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    Pspice Buck Converter Simulation

    Greetings Experts! I am trying to solve a homework problem on the subject of Power Electronics (DC-DC Converters--Buck Converter). The following problem statement has been provided: 1. Ideal source battery = 100Vdc 2. Load = Series combination of resistor (0.25 ohm), inductor (1mH), battery...
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    Full-Wave Single-phase Controlled Rectifer

    I need help calculating the RMS value of the fundamental component of source current. The electrical circuit is a fully controlled single phase rectifier bridge. In the lecture the value is:
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    Theory/reality mismatch in a transistor circuit

    Good Day, I am having difficulties getting the results as described in the book (attached). My base current is only 2.67mA and collector current is around 30mA. The transistor I am using is MJE2955T, as recommended by the author. Below is a list of measurements I performed with a multimeter...
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    Building a circuit [Variac]

    Hello friends! I am trying to build the circuit attached below and need your advise on picking the right transformer. I am currently thinking of buying a variac so that I am able to not only use it for 12VAC but for any voltage I would like. However, looking at this particular variac on Amazon...
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    Principles of relays [Understanding Textbook]

    Greetings experts in electrical engineering. I need your help in visualizing how a circuit would look like after a 'short circuit' event. Reading Electric Relays - Principles and Applications, I got confused about the statement highlighted in the attachment below. Modern electromagnetic current...
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    BJT current gain

    Hello guys, I need help with the problem below: I'm having difficulty finding Iout in terms of small-signal ib_3 of Q3. My work is attached below under spoiler. It seems that the dependent current source for Q3 is open (Off), so then looking at my pg 3 I'm ambiguous about finding Iout in terms...
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    Impedance of two stage amplifier

    Hello, I need a clarification regarding the overall gain of multi-stage amplifier and finding equivalent resistances seen by capacitors. Let's consider the ckt below: When I tried to figure out the overall gain, Av as: I considered RL1 as R11 + R10; however, from the solutions my answer is...
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    Cup with heat awareness

    Hello guys we need help building a cup that would notify drinkers of hot beverages of the temperature via LEDs. Namely, if the liquid is hot - red light, warm - yellow light, cold - green. The trouble is how to power the circuit. We are not allowed to use lithium-ion batteries, only Ni-Mh...
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    Simulating in Pspice

    Hello, I'm trying to simulate a common source with and without a capacitor and for some reason get awkward results. The current shown leaving the source is 0, how can that be? Also, the current and voltage on the load are zero. I need to find out the overall gain of the ckt, Av, the input...
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    Zener diode

    I'm having trouble understanding how to find the slopes in this circuit: Problem statement: The PWL model for the Zener diode in the circuit above is shown below. The source is a triangle wave, as shown below. Sketch the voltage across the Zener diode. Indicate voltage levels of both the...
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    Thevenin voltage

    Hello, I need help with figuring out the open circuit voltage in the circuit below. Namely, the question is asking to plot Vz(Vs) and in order to do that we need a series circuit where the Zener diode is our load. However, when I go to verify my answer with the solutions, the Vth value is wrong...
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