Recent content by go2255

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    Designing DC motor with 8051 and transisors

    I want to design a bidirectional DC motor , so I use four transistors in the H bridge circuit. Is there any problems if there is no resistors in the base of transistors? How can I use 3 buttons for stop,forward and backward control of the motor? Where should I put them? Which pins of...
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    Designing DC motor with 8051 and transisors

    I want to design a bidirectional DC motor , so use four transistors in the H bridge circuit. I can understand the first circuit, but for the second, I can't understand why input signal , eg: A, is connected to the same side of transistors? What is the differences, which one I should...
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    Lab-3 phase star connected system

    Homework Statement Is common point(O) equal to netural terminal? eg: Vo=Vn?? V(L1-o)=V(L1-n)?? The Attempt at a Solution The first one is what I measured in a lab. The second one my prediction if the phase reversed,base on the first one is it reasonable?
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    Is a Binary-to-Gray Code Converter Considered a Decoder?

    Homework Statement Binary-to-Gray code converter,isn't it a decoder? The Attempt at a Solution
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    K-Map & Logic Gate Help: 4 Variables x3, x2, x1, x0

    Homework Statement There are four variable(x3,x2.x1,x0),how should I put them on a K-map? Is it like that? The Attempt at a Solution
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    Norton theorem,max. power transfer

    Homework Statement How should I calculate the max. power transfer to Xload? The (20+30j) of Xload,it is not necessary. Homework Equations I try to find the answer,but I got two answers by different method. The Attempt at a Solution
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    What is the Correct Calculation for Transistor Configurations?

    This is the result from a lab,but I am not sure the results are correct. I guess the combination of R1=10k and R2=10k is under linear region,but how come the calculated Ib is zero. For combination of R1=10k and R2=1k,Idon't know why the Ie is negative.Negative value means error?Is it the...
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    BJT Homework Help: Troubleshooting Results

    This is the result from a lab,but I am not sure the results are correct. Also,when I try to find I(c) , I(b) and I(e),by measured V(RC) and V(RE),I find the results strange. I guess the combination of R1=10k and R2=10k is under linear region,but the dc gain is so small. For combination of...
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    Solving Capacitor Circuit: 3nF, 4nF & 5nF w/ 20V Supply

    Homework Statement A 3nF Capacitor is parallel with a 4nF Capacitor. And they are connected with a 5nF Capacitor in series. IF the external voltage supply is 20V. FIND (a)the p.d across each capacitor, and (b)the total charge in the three Capacitor. The Attempt at a Solution (a)...
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    Finding Iz and Is for VZ = 7.2V with RL = 10Ω

    I don't know how can i find the Iz and Is. The zener voltage VZ = 7.2V, with the condition that the zener current 77mA ≤ iZ ≤ 1A load resistance RL = 10Ω. What is resistance RS when load voltage VL is regulated to 7.2V while the input voltage Vin varies by ±10% from its nominal...
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    How Do You Calculate the Total Moment of Forces on a Plane?

    I heard that the moment of F about point a is (r-r(a))xF but i can't understand what r and r(a) are.And when there are 2 forces act though different point,how can I find the total moment. e.g: Four points:O(0,0,0) P(9,-3,5) Q(6,4,7) R(3,2,3.5). OPQ is a triangular plane and R is a point on...