Problem 01: An RF engineer needs to use a Butterworth filter to pass an audio signal based on its application. Design the required second-stage Butterworth filter to pass the output signal based on cut-off frequency to avoid the noisy signal with proper labelling, calculation, and explanation. Consider cut-off frequency fc = 55 kHz, quality factor, Q = 5 and capacitance, C = 0.030 µF for the filter. Show the frequency response curve of the constructed filter. Also draw the circuit. The criteria for cut-off frequency, fc, is provided below according to your ID: 5 0 or 2 or 4 or 6 or 8 1 or 3 or 5 or 7 or 9 Pass output signal Before fc After fc [10]

filter specification a. What kind of filter is this? b. What is the transition band of the filter is given as ₂ = 0.4, , = 0.5, ₁ = 0.01, &₂ = 0.00001, c. Draw the absolute specification d. What is the specification in relative? e. Draw the relative specification. f. If the filter is applied on a signal sampled at 100 kHz, what are the frequency edges in Hz?

What is a bandpass filter? How is its bandwidth defined?

Design an ACTIVE band-pass filter for the midrange part of a loudspeaker so that the bandpass region is 400 Hz-2000 Hz (as defined by the -3dB points). Design the circuit so that the absolute gain is 2. a. Draw the circuit diagram and specify the resistor and capacitor values. Assume you can use either 100, 330, 500, or 1000 Ohm resistors and can select any value of capacitor. b. Sketch the frequency response (Gain [dB] vs. frequency (Hz)). Note that you will need to convert your gain to dB before plotting. Magnitude (dB) 15 10 5 midrange 12 1 -5 -10 -15 -20 -25 10 100 1,000 Frequency (Hz) 10,000 100,000