Sehir - EE 312 - Fall 2017 Introduction to Communication Systems Lab 1 manual Basic Lab Instruments Prepared by: Ilkin Safarli Supervisor: Dr. Kemal Ozdemir • Preliminary work is due just before the lab and Final Report is due a week after the lab session. • Preliminary and Final reports are all to be performed individually. Sehir - EE 312 1 Lab 1 - Page 2 of 5 October, 2017 Objective The focus of Lab 1 is to get familiar with digital multimeter, function generator, and oscilloscope. We will construct simple electronic circuits and analyze the behavior of these circuits by using the basic equipment listed above. 2 Preliminary Work All answers must be clear and straight to the point (concise). You are required to explain your answers in your own words. Plagiarism will lead to point deduction. Before the lab do research on the followings: (a) What is the operating principle of voltmeters and ammeters? (b) What is the function of function generator? (c) What are the functions of oscilloscope and multimeter? How are multimeters different from oscilloscopes? Before the lab complete the following tasks: (d) Build the circuit in Figure 2 by using Cadence1 and run simulation (transient response for 5 ms). Attach screenshot of your circuit. 2 (e) Plot Out 1 and Out 2 in Figure 2 by using Cadence. Attach the figures to preliminary work. 1 You can use any circuit simulator such a Cadence, Multisim, Partsim, etc. This simulator can be used online, and is free and simple to use, but requires registration: https://easyeda.com 2 If you are unfamiliar with circuit simulation, you are required to use one of the numerous online resources to learn the basic circuit simulation techniques. There are a number of videos on using EasyEDA on Youtube. Sehir - EE 312 3 3.1 Lab 1 - Page 3 of 5 October, 2017 Procedure and Analysis Digital Multimeter Digital Multimeter can measure voltage, current, and resistance. Remember that voltage measurements are taken in parallel while current measurements are taken in series. 3.1.1 Exercise: measuring voltage and current Build the circuit in Figure 1. Measure the voltage across R1 and current through R2. Calculate the theoretical values and in your report compare them with the measured values. Figure 1: Resistive Network 3.2 Function Generator The function generator generates sine waves, square waves and triangular waves. The waveform parameters such as duty cycle, frequency, and amplitude (peak-topeak) are set via the front panel buttons. 3.2.1 Exercise: setting parameters Set the frequency to 5 KHz, waveform to square wave and amplitude to a random value. Attach the output to the scope probes of oscilloscope. 3.3 Oscilloscope Oscilloscopes are used to observe the change of an electrical signal over time. The observed waveform can be analyzed for such properties as amplitude, frequency, rise time, time interval, distortion and others3. Modern oscilloscopes can also do simple math operations such as invert, add, subtract and FFT. Sehir - EE 312 3.3.1 Lab 1 - Page 4 of 5 October, 2017 Multimeter vs Oscilloscope We typically use multimeter for DC operations, while oscilloscope is used for time varying signals. Digital multimeters can do very limited AC measurements (i.e. AC and frequency) and its frequency range is very limited. On the other hand oscilloscope cannot do much DC analysis. In short DMM is best for DC measurement and oscilloscope for AC analysis. 3.3.2 Exercise: measuring via oscilloscope Most properties of a signal can be measured by using the measure function of oscilloscope. In previous exercise we attached the output of function generator to scope of oscilloscope. Now press Measure button of oscilloscope and measure frequency and amplitude of the signal. Take screenshots and attach them to your report. Note: in order to take screenshots insert a USB flash drive into the front USB flash port of oscilloscope and use Save/Recall button, or use the camera on your mobile device to capture a clear image of the oscilloscope screen. Another way of measuring signal properties is to use cursors. By using cursors measure amplitude and frequency again, take screenshots and attach them to your report. 3Retrieved 3.4 from https://en.wikipedia.org/?title=Oscilloscope Sine Wave Converter Build the circuit in Figure 2 (for both op-amps: VS+ = 10 V, VS− = 10 V). − Connect the scope probes to Out 1. What is shape of the signal? Measure amplitude and frequency of the signal. Attach screenshots to your report. Repeat the same steps for Out 2. Give a few examples for real life use-case of this circuit. Figure 2: sine wave converter In your report compare simulation results with the results that you obtained in lab and comment. Sehir - EE 312 4 Lab 1 - Page 5 of 5 October, 2017 Report Format Your post lab report should consist of a just Results & Discussions. Answer ALL the questions posed to you in section 3 of this manual for the discussion part, and include all the simulation results (where you have been asked to compare results) and the screenshots (oscilloscope measurements) from the lab experiment for the results part. You should organize your results and discussions into subsections titled with the experiment number (such as 3.1.1).