1. **Problem Statement:** (a)(i) Distinguish between modulation and demodulation in electronics and instrumentation. (a)(ii) Give 4 applications of modulation and demodulation in radio receivers. (b)(i) Describe the working principle of an oscilloscope as a measuring instrument with the aid of a diagram. 2. **Modulation vs Demodulation:** - **Modulation** is the process of varying a carrier signal in order to transmit information. It involves altering the amplitude, frequency, or phase of the carrier wave based on the information signal. - **Demodulation** is the reverse process where the original information signal is extracted from the modulated carrier wave at the receiver. 3. **Applications of Modulation and Demodulation in Radio Receivers:** - To allow transmission of signals over long distances by shifting the frequency to a higher carrier frequency. - To enable multiple signals to share the same channel via frequency division multiplexing. - To improve signal quality and reduce noise and interference. - To facilitate the reception of signals by tuning to specific carrier frequencies. 4. **Working Principle of an Oscilloscope:** - An oscilloscope is an electronic instrument used to display and analyze the waveform of electronic signals. - It works by applying the input signal to the vertical deflection plates of a cathode ray tube (CRT) or a digital display. - A time base generator produces a sawtooth voltage that deflects the electron beam horizontally at a constant rate. - The vertical deflection corresponds to the instantaneous voltage of the input signal. - The resulting trace on the screen represents voltage versus time, allowing measurement of amplitude, frequency, and waveform shape. 5. **Summary:** - Modulation encodes information onto a carrier wave; demodulation retrieves it. - Applications include long-distance communication, multiplexing, noise reduction, and selective reception. - Oscilloscopes visualize electrical signals by converting voltage variations into a visible trace over time. \[\text{No diagram included as per text-only response requirements}\]