the learning process† (Anthony 107). The tendency is a desire to create an environment for learning that is free from fear, punishment, harsh discipline, and manipulative methods. In my opinion, these are all concepts that Jesus Himself used in his own teachings, and I will use this technique in my own teachings, and in leading worship for my church.I will also teach individuals attending small group meetings each week, leading them with the use of, and emphasis on, God ’s word. This will include a more particular set of people, as these meetings will be for young adults; the ages will range anywhere from 18 to 40’s, though most will be in their 20’s and 30’s, as there are small group meetings already created specifically for both the much younger adults, as well as for the older ones. However, anyone over the age of 18 will be welcomed.These meetings will be a much smaller target area in my teaching and leading, unlike worship, which includes the entire congregation – children, teens, young adults, as well as older adults who might choose to attend the contemporary service. This smaller setting will allow for individuals to be able to participate in discussions more easily than if it were a larger group; it will permit for one-on-one talks between myself and them (the students), as well as fellowship among themselves.Also, biblical material will be used, such as videos pertaining to themes that will be set up (la sting anywhere between four and eight weeks each); by utilizing courses created by other pastors and teachers, there will be the added benefit of learning important issues and studies through others, and I will lead the group in any discussion questions that arise. At these meetings, we will begin by â€Å"breaking bread† through eating together. Each individual will contribute, if able, to the meal every week; this will allow for great fellowship and people becoming more familiar and friendly with one another.As this will help to make everyone more comfortable prior to the lesson, I believe this will aid in the students being more open, feeling an acceptance from the group and encouraging them to ask questions and become involved in the studies. In the Gospel of Luke, The Last Supper is described, with Jesus speaking to his apostles. â€Å"And he took bread, gave thanks and broke it, and gave it to them, saying, ‘This is my body given for you; do this in remembrance o f me. ’ In the same way, after the supper he took the cup, saying, ‘This cup is the new covenant in my blood, which is poured out for you. † (Luke 22. 19-20). In the same way that Jesus shared meals, especially his last meal – which we observe during church services as Communion – we will share meals together as a group. My teaching strategies for these small group meetings will be more intense than for leading worship, as there will be studies and further available learning material. With this in mind, I believe that the cognitive theory of learning will be helpful, as I intend to aid my students in thinking through issues and discussions that will be presented.As mentioned, both Jean Piaget and Jerome Bruner shaped this learning theory system, and many fundamental perspectives come from them. Piaget believed that intelligence is not something given to people, and that understanding is structured by them; Bruner also proposed subjects are to be orga nized and structured, determining the primary principles and their relation to one another. Cognitive learning was also found in Gestalt psychology, which is the view that learning takes place best when people see the relationship or pattern of one element to another. Gestalt psychology stressed the significance of relationships in the learning experience. Three early German gestalt psychologists were Ernst Mach, Max Wertheimer, and Wolfgang Kohler† (Anthony 104). Ernest Mach held that human learning was determined by interaction between the world and our perception of it, not by mechanical bonds, like behaviorist John Watson believed. Max Wertheimer proposed that focusing on the smallest parts of learning was pointless, instead embracing that the whole gave meaning to the individual parts.Wolfgang Kohler, through his experiments with chimpanzees, demonstrated learning by insight, while behaviorist E. L. Thorndike had emphasized trial and error learning instead. â€Å"These d ifferences underscore the vast divide between behavioral and cognitive learning theories† (Anthony 104). Through reading about the various learning theories, I have found that, in my opinion, there is truth and insight to be gained from each; the cognitive, humanistic, and behavioral theorists’ opinions, research, and viewpoints all have the ability to aid in teaching.I want to take into account all I have myself learned, and use it in my small group meetings. I feel there is no need to limit myself to one specific theory or belief, but to acknowledge the various ideas that have been put forward by these prominent thinkers, and use them in my own teaching; people are different, and therefore learn in different ways, so having a firm grasp of these techniques is an asset in leading.While I intend to use the social sciences and psychological theories of learning in my teaching, I know that the ultimate teacher is Jesus Christ. He taught us to love one another, give forgiv eness to our enemies, to teach through gentleness and understanding, as well as giving us the Fruits of the Spirit; â€Å"But the fruit of the Spirit is love, joy, peace, patience, kindness, goodness, faithfulness, gentleness, and self-control† (Gal. 5. 22-23).I want to be led by the Holy Spirit, walking the path that God has set for me, and allowing Him to work through me as I teach His word and promises to others. I will continue in my prayers, striving everyday for a closer relationship with Jesus, and ask Him to give me the wisdom to teach and lead; as I dig deeper into the Bible, I myself will increase in spiritual maturity. There must be attentiveness to this indispensable and crucial theological keystone of the faith for my Christian education program to be successful.In conclusion, my philosophy toward a Christian education through the medium of leading worship with Christ-centered music for my church congregation, as well as in teaching small group meetings for adult s, has been discussed throughout this paper. By creating my purposes and goals for students in these areas of teaching and leading, and by having a solid foundation in biblical principles, I address how I want my students to perceive, accept, and fulfill the gospel; that is, to think, to feel, and to do.These teaching and learning strategies encourage students to think (cognitive theory) about God, His word, and the promises He made to His children, to feel (humanistic theory) His presence in their lives and be on fire for the Lord, and to fulfill (behavioral theory) the Great Commission through going out into the community and spreading the good word, The Holy Bible, as well as developing a closer relationship with Jesus and allowing the Holy Spirit to guide them in their life decisions.These goals use the multiple social sciences’ theories on learning, and how people grow in their Christian faith; my beliefs and opinions on how to lead and teach in Christian education are a lso expressed, as I state the need to incorporate all information available to educators for the best outcome in teaching students.The most important aspect is to have a Christ-centered learning experience, utilizing biblical material and God’s word; this will have the most impact, as the Lord will lead me in leading and teaching others. Works Cited Anthony, Michael J. Introducing Christian Education: Foundations for the Twenty-first Century. Grand Rapids, MI: Baker Academic, 2001. Print. The Holy Bible. Intl. Bible Society. Grand Rapids: Zondervan, 1984. Print. New Intl. Vers. Philosophy of Christian Education My Philosophy of Christian Education Isaiah 54:13 â€Å"all your children shall be taught by the LORD, and great shall be the peace of your children. † Introduction: Upon examination of Jesus’ life and ministry here on earth, I find it to be very fascinating that He successfully engaged in a plethora of professional fields; including that of teaching. In fact, He holds the title of Master Teacher. He was indeed a highly sought after teacher whose passionate and holistic approach to the vocation of education is the basis of my philosophy of Christian Education.The Ohio Department of Education, Center for the Teaching Profession describes the Master Teacher as one who, respects students’ diversity, is knowledgeable in the content area, practices effective assessment, effects plans, communicates with all stake holders, promotes a learner friendly environment and assumes responsibility for his/her professional growth and development. Christ the master teacher exhibit ed all these qualities and as a Christian Educator we all should too. It is on this foundation that I will seek to base my philosophy of Christian Education.According to Guillemin and Beck (1998), a Christian philosophy of education is, â€Å"one that is determined by scriptures and bordered by the parameters, educational purpose, educational provider, the learner, curriculum or content and teaching,† giving rise to four specific tenets. These four tenets to the Christian Education process consist of; the learner, the teacher, the curriculum and the teaching process. Therefore in formulating my Philosophy of Christian Education, I will use scriptural references to support the four aforementioned tenets of the Christian Education process. The Body The LearnerThe Learner in the Christian Education process may either be a child