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Get together in your Project groups. Projects: Project Proposal . Make sure that you read pages P4 and P5 of your lab manual. Make sure that your group comes to final agreement on the project and that you consult the tutors. Work out in detail what equipment you will need. .
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Get together in your Project groups. Projects: Project Proposal • Make sure that you read pages P4 and P5 of your lab manual. • Make sure that your group comes to final agreement on the project and that you consult the tutors. • Work out in detail what equipment you will need. • Write a one page (i.e., quite detailed and specific) description of the project. • Develop a project timeline: who does what and when.
Fill in and hand in the final proposal. • We will mark your proposals and hand them back to you next week. Projects: Project proposal #2 • Please give the complete details of all students in your Project Group. Marks will only be awarded to members of the team who have signed the forms. • You must clearly indicate your project group number, • e.g., 10ADV A, B, C or D --- check your initial proposal
ADV 4: High and Low Pass Filters Introductory mini-lecture
Generalised Ohm’s Law • Impedance defined by ratio Z = v/i • Z = R + jX, where R is the resistance and X is the reactance: • R is constant • X depends on frequency • Ohmic materials: Z independent of i • Ohm’s Law for AC Circuits:v = Zi
Series impedances • Series: current flows through one component and then the other • Voltage drop across two components in series: Vtotal = I(Z1+Z2) • Currents through the two components are equal by Kirchhoff’s junction law
Parallel impedances • Current divides in inverse proportion to the impedance, i.e., the smaller impedance carries the greater current. • Voltage drop across two components in parallel are equal by Kirchhoff’s loop law
AC voltage dividers • An AC voltage divider produces an output voltage vout that is a proportion of the input voltage vin • |vout/vin| is set by the relative magnitudes of Z1 and Z2 , i.e.,
Phase angle between vin and i • Input voltage vin is the vector sum of vR = Ri and vC=(-j/ωC)i … but |vin| remains constant • At low frequency, |vC|>>|vR| (θ→90°); at high frequency, |vC|<<|vR| (θ→0°) • Crossover or corner frequency occurs when |vC|=|vR|