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Measurement of passive frequency crossovers for loudspeaker systems
Holínský, Jan ; Hanák, Pavel (referee) ; Balík, Miroslav (advisor)
The content of the master´s thesis is to approach the issue of measuring the characteristics of passive frequency crossover. The work describes individual types of measured characteristics and their possibility of measurement. Then the work describes design of modules for measurement characteristics of passive frequency crossover (shunt, resistive load and amplifier). These modules were made and tested for its functions. For the amplifier is then made a second design for fulfilment requirements. The second version isn’t made in this work. At the end of the work was prepared the theoretical part of the laboratory task: Measurement of characteristics of passive frequency crossover, including protocol.
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Loudspeaker Box with Variable Crossover Frequency
Tomášek, Martin ; Balík, Miroslav (referee) ; Schimmel, Jiří (advisor)
This bachelor´s thesis deals with middle-sized loudspeaker system in D´Appolito configuration. The aim of this thesis is to design and to realize the loudspeaker system, which includes selection of suitable loudspeakers and their position in designed baffle including design of variable crossover frequency. The text is divided into a few sections, where are the points of this project described. In the first half there are briefly described basic principles of loudspeakers and design loudspeaker systems, especially 2-way loudspeakers, and specific properties of D´Appolito configuration. Then there are described principles of frequency crossovers used in loudspeaker systems and what is expected for their construction. In the second half, there is described realization of baffle itself and variable frequency crossover. Because this thesis concurs to semestral thesis, there is also a chapter about simulation. In the end there are diagrammatized the measured data of frequency and dispersion characteristics and a few dispersion characteristics for different crossing frequences.
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Laboratory device focused on the switched capacitor circuits
Urban, Lukáš ; Šotner, Roman (referee) ; Petržela, Jiří (advisor)
This Master`s thesis is focused on through acquaintance of principles of the function circuits with switched capaticors and posibility of their application mainly in frequency filters or signal generators. The origin of the switched capacitor circuits is mentioned at the beginning of the work. There are references to the first scientific work and scientists who have dealt with this issue. Maxwell`s idea: lossy element (resistor) replace with lossless element (switched capacitor) in electric circuit, is further described. In the next chapter of this work are listed types of switching capacitors and their use in simple RC filters and in structures of inverted or noninverted integrators and their application in more complex higher order filters. The advantages and disadvantages of SC circuits versus circuit composed of discrete components are shown. It is also listed a simple low-pass switched RC filter implemented with analogue multiplexer 4053. Using the LTC1043 integrated circuit, which structure and properties are described and analyzed in detail in the work, the 1st order aktive or pasive low and high pass filters were designed and subsequently simulated in the computer simulator OrCAD PSpice v.10. Another chapter deals with the integrated circuits higher order filters, structure and properties of the integrated filter LTC1060 are further analyzed here. Except this IC there are mentioned integrated filters commercially less available from the corporations Linear Technology and Maxim. The main objective of thesis was to propose and establish laboratory device and laboratory measurment focused on the switched capacitor circuits. The laboratory device has been designed with integrated circuits LTC1043 and LTC1060, which is demonstrated by using passive and active integrator, 2nd order band-pass and 4th order band-pass with Chebyshevovou approximation.
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Frequency Responses
Urbánek, Radim ; Kraus, Michal (referee) ; Kunovský, Jiří (advisor)
The aim of this MSc Thesis is to create a system for automatic generation of frequency characteristics of electrical circuits. These circuits are described by differential equations. A special simulator of RLC circuit has been created and frequence response, vector diagram can be generated. This system has been mainly suggested for application in education. The process of solving differential equations is based on the Taylor method. Systems in general is the theoretical part of this project. Different definitions of systems their divission ,basic phenomenons and mathematical devices are described there. Next chapter deals with the mathematical devices for solving differential equations which makes the basis for description of phenomenons in these systems. There are also systems TKSL and TKSL/C. In the next chapter I was investigaty the analyze of vector diagrams for simple and more difficult circuits. I have found a solution for actual circuit by this technique. The last chapter is devoted to the frequency characteristics and descriptions of simulation program for generation the frequency characteristics.
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Active RC filters using CMOS technology
Veverka, David ; Kledrowetz, Vilém (referee) ; Háze, Jiří (advisor)
This work deals with issues of active RC filters and their application using CMOS technology. The work focuses on basic sumarization of fundamental knowledge about function of active RC filters but it also describes basic characteristics and parameters. The defined parameters are utilized in bachelors thesis. A research has been made about the current state in discussed topic and from this research there were derived parameters for simulations that are shown in the practical part of this work.
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Loudspeaker System for Laboratory Measurements of Polar Patterns
Morkus, Filip ; Káňa, Ladislav (referee) ; Schimmel, Jiří (advisor)
In the first part the attention is aiming to the choice of suitable loudspeakers. For this choice it was necessary to set required criteria and parameters. The aim of the system was to have as wide reproducibility range of frequency as possible but on the other hand not to be too large. The other criterion was the quality of the loudspeakers and its price. In the second part there was frequency crossover suggested according to the parameters of the chosen loudspeakers. This was suggested for low frequency spectrum as well as for high frequency spectrum. When determining the dividing frequency there were thought over producer’s recommendations and frequency characteristics of the loudspeakers so that the dividing frequency was not set in the place where the loudspeaker does not have “constant” character. The third part concerns the construction of the loudspeaker case. There one can find more details about the construction of the loudspeaker system called D´Appolito and its constructional requirements. This part was kept to the previous parts because integrating “D´Appolito” needs setting the distance between the loudspeakers according to the dividing frequency. It was also necessary to count with their size. According to the loudspeakers parameters it was possible to calculate the capacity of the loudspeaker case, also its shape was said and geometric proportions were calculated. Then everything was simulated in suitable software. In the last part the complete loudspeaker system was measured in an anechoic room. There were the direction characteristics and frequency characteristics measured there. The results of the measuring were compared with the software simulations.
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Measurement of passive frequency crossovers for loudspeaker systems
Holínský, Jan ; Hanák, Pavel (referee) ; Balík, Miroslav (advisor)
The content of the master´s thesis is to approach the issue of measuring the characteristics of passive frequency crossover. The work describes individual types of measured characteristics and their possibility of measurement. Then the work describes design of modules for measurement characteristics of passive frequency crossover (shunt, resistive load and amplifier). These modules were made and tested for its functions. For the amplifier is then made a second design for fulfilment requirements. The second version isn’t made in this work. At the end of the work was prepared the theoretical part of the laboratory task: Measurement of characteristics of passive frequency crossover, including protocol.
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Frequency Responses
Urbánek, Radim ; Kraus, Michal (referee) ; Kunovský, Jiří (advisor)
The aim of this MSc Thesis is to create a system for automatic generation of frequency characteristics of electrical circuits. These circuits are described by differential equations. A special simulator of RLC circuit has been created and frequence response, vector diagram can be generated. This system has been mainly suggested for application in education. The process of solving differential equations is based on the Taylor method. Systems in general is the theoretical part of this project. Different definitions of systems their divission ,basic phenomenons and mathematical devices are described there. Next chapter deals with the mathematical devices for solving differential equations which makes the basis for description of phenomenons in these systems. There are also systems TKSL and TKSL/C. In the next chapter I was investigaty the analyze of vector diagrams for simple and more difficult circuits. I have found a solution for actual circuit by this technique. The last chapter is devoted to the frequency characteristics and descriptions of simulation program for generation the frequency characteristics.
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