in the home, a student in the formal classroom setting, or an adult member of a congregation. Sociologists have described the family as the first agent o f socialization and therefore parents are the first educators. God has given parents the mandate to, â€Å"Train up the child in the way he should go and when he is old he will not depart from it,† (Proverbs 22:6) also in Deuteronomy 6: 6-7 the Lord gave clear directions regarding the commandments; â€Å"These commandments given today are to be upon your hearts. Impress them upon your children.Talk about them when you sit at home and when you walk along the road. When you lie down and when you get up. †(NIV) The word parents can be extended to include other persons in the society who are responsible for guiding and facilitating learning. This includes teachers and so we too have this mandate in relation to the child in the formal classroom. The Christian teacher even more so, as we must not only facilitate the contents of the secular curriculum but also be able to integrate Biblical principles effectively so children can come to realize their purpose in God’s wo nderful plan.In college I was taught to do everything to avoid teaching ‘Christ’ in the classroom. This was frowned upon as being indoctrination and so, in the schools I have worked before, all that is done to fulfill the mandate is devotional exercise and even then, children are not mandated to attend. Some of these children demonstrated total lack of respect for persons in authority, lying, stealing, cheating among other despicable acts and when there is no intervention some ended up being juvenile delinquents. It was never intended by God for children to behave, nor end up in such a manner.After all, Jesus said, â€Å"Suffer the little children to come unto me: forbid them not, for of such is the kingdom of heaven. † (Matthew 19: 14). Teaching about Christ definitely should be the job of all teachers. It is for each learner too, to study to show himself approved to God. (2 Timothy 2:15). As leaders we are commanded by God to feed his sheep. (John 21:17). The G reat Commission is found in Mathew 28:19, Jesus gave His disciples direct instructions to go and teach all nations, make disciples, teach them to obey all the commandments that were given unto them.Therefore due to the reciprocal nature of the teaching learning process, I am of the view that both learners and teachers do have a very critical and equally important role to play, to guarantee success and the fulfillment of God’s plan. The Teacher Consequently, the teacher is accountable to God for the quality service that is offered to those in his/her care. In James 3:1, 2 it is stated, â€Å"Not many of you should presume to be teachers, my brothers, because we know that we who teach will be judged more strictly†¦. As teachers of Christian education we should seek to emulate Christ as we facilitate learning. He is the Master Teacher who exhibited consistent leadership. Jesus sought to his listeners’ wellbeing showing how much He cared; for example in the feeding o f the multitude. (Mathew 4:13-21). Jesus as teacher also aided his students in their decision making process. In Proverbs 11: 14, He clearly establishes the importance of guided decision making. â€Å"Where there is no guidance, a people falls, but in an abundance of counselors there is safety. He also in His many uses of parables made his teachings very applicable to real life situations, therefore understandable. He was a very innovative teacher who sought to influence, transform and empower people. His infinite knowledge made Him experienced in teaching. As Christian educators we too must have some experience of the power of the Holy Spirit in order to be able to communicate fully, to the learners, the importance of, and the difference having Jesus Christ in their lives can make. Therefore it is my conviction that, Christian Education is best taught by Christian Educators.Paul in first Corinthians one lived as a teacher in Christ and therefore was able to tell his charges, †Å"Be ye followers of me, even as I am also of Christ. † Therefore we should model Christ’s teachings as well as teaching them. Dr. Paul Cates, in his article entitled Transforming Teachers- Christian Philosophy of Education, postulated that, â€Å"The teacher is the communicator of truth, he must therefore be openly and boldly a Christian. † Teachers must be aware that teaching is a call to ministry. Teaching is one of the foremost gifts of the Holy Spirit. 1 Corinthians 12:28.It is to be used for the edification of the church or, in this case the learner. The Curriculum Additionally, it is my belief that the Bible forms the very core of the Christian Education curriculum. Guillemin and Beck (1998) argue that; â€Å"the content or curriculum of Christian Education is simply truth. Unless we know God we cannot know anything correctly. God is best understood through the revelation of Himself in scripture. Christian Education which is truly genuine begins, proceeds and ends with the concept of divine revelation. All other truths must be scrutinized by it. Author, Craig Rose uses the passage of scripture found in 1 Colossians 17 â€Å"In Him all things consists† as the premise on which his book titled â€Å"All Things Consists in Him: Teaching Christianity Using Biblical Integration† is based. Rose purports that; â€Å"we as Christian educators, should not relax within our safe environments, but should be diligent to utilize the opportunities provided to train up Spirit-filled students who know how God can use them in each of their respective fields of study-from athletics to acting, from law to literature and from math to ministry.Each field of study needs Christians who really believe they are to be identified with Christ first and their profession second-such as a Christian engineer, a Christian football player, and a Christian playwright. † This is similar to how we are recognized by both our first and last names. This will entrench in their minds and in the minds of their peers and colleagues that they are different, set aside, being built as a spiritual house, a holy priesthood, to offer spiritual sacrifices acceptable, to God through Jesus Christ. (I Peter 2:5). He further argues that the Bible is both the foundation upon which ideas are presented and the filter through which they are explored. For every topic in every subject a principle from the Bible can be had. It therefore stands to reason to say God supports the knowledge that we pass on to our charges. In Social Studies for example; there are principles to support every strand, and every topic within each strand. In the History strand we see where God wants us to develop a positive attitude towards historical events.We must learn about and pass on knowledge of these. Deuteronomy 31:19, 21, 22 shows God instructing Moses to, â€Å"write down this song for yourselves, and teach it to the children of Israel; put it in their mouths, that t his song may be a witness for me against the children of Israel. † There’s no doubt that God believes in the teaching of History, after all He was the one who inspired men to write the Bible which is to date, the greatest History book ever written.Similarly there are scriptures to support the other strands of Social Studies; geographical principle proves that God is responsible for the contours of the earth†¦Job 26:10, â€Å"He drew a circular horizon on the face of the waters, at the boundary of light and darkness. † For economics in dealing with money and possessions He reminded us in James 1:17, â€Å"Every good gift and every perfect gift is from above, and comes down from the father of lights†¦. † For the strand Government, we see where nations, governments and authorities were created by God and maintained by Him for His ultimate purposes.Job 12:23, â€Å"He increases the nations, and destroys them: He enlarges them and then straightens th em again†¦Ã¢â‚¬  In Language Arts there are Biblical principles and scriptures to also support each strand namely, Reading, writing, listening and speaking. God spoke the world into being and that is a miraculous use of language. The Bible totally supports the curriculum within the school and therefore it is for us as Christian educators to infuse our lessons with these principles thereby facilitating the plan of God that young men and women will come to serve Him in their youth. The Teaching ProcessGuillemin and Beck (1998), identified three principles in the teaching process. â€Å"Firstly, the objective content of truth directs us to the objective methods of teaching. Secondly, the fact those students are persons, demands personal approaches to teaching. Thirdly, the purpose of conforming to Christ’s image focuses the process of teaching on evaluation† As educators we are challenged to present objectivity in a relatively subjective world. While we train studen ts to reason and confront their biases, it is also important that they are made to understand that there is objective truth to be learned.Deuteronomy 6:25 provides a Biblical response to the question of subjectivity. In his book â€Å"Reclaiming the Future of Christian Education,† Greene (2003) declares, â€Å"Knowing God in and through the creation is what is important, and students must be helped to explore the creation along the lines of their own gifts. † Greene stresses, that it is important to reawaken to the biblical view of life and reality, we dare not fail to train our children, whether in Christian schools or in Christian home schools, in a transformed, biblical consciousness. † In other words, we must return to a biblical worldview.I firmly believe that it is imperative for Christian educators to model the desired