الفهرس 
AcknowledgementOnly 14 pages are availabe for public view
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Abstract
A digital Impedance Bridge that utilizes the principle of three voltmeter method is designed . The three-voltmeter method has the advantages of simple setup circuit design and do not need complicated balancing techniques which make it suitable for automation . The main error in this method arises from the error in measuring the voltage values . Since the resolution of the DAQ board we used is 16 bits we expect that errors due to A/D conversion will be in the range of 0.305 my for +_ 10v range . the bridge is constructed with commercially available data acquisition board which exists in the form of peripheral control interconnect (PCI)cards which incorporated in personal computers . As the DAQ board we used has analog output we used it not only to record the voltages but also to synthesis the excitation signal to produce a fully automated system . The data acquisition program is written in lab VIEW programming language , this generates the excitation signal at the desired frequency , measure the voltage values , compute the impedance and write the results to spreadsheet file.