Recent content by radiodude

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    Matlab syntax help using fourier series & vectors

    I'm trying to understand some MATLAB code. It's the Fourier series approximation of a signal. This is my first time using matlab, so I guess I'm really trying to comprehend the syntax. For my example, I am using some code I googled (http://www.ee.nmt.edu/~wedeward/EE341/FA97/example8.html)...
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    Signal sampled at 5000 samples/s

    If you split 10 seconds into 10 different equal time slices, what is "t" at the beginning of each time slice, if "t" is in seconds? Hint: t=0 is the start of the first time slice...what would t be for the start of the 2nd, 3rd, etc...
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    Helloi have an image and want to show its matrix represenation.

    How many pixels aka matrix entries do you have? How many bits does each take up?
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    Helloi have an image and want to show its matrix represenation.

    Yes, the above is correct, but the problem tells you something different. "The number of bits used to represent gray scale is 2, with all zeros being black, and all ones being white."
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    Directivity of array of antennas

    If my post was too long, I guess what I'm asking is this: If I know the aperture of a single antenna, how do you figure out the total aperture if you had multiple antennas? I'm tempted to just multiply the aperture of one antenna by the number of antennas but something tells me there's...
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    Helloi have an image and want to show its matrix represenation.

    The question asks you for the matrix representation. So you need to first figure out the dimensions of your matrix and based on the info given you should know how many rows / columns that matrix should have. And each pixel directly represents an entry in the matrix. You need to figure out what...
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    Electric & Magnetic Field & Polarization

    I guess what do the field lines represent? Or what does the electric field vector look like in real life if that makes sense? Thanks for the reply. I understand that type of polarization is all about the phase relationship between the x and the y component...but the x & y component of "what"...
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    Electric & Magnetic Field & Polarization

    Homework Statement I am trying to understand electromagnetic radiation...(the wave propagation of electric & magnetic fields) and resulting polarization. I just cannot visualize it, and once I think I understand, I see some diagram which challenges my thinking. What is the relationship...
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    Directivity of array of antennas

    Homework Statement I am trying to understand how the total directivity of an array of antennas is calculated. Homework Equations 1. A_e = (D * lambda^2)/(4 * pi) where: A_e = effective aperature (or area of antenna) D = Directivity of one antenna lambda = wavelength 2. D_t =...
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    LM3940 regulator not putting out 3.3V

    Thank you guys for all the responses. I guess I need those caps there. I designed the board with the caps in mind but I guess my preliminary testing before I soldered them in made me feel something was wrong altogether. I'll just wait & see what happens after the caps are in. I'll be honest I'm...
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    LM3940 regulator not putting out 3.3V

    That's the last thing I haven't tried yet (ordered some, waiting for them to arrive). But I didn't think the caps not being there would make a difference if I threw it a steady voltage. Could they really be the culprit? If so, why?
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    LM3940 regulator not putting out 3.3V

    I'm giving it exactly 5 volts directly from a DC Power Supply and the output voltage should be 3.3V but it's not. I don't even have anything connected to the output pin of the regulator (holding it in my hand). It seems if V_in < 1.5V, V_out = about 0 plus a couple millivolts V_in >= 1.5V...
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    Diode Logic Gates circuit analysis?

    I need to understand how diode-resistor gates work. I've read a lot about what's supposed to happen based on inputs, but I need to see some numbers & analysis to understand what's going on. Where do you start in terms of trying to analyze the following AND gate...
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