behavior of the student in his/her care. Teachers must first live transformed lives if they desire to positively impact young lives. It is important for them not to send mixed signals to the students, as this will only contribute to chaos and confusion. And will negatively impact the teaching/ learning process. According to Dr. Cates, The Bible being the foundation of the school reveals the threefold features of Christian Education as, a purpose, method and result. The purpose is to put the believer into right relationship with God, man, self and his surroundings. † The method is the spirit’s support with the adoption of Biblical truth to the believer’s life resulting in a mature believer who is able to live a life in accordance with the teaching of God’s word. He postulates that; â€Å"Christian education is a process of guided learning where the teacher and the Holy Spirit combine efforts to help the learner, to spiritually grow and mature, to more and more conform to the image of Christ. † ConclusionIn conclusion, I wish to reiterate that a philosophy of Christian education must be based on a revelation of God through His word, His creation and His Son Jesus Christ. It includes the learner, the teacher, the curriculum and the teaching process. I deem it pertinent to also superimpose the Master teacher characteristics of Jesus; to be patterned by today’s Christian Educators. As we continue to impact lives and facilitate transformation, growth and development. It is of paramount importance to practice consistent leadership, focused in collaboration and a distinguished teaching.Finally it is important to always remember that we touch the future because we teach. Therefore, â€Å"all our children shall be taught by the LORD,† Through us, â€Å"and great shall be the peace of our children. † References Edlin, R. (2003). Core beliefs and values of a Christian philosophy of education. In J. Braley. , J. Layman. , & R. White. (Eds. ), Foundations of Christian school education (pp. 69-81). Colorado Springs, Colorado: Purposeful Design Publications. Greene, E. (2003). Reclaiming the future of Christian education.Colorado Springs, Colorado: Purposeful Design Publications. Guillermin, P. , & Beck, D. (1998). Christian philosophy of education. In P. Kienel. , O. Gibbs. & S. Berry. (Eds. ), Philosophy of Christian school education (pp. 105-129). Colorado Springs, Colorado: Association of Christian Schools International. Rose, Craig D. ( nd. ). In Him All Things Consist, Teaching Christianly using Biblical Integration Websites http://www. aiias. edu/ict/vol_21/21cc_377-394. htm http://www. transformingteachers. org/index. php? option=com_content&task=view&id=37

Project on Spy Ear

CHAPTER 1 INTRODUCTION, CIRCIT DIAGRAM AND WORKING INTRODUCTION Spy ear is the devices which converts low power audio signal to high power signal and gain. It can be used in Theaters , Concert halls, Lecture rooms, Trains, Court houses, Conference rooms, Embassies, Gaming facilities, Recording studios, Aircraft , railways ,bus station etc. With this sound amplifier, you can now hear things crystal clear that you could never hear before. Spy ear is very easy to use, just put the ear buds in your ears – aim the Spy Ear towards what you want to hear and things are heard crystal clear.Spy Ear has adjustable volume control, which amplifies sound up to 50 decibels. Spy ear is also great for watching TV late at night, while your spouse sleeps you can keep the sound on the TV way down and still hear clearly. In spy ear circuit the most important part which is used to amplify the ckt is An IC named LM386N, which is a low sound amplifier, it amplifies the sound which is received by the condenser mic connected in the ckt. The LM386 is a power amplifier designed for use in low voltage consumer applications.The gain is internally set to 20 to keep external part count low, but the addition of an external resistor and capacitor between pins 1 and 8 will increase the gain to any value from 20 to 200. The inputs are ground referenced while the output automatically biases to one-half the supply voltage. The quiescent power drain is only 24 mill watts when operating from a 6 volt supply, making the LM386 ideal for battery operation. Spy ear is widely using in the spy works. Many spy agencies, National Security Agencies using both wired and wireless spy ears to hear the private conversation and to cought any illegal person doing any illegal work.CIRCUIT DIAGRAM [pic] WORKING What binoculars do to improve your vision, this personal sound enhancer circuit does for listening. This lightweight gadget produces an adjustable gain on sounds picked up from the built-in high-sensiti vity condenser microphone. So you can hear what you have been missing. With a 6V (4? 1. 5V) battery, it produces good results. a small signal amplifier is built around transistor BC547 (T1). Transistor T1 and the related. components amplify the sound signals picked up by the condenser microphone (MIC).The amplified signal from the preamplifier stage is fed to input pin 3 of IC LM386N (IC1) through capacitor C2 (100nF) and volume control VR1 (10-kilo-ohm log). A decoupling network comprising resistor R5 and capacitor C3 provides the preamplifier block with a clean supply voltage. Audio amplifier IC LM386N (IC1) is designed for operation with power supplies in the 4-15V DC range. It is housed in a standard 8-pin DIL package, consumes very small quiescent current and is ideal for battery-powered portable applications. The processed output signal from capacitor C2 goes to one end of volume control VR1.The wiper is taken to pin 3 of LM386N audio output amplifier. Note that the R6-C4 netw ork is used to RF-decouple positive-supply pin 6 and R8-C7 is an optional Zobel network that ensures high frequency stability when feeding an inductive headphone load. Capacitor C6 (22? F, 16V) wired between pin 7 and ground gives additional ripple rejection. The output of LM386N power amplifier can safely drive a standard 32-ohm monophonic headphone/earphone. Assemble the circuit on a small general-purpose PCB and house in a suitable metallic enclosure with an integrated battery holder and headphone/ earphone socket as shown in .Fit the on/off switch (S1), volume control (VR1) and power indicator (LED1) on the enclosure. Finally, fit the condenser microphone (MIC) on the front side of the enclosure and link it to the input of the preamplifier via a short length of the shielded wire. CHAPTER 2 COMPONENTS AND TOOLS USED COMPONENT USED COMPONENT NAMESPECIFICATION QUANTITY RESISTANCES R14. 7K? 1 R2330K? 1 R333? 1 R4680? 1 R5150? 1 R610? 1 R71K? 1 R810? , 0. 5W1 CAPACITANCES C110n(Non P olar)1 C2100n(Non Polar)1 C347 µ(elec. ) , 16V(Polar)1 C41000 µ(elec. ) , 16V(Polar)1 C54. 7 µ(elec. ) , 16V(Polar)1 C622 µ(elec. ) , 16V(Polar)1 C7100n(Non Polar)1C8100 µ(elec. ) , 16V(Polar)1 C9100n(Non Polar)1 C10470 µ(elec. ) , 16V(Polar)1 VOLUME CONTROLLER VR110K? 1 TRANSISTOR T1BC5471 ICLM386N1 IC BASE8-PIN1 LED1 CONDENSER MIC1 EARPHONE32? 1 BATTERIES1. 5V4 BATTERIES HOLDER1 HOLDER CAP1 SWITCH1 PCBSINGLE SIDED1 TOOLS USED IN PCB DESIGNING COMPONENTQUANTITY SAW1 FeCl31 [pic] MULTIMETER1 [pic] HAND DRILLER1 [pic] SOLDERING IRON1 [pic] SOLDERING PASTE1 [pic] SOLDERING WIRE1 [pic] CHAPTER 3 PREPARATION AND PROCESS OF PCB DESIGNING Materials: ? Liquid solutions:- Ferric Chloride (Fecl3), Ferric chloride solution,  about 1 liter/ 0,26 gallons Lacquer thinner Safety solutions:- Safety goggles, Soft plastic brush, Clothes iron, Rubber gloves ? layout solutions:- Software for drawing layout. Like:- 1. P-Spice 2. ExpressPCB 3. PCB Wizard 3. 50 Pro 4. EDWinXP ? Good quality magazine pages (A4 Size) (Glossy paper), ? Laser printer ? Scrubbing pad ? Good ventilation ? Paper towel, ? Tin snips ? Drill or rotary tool ? PCB drill bits ? 5-gallon plastic pail full of water ? Single sided 1 ounce copper clad ? A plastic container the board will fit in PREPARATION Print the bottom side layer on a piece of paper from a high quality magazine or Glossy paper.Use one actual page from the magazine or Glossy paper, the thicker and shinier the magazine paper the better, but do not use the cover. You must use a laser printer, not an inkjet. If your printer uses ink cartridges and not toner cartridges, it will not work. If you do not have a laser printer, you can work around this by printing to white paper and using a photocopier set to the darkest setting to copy the layout to the magazine paper. If the paper jams in the printer, you are not using a thick-enough magazine pages. Again, do not use the magazine covers, as they do not work.Magazine pages are used because they work well, and they are cheap! The reason they work is because the paper is very glossy and the toner does not adhere well to the glossy pages. The printing used on the magazine page is ink and it does not come off, but toner does. Toner  is actually a plastic polymer, and different toners may yield varied results. In our experience, a genuine HP toner cartridge was used with great success. The sole purpose of the toner is the protect the copper below it from etching away; you only want the uncovered areas to etch. Next, wash your hands to remove any oils.Keep handling to a minimum once the pages are printed and do not touch the laser printing with your fingers; this could get oils on the printing. Keep pages as flat as possible. [pic][pic] Very carefully, remove the copper clad from the packaging. Do not touch the copper surface for the same reason as above. You can cut the copper clad to size using a tin snip if needed. Use the scrubbing pad to gently buff the surface. Do not use steel wool because it will embed steel into the copper. Clean off the residual dust