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    Pspice Buck Converter Simulation

    Greetings, Here is the list of the settings for Vpulse, V2: V1=1 V2=10 TD=0 TR=1n TF=1n PW=1m PER=2.5m Please make suggestions.
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    Pspice Buck Converter Simulation

    Good Day, I have changed the thyristor to a MOSFET and I'm trying to set-up the parameters. Please specify how I should set-up the parameters for this circuit. I believe the 10Vdc which serves as a back-emf of a motor should be changed to some other Pspice model. Also, what should we do with...
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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

    Could someone help out to understand what is going? Please provide some guidance.
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    Theory/reality mismatch in a transistor circuit

    BobK, What is then the problem with my circuit? It seems like I built the circuit correctly but due to fluctuations in component parameters I have DC supply voltage of about 14Vdc instead of 17Vdc as per the book.I will try increasing the ac supply voltage to see what happens with the collector...
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    Theory/reality mismatch in a transistor circuit

    Hello *steve*, Is it still 12V under load? or is it falling to around 10.5V? Before connecting a 4.7k resistor load, the voltage on ZD1 was 13.03Vdc. After I connected a 4.7k resistor in parallel with ZD1 the voltage on ZD1 fell to 12.97Vdc. I also monitored the voltage on source, 12Vac, and...
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    Theory/reality mismatch in a transistor circuit

    (*steve*), I measured voltages between anode of LED2 to ground and between C1 to ground. For both voltages results are 13.92 Vdc (attached). The two voltages are equal because anode of LED2 is directly tied to positive plate of C1; in reference to ground LED2 & C1 voltages are the same. Now...
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    Theory/reality mismatch in a transistor circuit

    Hi *steve*, I re-made my circuit per your suggestion (images attached). I have the following measurements: VSOURCE = 12VAC VCE = 0.069VDC VRE2 (22 OHM) = 0.91 VDC VLED2 (RED LED) = 1.58 VDC VZD1 (ZENER) = 12.93 VDC Results show that the sum of voltage equal: ZD1 + VCE + RE2 = 12.93 + 0.069 +...
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    Theory/reality mismatch in a transistor circuit

    Hello experts. (*steve*), you still haven’t provided an answer to my response about the circuit? You wrote something was incorrect; can you please point out exactly what is incorrect? My confusion is in the biasing circuit. The resistors RE2 and Rbias2 are the biasing resistors that turn the...
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    Theory/reality mismatch in a transistor circuit

    Thank you all for your responses. *steve*, the circuit you drew has the negative terminal of ‘C1’ ungrounded. However, my ‘C1’ capacitor’s negative terminal is grounded. Is that what you are referring to is wrong with the circuit? After I corrected my Rbias2 to three 10k ohms in parallel...
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    Theory/reality mismatch in a transistor circuit

    *steve* thanks for your response. Attached are also my hand calculations where I got VCE = 4.1Vdc. Also, I took photos of my connection to the source. Please let me know if it is correct. The zener is not a 12V device. I am using a 1W, 12Vdc, 1N4742A zener diode. The input voltage is not 17Vac...
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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]

    hevans1944, Thank you for your reply. My materials have finally arrived and I am connecting components together. I have also purchased a heat gun and shrink wraps to take care of my splice. As I go through my discoveries/unsats, I will write here. Thanks again for your feedback and valuable advice.
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    Building a circuit [Variac]

    Thank you all for your support and responses. What I have decided to try is to go with an AC Power Supply (link provided) which has isolation transformer built into it. The receptacle (2A max) is the isolated output. Now, just to make sure you have my blessing (as I am doing this the first...
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    Building a circuit [Variac]

    WHONOES, Kellys_eye, Now you have me interested. The safety concern with the variac is if I screw up and touch the wires coming out from the output. Please reply to my questions below: In the case I touch the wires from variac output I would be a very small LOAD and current would flow at about...
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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

    dorke, Still, not sure what to do with that third stage on pg3? The small-signal current i_b3 is zero from my calculations. Then, the only way to calculate Iout is to assume that r_e + R8 are connected to R10 and Rload via ground nodes? That's a bit confusing. Also, how would I calculate this...
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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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