Recent content by waht

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    Programs Probability from EE or Pure Math department? EE major

    The main focus of study in an EE statistics class are random variables. The book by Yates and Goodman is commonly used in many universities: https://www.amazon.com/dp/0471272140/?tag=pfamazon01-20 Also, in an introductory EE statistics class, the professor will likely assign a MATLAB...
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    Understanding AC Emitter Resistance | 25mV

    Vt = 25 mV is a thermal voltage at room temperature, about 20 degrees Celsius I believe. This value changes with temperature. It comes from semiconductor physics where you try to describe a PN junctions diode, you arrive at Shockley's equation which describes its IV characteristics. It turns...
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    Trying to understand how operational amplifiers work

    An ideal op-amp is defined to have: 1) infinite input resistance: Rin -> infinity 2) zero output resistance: Ro -> 0 3) infinite gain: G -> infinity V_{in} = V_{+} - V_{-} And V_{out} = G\cdot V_{in} This is the starting place. Every op-amp circuit can solved by applying these...
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    Current in Series: Reasons Behind Sources Not Adding Up

    KVL also breaks for current sources in series. A current source can be viewed as having infinite source resistance. That's why when you turn off a current source, you are left with an open. When two current sources are in series, one current source sees the other current source as a series...
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    Current in Series: Reasons Behind Sources Not Adding Up

    KCL at the node of two current source in series breaks down. Current into the node does not equal current out of the node. But if the current sources are in parallel, you can use KCL to add up their currents.
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    MS Electrical Engineering (Electromagnetics, RF and Microwaves)

    I didn't mention Pozar because it was already mentioned a couple of times. It's indeed, one of the best books on the subject. The non-EM approach in Ludwig and Bretcho serves as a great step up platform from upper undergrad to grad while picking up valuable theory along the way, especially in...
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    MS Electrical Engineering (Electromagnetics, RF and Microwaves)

    If you haven't taken a course in microelectronics, then study first half of Sedra/Smith. Other than that, RF Circuit Design by Ludwig and Bretchko is great resource. The difficulty level is somewhere between undergrad and graduate. It should get you up to speed. The book covers topics ranging...
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    How does Ricci curvature represent volume deficit ?

    You might be interested in this explanation (page 7) http://arxiv.org/abs/gr-qc/0401099v1.
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    Why do signals with finite energy have 0 average power?

    A periodic signal repeats itself every period: g(t+ T0) = g(t). In a sinusoid for example, g(t) = sin(t), intuitively you can say that in one period, half the time g(t) varies from 0 to 1, and half the time g(t) varies from 0 to -1. In other words, g(t) varies from 1 to -1 in one period. And...
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    Suggest Calculator For Electrical Engineering

    I've used Casio scientific calculator throughout EE, it has been extremely handy, quick and very lightweight calculator, and it can do some complex numbers as well. Many students also used this calculator. I don't think there is a need for an advanced graphing calculator. The more advanced...
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    Can Genius solve any of exercises of textbook

    A genius will ask the right questions and form new problems that no one has ever seen before, and then the genius will solve those problems, usually inventing new theory and math along the way.
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    Is this op-amp configuration the solution for measuring haze at ambient?

    You mentioned that the photodiode is a pull from a mouse. I'm not sure what kind of diode they use there. Maybe if you try a different diode you might get a different result. Forrest Mims uses a regular LED in the circuit.
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    AC Signal Amplitude Modulation in Resonant Tank Circuit

    That kind of explains it. A square wave can be Fourier decomposed into an infinite sum of sinusoids with odd order frequencies. So you could write, sqw(t) = cos(\omega t) - cos(3\omega t)/3 + cos(5\omega t)/5 ... Also, an LC parallel tank circuit acts as a bandpass filter. It's properties...
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    AC Signal Amplitude Modulation in Resonant Tank Circuit

    Does the circuit have a power source somewhere, AC or DC?
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    Reflection and transmission of signal

    What signal are you referring to, the electromagnetic waves? If so, then you need to know some properties of the wall such as permittivity, permeability, and conductivity. You can use that information to calculate the complex impedance of the wall. Then use the complex impedance to calculate the...
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