with a slightly damp paper towel. [pic] Find a hard, very flat, sturdy, heat resistant surface.Empty the water out of the clothes iron and set the iron on the hottest setting. Allow the iron to get hot. [pic] This is both side of a piece of copper clad. Place the blank side facing down and copper side facing up. Align printing/paper onto copper clad board with the printing facing the copper. Do not allow it to move. [pic] [pic] Firmly press the iron onto the back of the magazine paper, sandwiching it between the copper clad and the iron. Pressing hard without moving the iron, hold the iron perfectly still for one full minute. Do not move the iron at all during this minute, and push hard, really hard!Then, for four more minutes, slowly move the iron around making sure to put a lot of pressure on the paper, but not allowing the paper to slide on the copper. When done, let the board fully cool b efore you move it at all. This will allow the toner to adhere to the copper and prevent you from being burned. Put the board in cold water and let soak for five minutes. After five minutes, try to peel the wet paper from the board leaving only the toner/print from your laser printer. Only the toner should be left adhering to the copper. If the paper does not come off easily, let it soak in the water for a while longer.If necessary, rub with your finger to remove any paper, leaving only the toner. It’s ok if there are a few excess paper fibers stuck to the toner. [pic][pic] [pic] If you find not every trace adhered to the copper clad or it is misaligned, use lacquer thinner and paper towel to clean the toner from the copper board and start over. If the traces look good then move on. Inspect the traces carefully, however, because what you see now will be your finished product. [pic] In a well-ventilated area with a fan, add hot water to a plastic container. Gently pour in 1-cup Fecl3, to create the etching solution.Always wear goggles, gloves, and do not inhale the fumes. Do not use any metal containers, measuring cups, stainless steel sinks, or tools with this mixture as this mixture will aggressively etch metal. Acid safety, think â€Å"triple A†, for Always Add the Acid, it’s whatever is in the container that will end up splashing. This etching solution, while made with common chemicals, should command respect. It is dangerous to you and surroundings treat it with respect. Put the board copper side up in the plastic container filled with etching solution. Use a soft plastic brush to gently wipe the board.You will notice the copper begin to dissolve. It takes about 3-4 minutes to get all the exposed copper dissolved. You just have to watch to make sure it is gone in all areas between the traces. Do not leave the board in the etching mix for too long as the traces will dissolve under the toner that is protecting them. [pic]  [pic] Use lac quer thinner (paint thinner and acetone do not work well) and a paper towel to remove any toner left on top of the copper traces. Tinning prevents the copper from oxidizing, which can make it hard to solder to in the future.If you choose, you can tin all the traces with solder and a soldering iron now. This actually makes drilling much easier because it helps to center the drill bit [pic] Print out the top side silkscreen layer on magazine paper and iron this onto the top side, using the same processes as above. Again, run under water and peel off the paper. Now you have the component ID’s on the top side. For layout design we use software: 1. P-Spice 2. ExpressPCBSetup 3. PCB Wizard 3. 50 Pro 4. EDWinXP Drill all the holes for the through-hole parts using the correct size PCB drill bit and rotary tool.Drill large mounting holes with a normal drill. PCB drill bits are carbide and made to drill through fiber glass that would quickly dull standard bits. There are a few very com mon sizes of bits and these are often sold in packs. We use . 0260? for IC holes and . 0310? for resistors and caps. [pic] CHAPTER 4 RESISTANCES [pic] INTRODUCTION A resistor is a two-terminal passive electronic component which implements electrical resistance as a circuit element. When a voltage V is applied across the terminals of a resistor, a current I will flow through the resistor in direct proportion to that voltage. The reciprocal of the onstant of proportionality is known as the resistance R, since, with a given voltage V, a larger value of R further â€Å"resists† the flow of current I as given by Ohm's law: [pic] UNITS The ohm (symbol: ? ) is the SI unit of electrical resistance. An ohm is equivalent to a volt per ampere. Since resistors are specified and manufactured over a very large range of values, the derived units of Milliohm (1 m? = 10? 3 ? ), Kilohm (1 k? = 103 ? ), Megohm (1 M? = 106 ? ) are also in common usage. Resistance is Determined partially by Compo sition,  and is inversely proportional to Cross Sectional Area. [pic]SERIES AND PARALLEL RESISTORS In a series configuration, the current through all of the resistors is the same, but the voltage across each resistor will be in proportion to its resistance. The potential difference (voltage) seen across the network is the sum of those voltages, thus the total resistance can be found as the sum of those resistances: [pic] [pic] As a special case, the resistance of N resistors connected in series, each of the same resistance R is given by NR. Resistors in a parallel configuration are each subject to the same potential difference (voltage), however the currents through them add.The conductance of the resistors then adds to determine the conductance of the network. Thus the equivalent resistance (Req) of the network can be computed: [pic] [pic] The parallel equivalent resistance can be represented in equations by two vertical lines â€Å"||† (as in geometry) as a simplified not ation. For the case of two resistors in parallel, this can be calculated using: [pic] As a special case, the resistance of N resistors connected in parallel, each of the same resistance R, is given by R/N.A resistor network that is a combination of parallel and series connections can be broken up into smaller parts that are either one or the other. For instance, [pic] [pic] POWER DISSIPATION The power P dissipated by a resistor (or the equivalent resistance of a resistor network) is calculated as: [pic] The first form is a restatement of Joule's first law. Using Ohm's law, the two other forms can be derived. The total amount of heat energy released over a period of time can be determined from the integral of the power over that period of time: [pic] Practical resistors are rated according to their maximum power dissipation.The vast majority of resistors used in electronic circuits absorbs much less than a watt of electrical power and require no attention to their power rating. Such resistors in their discrete form, including most of the packages detailed below, are typically rated as 1/10, 1/8, or 1/4 watt. Resistors required to dissipate substantial amounts of power, particularly used in power supplies, power conversion circuits, and power amplifiers, are generally referred to as power resistors; this designation is loosely applied to resistors with power ratings of 1 watt or greater.Power resistors are physically larger and tend not to use the preferred values, color codes, and external packages described below. If the average power dissipated by a resistor is more than its power rating, damage to the resistor may occur, permanently altering its resistance; this is distinct from the reversible change in resistance due to its temperature coefficient when it warms. Excessive power dissipation may raise the temperature of the resistor to a point where it can burn the circuit board or adjacent components, or even cause a fire. There are flameproof resistors that fail (open circuit) before they overheat dangerously.Note that the nominal power rating of a resistor is not the same as the power that it can safely dissipate in practical use. Air circulation and proximity to a circuit board, ambient temperature, and other factors can reduce acceptable dissipation significantly. Rated power dissipation may be given for an ambient temperature of 25  °C in free air. Inside an equipment case at 60  °C, rated dissipation will be significantly less; a resistor dissipating a bit less than the maximum figure given by the manufacturer may still be outside the safe operating area and may prematurely fail.TYPES OF RESISTER Fixed  resistors Variable resistors FIXED RESISTORS The diagram shows the construction of a carbon film resistor. During manufacture, a thin film of carbon is deposited onto a small ceramic rod. The resistive coating is spiraled away in an automatic machine until the resistance between the two ends of the rod is as close as possibl e to the correct value. Metal leads and end caps are added; the resistor is covered with an insulating coating and finally painted with colored bands to indicate the resistor value.Carbon film resistors are cheap and easily available, with values within  ±10% or  ±5% of their marked or ‘nominal' value. Metal film and metal oxide resistors are made in a similar way, but can be made more accurately to within  ±2% or  ±1% of their nominal value. There are some differences in performance between these resistor types, but none which affect their use in simple circuits. COLOUR CODING OF THE RESISTERS [pic] [pic] [pic] VARIABLE RESISTORS Variable resistors consist of a resistance track with connections at both ends and a wiper which moves along th track as you turn the spindle.The track may be made from carbon, cermets (ceramic and metal mixture) or a coil of wire (for low resistances). The track is usually rotary but straight