Sound Monitoring System

Members : Qinglie Zhu, Zheng Zhao, Junhao Zhu, Zhiyuan Zhang Advisor: Valerio Selis General Ideas: In this week, the group succeeded in constructing the entire circuit consisting of amplifier circuit and ADC circuit. Furthermore, the algorithm of the sound monitoring system has been optimized as well. Next, in order to protect the circuit from damaging, the circuit was packaged. Finally, the design of poster is finished in this week. Experience of the Experiment: 1.     Reconstruct the sound monitoring system For the purpose of stability and beauty, the circuit was reconstructed in the lab. Differentiating from the previous circuit, the length of wires and pins were cut so that the components can be fixed in the breadboard. The entire circuit is shown as Figure 1 below.  Figure 1. The Entire Circuit 2.     The Optimization of Algorithm As for the algorithm part, the original one was optimized in this week. In detailed, the first part that needed to be

Members: Qinglie Zhu, Zheng Zhao, Junhao Zhu, Zhiyuan Zhang Advisor: Valerio Selis General Ideas: In last week, the biggest problem we countered was that the voltage gain of the amplifier circuit was not high enough, which was only 30. Consequently, the sound signal cannot be displayed normally on the oscilloscope and therefore the arduino could not read the correct analog value. In this week, our most important task is to think about a method to increase the gain. Additionally, we planned to connect the buzzer to the arduino and compile the code so that if the sound level transcends the threshold, the sound monitor system will warn the user. Experiment: 1. Increase the gain of the amplifier circuit We came up with two methods to increase the gain of the amplifier. Firstly, according to the research, the gain of LM386 amplifier can be set from 20 to 200 using a resistor and a capacitor across pin1 and pin8.  Figure1: The configuration of LM386 However, af