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Q2 (a) As part of a radio receiver, you are asked to design a simple bandpass filter using a series inductor, capacitor and resistor. The filter needs to pass a centre frequency of fo= 1089 kHz with a bandwidth of 9 kHz. Do this by finding the capacitor and resistor values together with a 240 µH inductor that will give you the correct centre frequency and bandwidth. Also, calculate the quality factor Q for your filter. Sketch the filter circuit and show all your calculations. [8 marks] (b) In practice, multiple radio channels are broadcast at different frequencies and radio receivers use tuneable bandpass filters to select a single channel. The band pass filters alter, or tune, their centre frequency to select the required channel. (i) Suggest how your bandpass filter circuit might be modified to allow it to tune to different frequencies. After the radio signal has been received it occupies frequencies between 0-9 kHz. Showing your calculations, design a low pass filter to pass this signal. The cut off frequency should be at 9.5 kHz. Sketch the filter circuit. [7 marks] (ii)