track versions, usually called sliders, are also available. TYPE OF VARIABLE RESISTORS Linear (LIN) and Logarithmic (LOG) tracks Rheostat Potentiometer Presets LINEAR (LIN) AND LOGARITHMIC (LOG) TRACKS Linear (LIN) track means that the resistance changes at a constant rate as you move the wiper. Logarithmic (LOG) track means that the resistance changes slowly at one end of the track and rapidly at the other end, so halfway along the track is not half the total resistance!This arrangement is used for volume (loudness) controls because the human ear has a logarithmic response to loudness so fine control (slow change) is required at low volumes and coarser control (rapid change) at high volumes. It is important to connect the ends of the track the correct way round, if you find that turning the spindle increases the volume rapidly followed by little further change you should swap the connections to the ends of the track. RHEOSTAT This is the simplest way of using a variable resistor.Two terminals are used: one connected to an end of the track, the other to the moveable wiper. Turning the spindle changes the resistance between the two terminals from zero up to the maximum resistance. [pic] If the rheostat is mounted on a printed circuit board you may find that all three terminals are connected! However, one of them will be linked to the wiper terminal. This improves the mechanical strength of the mounting but it serves no function electrically. POTENTIOMETER Variable resistors used as potentiometers have all three terminals connected.These are miniature versions of the standard variable resistor. They are designed to be mounted directly onto the circuit board and adjusted only when the circuit is built. Presets are much cheaper than standard variable resistors so they are sometimes used in projects where a standard variable resistor would normally be used. [pic] PRESETS Multitier presets are used where very precise adjustments must be made. The screw must be turned many times (10+) to move the slider from one en d of the track to the other, giving very fine control. [pic] |[pic] |[pic] | |Preset |Presets |Multitier preset | |(open style) |(closed style) | | | | | | | | | |CHAPTER 5 CAPACITANCES [pic] INTRODUCTION |A capacitor is a passive electronic component that stores energy in the form of an electrostatic field. In its simplest form, a capacitor consists of two | |conducting plates separated by an insulating material called the dielectric. Capacitance is directly proportional to the surface areas of the plates, and is | |inversely proportional to the plates' separation. | |Capacitance also depends on the dielectric constant of the dielectric material separating the plates. | | |Capacitance calculated as XY x 10Z  for the numbers XYZ and the letter indicates the tolerance J, K or M for  ±5%,  ±10% and  ±20% respectively and unit is in pF. | |The standard units of Capacitance, | |farad: F   | |microfarad:  µF (1  µF = 10-6 F) |nanofarad: nF (1 nF = 10-9 F)   | |microfara d: pF (1 pF = 10-12 F) | | | | | | | |FOR CAPACITORS IN PARALLEL | |Capacitors in a parallel configuration each have the same applied voltage. Their capacitances add up.Charge is apportioned among them by size. Using the | |schematic diagram to visualize parallel plates, it is apparent that each capacitor contributes to the total surface area. | |[pic] | | | |FOR CAPACITORS IN SERIES | |Connected in series, the schematic diagram reveals that the separation distance, not the plate area, adds up.The capacitors each store instantaneous charge | |build-up equal to that of every other capacitor in the series. The total voltage difference from end to end is apportioned to each capacitor according to the | |inverse of its capacitance. The entire series acts as a capacitor  smaller  than any of its components. | |[pic] | |Capacitors are combined in series to achieve a higher working voltage, for example for smoothing a high voltage power supply. The voltage ratings, which are | |base d on plate separation, add up.In such an application, several series connections may in turn be connected in parallel, forming a matrix. The goal is to | |maximize the energy storage utility of each capacitor without overloading it. | |Series connection is also used to adapt  electrolytic capacitors  for AC use. | | | |CAPACITOR MAY BE: | |Polarized | |Unpolrized | |POLARIZED CAPACITOR(VALUE MAX THAN 1  µF) | pic] Circuit symbol:   Ã‚  [pic] ELECTROLYTIC CAPACITORS Electrolytic capacitors are polarized and  they must be connected the correct way round, at least one of their leads will be marked + or -. They are not damaged by heat when soldering. There are two designs of electrolytic capacitors;  axial  where the leads are attached to each end (220 µF in picture) and  radial  where both leads are at the same end (10 µF in picture). Radial capacitors tend to be a little smaller and they stand upright on the circuit board. It is easy to find the value of electr olytic capacitors because they are clearly printed with their capacitance and voltage rating.The voltage rating can be quite low (6V for example) and it should always be checked when selecting an electrolytic capacitor. If the project parts list does not specify a voltage, choose a capacitor with a rating which is greater than the project's power supply voltage. 25V is a sensible minimum for most battery circuits. TANTALUM BEAD CAPACITORS Tantalum bead capacitors are polarized and have low voltage ratings like electrolytic capacitors. They are expensive but very small, so they are used where a large capacitance is needed in a small size. Modern tantalum bead capacitors are printed with their capacitance, voltage and polarity in full.However older ones use a color-code system which has two stripes (for the two digits) and a spot of color for the number of zeros to give the value in  µF. The standard  colour code  is used, but for the spot,  grey  is used to mean ? 0. 01 and   white  means ? 0. 1 so that values of less than 10 µF can be shown. A third color stripe near the leads shows the voltage (yellow 6. 3V, black 10V, green 16V, blue 20V, grey 25V, white 30V, pink 35V). The positive (+) lead is to the right when the spot is facing you: ‘when the spot is in sight, the positive is to the right'.For example:   Ã‚  blue, grey, black spot  Ã‚   means 68 µF for example:   Ã‚  blue, grey, white spot  Ã‚   means 6. 8 µF For example:   Ã‚  blue, grey, grey spot  Ã‚   means 0. 68 µF UNPOLARIZED CAPACITOR(MAX. VALUE UPTO 1  µF) [pic] Circuit symbol:   Ã‚  [pic] Small value capacitors are Unpolrized and may be connected either way round. They are not damaged by heat when soldering, except for one unusual type (polystyrene). They have high voltage ratings of at least 50V, usually 250V or so. It can be difficult to find the values of these small capacitors because there are many types of them and several different labeling system s!Many small value capacitors have their value printed but without a multiplier, so you need to use experience to work out what the multiplier should be! For example  0. 1  means 0. 1 µF = 100nF. Sometimes the multiplier is used in place of the decimal point:   For example:   Ã‚  4n7  means 4. 7nF. POLYSTYRENE CAPACITORS This type is rarely used now. Their value (in pF) is normally printed without units. Polystyrene capacitors can be damaged by heat when soldering (it melts the polystyrene! ) so you should use a heat sink (such as a crocodile clip). Clip the heat sink to the lead between the capacitor and the joint. | | | | | | | VARIABLE CAPACITORS Variable capacitors are mostly used in radio tuning circuits and they are sometimes called ‘tuning capacitors'. They have very small capacitance values, typically between 100pF and 500pF (100pF  =  0. 0001 µF). The type illustrated usually has trimmers built in (for making small adjustments – see below) as well as the main variable capacitor. Many variable capacitors have very short spindles which are not suitable for the standard knobs used for variable resistors and rotary switches. It would be wise to check that a suitable knob is available before ordering a variable capacitor.Variable capacitors are  not  normally used in timing circuits because their capacitance is too small to be practical and the range of values available is very limited. Instead timing circuits use a fixed capacitor and a variable resistor if it is necessary to vary the time period. [pic][pic] Variable Capacitor Symbol Variable Capacitor | | | | | | | | TRIMMER CAPACITORS Trimmer capacitors (trimmers) are miniature variable capacitors.They are designed to be mounted directly onto the circuit board and adjusted only when the circuit is built. A small screwdriver or similar tool is required to adjust trimmers. The process of adjusting them requires patience because the presence of your hand and the tool wil l slightly change the capacitance of the circuit in the region of the trimmer! Trimmer capacitors are only available with very small capacitances, normally less than 100pF. It is impossible to reduce their capacitance to zero, so they are usually specified by their minimum and maximum values, for example 2-10pF.Trimmers are the capacitor equivalent of  presets  which are miniature variable resistors. [pic] [pic] Trimmer Capacitor Symbol Trimmer Capacitor CAPACITOR NUMBER CODE A number code is often used on small capacitors where printing is difficult: †¢ the 1st number is the 1st digit, †¢ the 2nd number is the 2nd digit, †¢ The 3rd number is the number of zeros to give the capacitance in pF. †¢ Ignore any letters – they just indicate tolerance and voltage rating.For example:   Ã‚  102  Ã‚  Ã‚  means 1000pF = 1nF   Ã‚  (not 102pF! ) For example:   Ã‚  472J  means 4700pF = 4. 7nF (J means 5% tolerance). |Color Code | |Color |Number | |Black | 0 | |Brown |1 | |Red |2 | |Orange |3 | |Yellow |4 | |Green |5 | |Blue |6 | |Violet |7 | |Grey |8 | |White |9 | CAPACITOR COLOR CODE A color code was used on polyester capacitors for many years. It is now obsolete, but of course there are many still around.The colors should be read like the resistor code, the top three color bands giving the value in pF. Ignore the 4th band (tolerance) and 5th band (voltage rating). For example: Brown, black, orange  Ã‚   means 10000pF = 10nF = 0. 01 µF. Note that there are no gaps between the colors bands, so 2 identical bands actually appear as a wide band. For example: Wide red, yellow  Ã‚   means 220nF = 0. 22 µF. CHAPTER 6 TRANSISTORS INTRODUCTION Transistors amplify current, A transistor may be used as a switch (either fully on with maximum current, or fully off with no current) and as an amplifier (always partly on).The amount of current amplification is called the current gain, symbol hFE. [pic] [pic] Transistor circuit symbols Types of transistor | | | | There are two types of standard transistors, NPN and PNP, with different circuit symbols. The letters refer to the layers of semiconductor material used to make the transistor. Most transistors used today are NPN because this is the easiest type to make from silicon. If you are new to electronics it is best to start by learning how to use NPN transistors. The leads are labeled base (B), collector (C) and emitter (E). These terms efer to the internal operation of a transistor but they are not much help in understanding how a transistor is used, so just treat them as labels. CONNECTING Transistors have three leads which must be connected the correct way round. Please take care with this because a wrongly connected transistor may be damaged instantly when you switch on. If you are lucky the orientation of the transistor will be clear from the PCB or strip board layout diagram, otherwise you will need to refer to a supplier's catalogue to identify the leads. The dr awings on the right show the leads for some of the most common case styles.Please note that transistor lead diagrams show the view from below with the leads towards you. This is the opposite of IC (chip) pin diagrams which show the view from above. [pic] TRANSISTOR CODES There are three main series of transistor codes used in the UK: ? Codes beginning with B (or A), for example BC108, BC478 the first letter B is for silicon, A is for germanium (rarely used now). The second letter indicates the type; for example C means low power audio frequency; D means high power audio frequency; F means low power high frequency. The rest of the code identifies the particular transistor.There is no obvious logic to the numbering system. Sometimes a letter is added to the end (e. g. BC108C) to identify a special version of the main type, for example a higher current gain or a different case style. If a project specifies a higher gain version (BC108C) it must be used, but if the general code is given (BC108) any transistor with that code is suitable. ? Codes beginning with TIP, for example TIP31A TIP refers to the manufacturer: Texas Instruments Power transistor. The letter at the end identifies versions with different voltage ratings. ? Codes beginning with 2N, for example 2N3053The initial ‘2N' identifies the part as a transistor and the rest of the code identifies the particular transistor. There is no obvious logic to the numbering system. CHOOSING A TRANSISTOR Most projects will specify a particular transistor, but if necessary you can usually substitute an equivalent transistor from the wide range available. The most important properties to look for are the maximum collector current IC and the current gain hFE. To make selection easier most suppliers group their transistors in categories determined either by their typical use or maximum power rating. NPN transistors | |Code | |PNP transistors | |Code |Structure | |Case  style |There is a diagram showing the lead s for some of the most common case styles in the Connecting section above.This information | | |is also available in suppliers' catalogues. | |IC max. |Maximum collector current. | |VCE max. |Maximum voltage across the collector-emitter junction. | | |You can ignore this rating in low voltage circuits. | |hFE |This is the current gain (strictly the DC current gain). The guaranteed minimum value is given because the actual value varies | | |from transistor to transistor – even for those of the same type! Note that current gain is just a number so it has no units. | | The gain is often quoted at a particular collector current IC which is usually in the middle of the transistor's range, for | | |example ‘[email  protected]' means the gain is at least 100 at 20mA. Sometimes minimum and maximum values are given. Since the gain is | | |roughly constant for various currents but it varies from transistor to transistor this detail is only really of interest to | | |experts. | | | | | |Why hFE? | |It is one of a whole series of parameters for transistors, each with their own symbol. There are too many to explain here. | |Ptot max. |Maximum total power which can be developed in the transistor, note that a heat  sink will be required to achieve the maximum | | |rating. This rating is important for transistors operating as amplifiers; the power is roughly IC ? VCE. For transistors | | |operating as switches the maximum collector current (IC max. is more important. | |Category |This shows the typical use for the transistor, it is a good starting point when looking for a substitute. Catalogues may have | | |separate tables for different categories. | |Possible  substitutes |These are transistors with similar electrical properties which will be suitable substitutes in most circuits. However, they may | | |have a different case style so you will need to take care when placing them on the circuit board. | THE NPN TRANSISTORIn the previous tutorial we saw tha t the standard Bipolar Transistor or BJT comes in two basic forms. An NPN (Negative-Positive-Negative) type and a PNP (Positive-Negative-Positive) type, with the most commonly used transistor type being the NPN Transistor. We also learnt that the transistor junctions can be biased in one of three different ways – Common Base, Common Emitter and Common Collector. In this tutorial we will look more closely at the â€Å"Common Emitter† configuration using NPN Transistors with an example of the construction of a NPN transistor along with the transistors current flow characteristics is given below. pic] THE COMMON EMITTER CONFIGURATION As well as being used as a semiconductor switch to turn load currents â€Å"ON† or â€Å"OFF† by controlling the Base signal to the transistor in ether its saturation or cut-off regions, NPN Transistors can also be used in its active region to produce a circuit which will amplify any small AC signal applied to its Base terminal with the Emitter grounded. If a suitable DC â€Å"biasing† voltage is firstly applied to the transistors Base terminal thus allowing it to always operate within its linear active region, an inverting amplifier circuit called a single stage common emitter amplifier is produced.One such Common Emitter Amplifier configuration of an NPN transistor is called a Class A Amplifier. A â€Å"Class an Amplifier† operation is one where the transistors Base terminal is biased in such a way as to forward bias the Base-emitter junction. The result is that the transistor is always operating halfway between its cut-off and saturation regions, thereby allowing the transistor amplifier to accurately reproduce the positive and negative halves of any AC input signal superimposed upon this DC biasing voltage. Without this â€Å"Bias Voltage† only one half of the input waveform would be amplified.This common emitter amplifier configuration using an NPN transistor has many applications but is commonly used in audio circuits such as pre-amplifier and power amplifier stages. With reference to the common emitter configuration shown below, a family of curves known as the Output Characteristics Curves relates the output collector current, (Ic) to the collector voltage, (Vce) when different values of Base current, (Ib) are applied to the transistor for transistors with the same ? value. A DC â€Å"Load Line† can also be drawn onto the output characteristics curves to show all the possible operating points when ifferent values of base current are applied. It is necessary to set the initial value of Vce correctly to allow the output voltage to vary both up and down when amplifying AC input signals and this is called setting the operating point or Quiescent Point, Q-point for short and this is shown below. SINGLE STAGE COMMON EMITTER AMPLIFIER CIRCUIT |[pic] | CHAPTER 7 CONDENSER MIC [pic] INTRODUCTION Microphones are a type of  transducer  Ã¢â‚¬â€œ a device w hich converts energy from one form to another.Microphones convert acoustical energy (sound waves) into electrical energy (the audio signal). Different types of microphone have different ways of converting energy but they all share one thing in common: The  diaphragm. This is a thin piece of material (such as paper, plastic or aluminum) which vibrates when it is struck by sound waves. In a typical hand-held mic like the one below, the diaphragm is located in the head of the microphone. LOCATION OF MICROPHONE DIAPHRAGM [pic] When the diaphragm vibrates, it causes other components in the microphone to vibrate.These vibrations are converted into an electrical current which becomes the audio signal. Note: At the other end of the audio chain, the loudspeaker is also a transducer – it converts the electrical energy back into acoustical energy. TYPES OF MICROPHONE There are a number of different types of microphone in common use. The differences can be divided into two areas: (a) T HE TYPE OF CONVERSION TECHNOLOGY THEY USE this refers to the technical method the mic uses to convert sound into electricity. The most common technologies are dynamic, condenser, ribbon and crystal.Each has advantages and disadvantages, and each is generally more suited to certain types of application. The following pages will provide details. (b) THE TYPE OF APPLICATION THEY ARE DESIGNED FOR some mics are designed for general use and can be used effectively in many different situations. Others are very specialized and are only really useful for their intended purpose. Characteristics to look for include directional properties, frequency response and impedance (more on these later). MIC LEVEL & LINE LEVEL The electrical current generated by a microphone is very small.Referred to as mic level, this signal is typically measured in mill volts. Before it can be used for anything serious the signal needs to be amplified, usually to line level (typically 0. 5 -2V). Being a stronger and mo re robust signal, line level is the standard signal strength used by audio processing equipment and common domestic equipment such as CD players, tape machines, VCRs, etc. This amplification is achieved in one or more of the following ways: †¢ Some microphones have tiny built-in amplifiers which boost the signal to a high mic level or line level. The mic can be fed through a small boosting amplifier, often called a line amp. †¢ Sound mixers have small amplifiers in each channel. Attenuators can accommodate mics of varying levels and adjust them all to an even line level. †¢ The audio signal is fed to a power amplifier – a specialized amp which boosts the signal enough to be fed to loudspeakers. Audio signal is fed to a power amplifier – a specialized amp which boosts the signal enough to be fed to loudspeakers. CONDENSER MICROPHONES Condenser  means  capacitor, an electronic component which stores energy in the form of an electrostatic field.The term condenser  is actually obsolete but has stuck as the name for this type of microphone, which uses a capacitor to convert acoustical energy into electrical energy. Condenser microphones require power from a battery or external source. The resulting audio signal is stronger signal than that from a dynamic. Condensers also tend to be more sensitive and responsive than dynamics, making them well-suited to capturing subtle nuances in a sound. They are not ideal for high-volume work, as their sensitivity makes them prone to distort. HOW CONDENSER MICROPHONES WORK A capacitor has two plates with a voltage between them.In the condenser mic, one of these plates is made of very light material and acts as the diaphragm. The diaphragm vibrates when struck by sound waves, changing the distance between the two plates and therefore changing the capacitance. Specifically, when the plates are closer together, capacitance increases and a charge current occurs. When the plates are further apart, ca pacitance decreases and a discharge current occurs. A voltage is required across the capacitor for this to work. This voltage is supplied either by a battery in the mic or by external phantom power.Phantom power is a means of distributing a DC current through audio cables to provide power for microphones and other equipment. The supplied voltage is usually between 12 and 48 Volts, with 48V being the most common. Individual microphones draw as much current from this voltage as they need. [pic] THE ELECTRET CONDENSER MICROPHONE The Electret condenser mic uses a special type of capacitor which has a permanent voltage built in during manufacture. This is somewhat like a permanent magnet, in that it doesn't require any external power for operation.However good Electret condensers mics usually include a pre-amplifier which does still require power. Other than this difference, you can think of an Electret condenser microphone as being the same as a normal condenser. Technical Notes: †¢ Condenser microphones have a flatter frequency response than dynamics. A condenser mic works in much the same way as an electrostatic tweeter (although obviously in reverse) DIRECTIONAL PROPERTIES Every microphone has a property known as  directionality. This describes the microphone's sensitivity to sound from various directions.Some microphones pick up sound equally from all directions; others pick up sound only from one direction or a particular combination of directions. The types of directionality are divided into three main categories: 1. OMNI DIRECTIONAL Picks up sound evenly from all directions (Omni means â€Å"all† or â€Å"every†). 2. UNIDIRECTIONAL Picks up sound predominantly from one direction. 3. BIDIRECTIONAL picks up sound from two opposite directions. CHAPTER 8 IC LM386N [pic] INTRODUCTION The LM386 is a power amplifier designed for use in low voltage consumer applications.The gain is internally set to 20 to keep external part count low, but the a ddition of an external resistor and capacitor between pins 1 and 8 will increase the gain to any value from 20 to 200. The inputs are ground referenced while the output automatically biases to one-half the supply voltage. The quiescent power drain is only 24 mill watts when operating from a 6 volt supply, making the LM386 ideal for battery operation. FEATURES Battery operation Minimum external parts Wide supply voltage range: 4V–12V or 5V–18V Low quiescent current drain: 4mA Voltage gains from 20 to 200Ground referenced input Self-centering output quiescent voltage Low distortion: 0. 2% (AV = 20, VS = 6V, RL = 8W, PO =125mW, f = 1 kHz) Available in 8 pin MSOP package APPLICATION HINTS GAIN CONTROL To make the LM386 a more versatile amplifier, two pins (1 and 8) are provided for gain control. With pins 1 and 8 open the 1. 35 k? resistor sets the gain at 20 (26 dB). If a capacitor is put from pin 1 to 8, bypassing the 1. 35 k? resistor, the gain will go up to 200 (46 dB) . If a resistor is placed in series with the capacitor, the gain can be set to any value from 20 to 200.Gain control can also be done by capacitive coupling a resistor (or FET) from pin 1 to ground. Additional external components can be placed in parallel with the internal feedback resistors to tailor the gain and frequency response for individual applications. For example, we can compensate poor speaker bass response by frequency shaping the feedback path. This is done with a series RC from pin 1 to 5 (paralleling the internal 15 k? resistor). For 6 dB effective bass boost: R. 15 k? , the lowest value for good stable operation is R = 10 k? if pin 8 is open. If pins 1 and 8 are bypassed then R as low as 2 k? an be used. This restriction is because the amplifier is only compensated for closed-loop gains greater than 9. INPUT BIASING The schematic shows that both inputs are biased to ground with a 50 kW resistor. The base current of the input transistors is about 250 nA, so the inputs are at about 12. 5 mV when left open. If the dc source resistance driving the LM386 is higher than 250 kW it will contribute very little additional offset (about 2. 5 mV at the input, 50 mV at the output). If the dc source resistance is less than 10 kW, then shorting the unused input to ground will keep the offset low (about 2. mV At the input, 50 mV at the output). For dc source resistances between these values we can eliminate excess offset by putting a resistor from the unused input to ground, equal in value to the dc source resistance. Of course all offset problems are eliminated if the input is capacitive coupled. When using the LM386 with higher gains (bypassing the 1. 35 kW resistors between pins 1 and 8) it is necessary to bypass the unused input, preventing degradation of gain and possible instabilities. This is done with a 0. 1 ? F capacitor or a short to ground depending on the dc source resistance on the driven input.CHAPTER 9 EARPHONE [pic] INTRODUCTION Headphones are a pair of small loudspeakers, or less commonly a single speaker, held close to a user's ears and connected to a signal source such as an audio amplifier, radio, CD player or portable media player. They are also known as stereophones, headsets or, colloquially cans. The in-ear versions are known as earphones or earbuds. In the context of telecommunication, the term headset is used to describe a combination of headphone and microphone used for two-way communication, for example with a telephone.The telephone earpiece such as the one pictured at the right was common at the beginning of the 20th century. Headphones originated from the earpiece, and were the only way to listen to audio signals before amplifiers were developed. The first truly successful set was developed by Nathaniel Baldwin, who made them by hand in his kitchen and sold them to the U. S. Navy. Very sensitive headphones such as those manufactured by Brandes around 1919 were commonly used for early radio work. These early headphones used moving iron drivers, either single ended or balanced armature.The requirement for high sensitivity meant no damping was used, thus the sound quality was crude. They also had very poor comfort compared to modern types, usually having no padding and too often having excessive clamping force to the head. Their impedance varied; headphones used in telegraph and telephone work had an impedance of 75 ohms. Those used with early wireless radio had to be more sensitive and were made with more turns of finer wire; impedance of 1,000 to 2,000 ohms was common, which suited both crystal sets and triode receivers.In early powered radios, the headphone was part of the vacuum tube's plate circuit and had dangerous voltages on it. It was normally connected directly to the positive high voltage battery terminal, and the other battery terminal was securely earthed. The use of bare electrical connections meant that users could be shocked if they touched the bare headphone connections while adjusting an uncomfortable headset. APPLICATIONS Headphones may be used both with fixed equipment such as CD or DVD players, home theater, personal computers and with portable devices (e. g. igital audio player/mp3 player, mobile phone, etc. ). Cordless headphones are not connected via a wire, receiving a radio or infrared signal encoded using a radio or infrared transmission link, like FM, Bluetooth or Wi-Fi. These are actually made of powered receiver systems of which the headphone is only a component, these types of cordless headphones are being used more frequently with events such as a Silent disco or Silent Gig. In the professional audio sector headphones are used in live situations by disc jockeys with a DJ mixer and sound engineers for monitoring signal sources.In radio studios, DJs use a pair of headphones when talking to the microphone while the speakers are turned off, to eliminate acoustic feedback and monitor their own voice. In studio recordings, musicians and si ngers use headphones to play along to a backing track. In the military, audio signals of many varieties are monitored using headphones. Wired headphones are attached to an audio source. The most common connection standards are 6. 35mm ( ) and 3. 5mm TRS connectors and sockets. The larger 6. 35mm connector tending to be found on fixed location home or professional equipment.Sony introduced the smaller, and now widely used, 3. 5mm â€Å"minijack† stereo connector in 1979, adapting the older monophonic 3. 5mm connector for use with its Walkman portable stereo tape player and the 3. 5mm connector remains the common connector for portable application today. Adapters are available for converting between 6. 35mm and 3. 5mm devices. BENEFITS AND LIMITATIONS [pic] Headphones may be used to prevent other people from hearing the sound either for privacy or to prevent disturbance, as in listening in a public library.They can also provide a level of sound fidelity greater than loudspeaker s of similar cost. Part of their ability to do so comes from the lack of any need to perform room correction treatments with headphones. High quality headphones can have an extremely flat low-frequency response down to 20  Hz within 3dB. However, rated frequency response distortion figures do not provide information on what character the sound reproduced at that frequency will be. Marketed claims such as ‘frequency response 4  Hz to 20  kHz' are usually overstatements; the product's response at frequencies lower than 20  Hz is typically very small.Headphones are also useful for video games that use 3D positional audio processing algorithms, as they allow players to better judge the position of an off-screen sound source (such as the footsteps of an opponent). Although modern headphones have been particularly widely sold and used for listening to stereo recordings since the release of the Walkman, there is subjective debate regarding the nature of their reproduction of stereo sound. Stereo recordings represent the position of horizontal depth cues (stereo separation) via volume differences of the sound in question between the two channels.When the sounds from two speakers mix, they create the phase difference the brain uses to locate direction. Through most headphones, because the right and left channels do not combine in this manner, the illusion of the phantom center can be perceived as lost. Hard panned sounds will also only be heard only in one ear rather than from one side. This latter point is of particular importance for earlier stereo recordings which were less sophisticated, sometimes playing vocals through one channel and music through the other.Binaural recordings use a different microphone technique to encode direction directly as phase, with very little amplitude difference (except above 2  kHz) often using a dummy head, and can produce a surprisingly life-like spatial impression through headphones. Commercial recordings almost alwa ys use stereo recording, because historically loudspeaker listening has been more popular than headphone listening. It is possible to change the spatial effects of stereo sound on headphones to better approximate the presentation of speaker reproduction by using frequency-dependent cross-feed between the channels, or—better still—aBlumlein shuffler (a custom EQ employed to augment the low-frequency content of the difference information in a stereo signal). While cross-feed can reduce the unpleasantness that some listeners find with hard panned stereo in headphones, the use of a dummy head during recording, with artificial pinnae, can allow on playback through headphones, the experience of hearing the performance as though situated in the position of the dummy head. Optimal sound is achieved when the dummy head matches the listener's head, since pinnae vary greatly in size and shape.Headsets can have ergonomic benefits over traditional telephone handsets. They allow cal l center agents to maintain better posture instead of tilting their head sideways to cradle a handset. Over time, headphone cables fail. The common scenario in which a replacement might need to be purchased is the physical breakdown of copper wiring at junction points on the cord (at the TRS jack, or at the point of connection to the headphone). These are the sites of greatest and most stressful motion on a cord and so they are typically fitted with some kind of strain relief.CHAPTER 10 APPLICATIONS,FUTURE SCOPE AND CONCLUSION APPLICATIONS IN SPY AGENCIES [pic] 1. To hear private conversations of anyone. 2. To caught anyone doing any illegal work. SOUND AMPLIFIER 1. To amplify the low power audio signals. 2. In hearing aids. SOME OTHER APPLICATIONS As a spy can be use in 1. Concert halls 2. Court houses 3. Conference rooms 4. Embassies 5. Government facilities 6. Recording studios. 7. In army. 8. Secret agencies. FUTURE SCOPE [pic]Spy ears are widely using in the spy agencies due to its amplifying capability of the low power audio signals into the high power audible audio signals due to this property of spy ears we can use it to hear the private conversations of anyone, In the present time spy ears are very popular to hear the private conversations and it can also be used as a hearing aid for the persons who do not have the ability to hear the voice correctly. Spy ears amplifies the sound so it amplify the sounds of low signal for the person and he can clearly hear the voice of the other person and other things.If we consider the future prospectus than we can imagine that spy ears will become very popular in the future due to its hiding capability because we all know that at what rate corruption and illegal things are increasing so due to help of this equipment we can hear the conversation of any suspicious person and stop him. Spy ear can easily hide so they are very difficult to find and the other person can not see it and we can easily hear the conversation of the peritcular person and he van not imagine than someone hearing his conversation and his secret is now opened.TYPES OF SPY EAR In the present condition spy ear are of two types: 1. Wired. 2. Wireless. 1. WIRED [pic] ? Wired spy ear for the short distance use only. ? We can only hear the sound of the person who is near the spy ear. ? Due to its short distance use they are now uses very less in compare to wireless spy ears. ? Wired spy ear can be used to hear the voice of the person at bus stop, school, colleges and many other places without getting his/her attention towards us. ? Wired spy ear can also be used as a hearing aid because of its audio amplifying capability.But if we see in present condition the use of wired spy ears is very less because wireless spy ears can cover a wide range than the wired spy ears, many spy agencies and private security forces use wireless spy ear for the long distance communication. 2. WIRELESS [pic] ? Wire less spy ears are widely using for th e long distance conversation due to its capability of receiving and sending signals from the long distance. ? Wire less spy ears are widely using in spy agencies and private security agencies to connect an long distance communication. ? Wire less spy ear consist of a receiving and a transmitting device. Both device are fabricated on the separate board so they have the property of long distance connectivity and the voice quality is also good. ? Wire less spy ears are also using with the mobile equipments. Transmitting device contain a sim and from our we call on it and after the connectivity we can hear and transmit our voice without getting the attention of the other person. CONCLUSION By the above all discussion at last we can say that the spy ear is very helpful at many levels such as PRIVATE LEVEL †¢ We can hear the conversation of our neighbours without getting their attention. We can hear the conversation of people at bus stop, school, colleges without looking towards them †¢ We can use it as h sound amplifier for low voice signals etc. COUNTRY LEVEL †¢ We can use spy ear to hear the conversation of any suspected person and can know that what is going on. †¢ We can use it against any corrupted person and send him in the jail. At last we can say that the spy ears are very helpful for private as well as national security purpose and in future they will become more popular due to there ability of hiding and catching low frequency voice signal. ———————– IASSCOM FORTUNE INSTITUTE OF TECHNOLOGY 1