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    Simple digital Bandpass Filter confusions

    Actually, my advice about using Matlab is probably the best idea for you. You can model there whatever you want and see how it interacts and it will help you understand how it all plays together.
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    Simple digital Bandpass Filter confusions

    Now you got completely lost in it :tongue2: you can not determine frequency properties (sprectrum) from a single sample. You need more than only one lonely sample filter with "unit pulses at z=4,5,6" is pretty hopeless. You need to have a deeper look at Signals and Systems As for your...
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    Telephone wiring questions

    25-pair color code 25-pair color code
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    Question about digital broadcasting

    Both standards deal with properties of communication channels for which they were designed. DVB-C (C=Cable): high SNR, no multipath, channel width 10MHz DVB-T (T=Terrestrial): low SNR, multipath, channel grid 7 or 8 MHz Both use OFDM QAM. Maybe different CRC? The latest incarnations (-C2 and...
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    Simple digital Bandpass Filter confusions

    Filters work in the frequency domain, not the time domain. If you want to just leave out some samples, design a sequential circuit (finite state machine) that copies (passing through) all samples but the ones you don't want to. Maybe if you shared more about what you want to achieve (we're...
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    Help undestanding TMDS

    The output is a digitally modulated signal, so the result is analog. That's Digital Communications 101.
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    Help undestanding TMDS

    I looked at the datasheet and it's pretty self-explanatory. :uhh: No, the inputs are parallel. You have to deliver the entire 8 bits for each colour at the same time (so for red you place a 8 bit value at DIE16-23. Check the Input Pin Description section in the datasheet PDF (p.4). No...
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    Stars vs. transistors ?

    End of the universe .. of course you can always tell him all the scientific theories about the ultimate end of the universe.
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    Stars vs. transistors ?

    I think you underestimate the number of stars in universe. Supposedly there is about 10^22 -10^24 stars (see below). I don't know how many MOSFETs have people ever produced. Say a high-end CPU has a few million gates. (10^7). People have produced ~10 billion processors (10^10) so you are...
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    Why we haven't any connection other than Delta or star in 3phase

    Is it even theoretically possible to have another connection?
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    EM Waveguide Modes: What are they and how are they used

    Imagine waveguides as oscilators, resonance circuits or antennas. You can force any frequency on them but only those with the correct wavelengths will resonate ("fit into the waveguide"). For the rest of frequencies the impedance will be high to the point of being infinite for some frequencies...
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    Square wave symmetric around zero volts

    Something like this?
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    Confusion with dB equation - 10 or 20?

    6*log I bet there are values where one must calculate 5th root of a cubic of the value but people generally don't call it "6*log" but rather "10*log of ratio of 2 values each ^(3/5)".
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    Can I define frequency for an non periodic signal?

    Analysis of aperiodic signal = analysis of series of periodic segments Sophiecentaur pretty much summed it up, I'll just say it in other words. Audio signals theoretially are not periodic. What happens in processing of such signals is that we take a section (called a frame, a window, a...
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    Why do we consider zero mean for gaussian noise in a communication channel?

    Taking it back Actually, it looks like I'll need to take this explanation back since it doesn't appear to be to right reason while the used AWGN is zero-mean. :uhh: Check also this thread: White noise in communication channel
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    Why do we consider zero mean for gaussian noise in a communication channel?

    DC component means that there is energy (power) permanently leaving the source, i.e. the source is "evaporating" so it would eventually seize to exist.
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    Please help me understand convolution

    Discrete time convolutions tutorials I meant to say "discrete time functions". I just checked Google for "discrete convolution" and "discrete time convolution" and there are some really nice tutorials and graphical explanations out there. Check out the accompanying images (discrete...
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    Electrical schematic troubleshooting program?

    I was going to say SPICE too. Wikipedia lists many other options.
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    Notifications not working

    I guess I was the unlucky one. I registered today and waited for my notification mail to activate my registration for hours. At first, I thought I mis-typed my email address. I tried to verified it only to hit the "registration exceeded for this hour from your computer" page (I haven't even...
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    Please help me understand convolution

    I believe you are wrong. Imagine each area as a series of thin vertical strips (same "time segment"). Each strip of the foreground function is weighted by the strip of the background function and these weighted results are then added (summed) by the integral. This way the integral is actually...
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    Advantage of sequential logic

    The biggest difference between combinatiorial and sequential logic is that sequential one uses memory parts (flip-flops, such as SR, JK, T, D, ...) and besides current values at its inputs can also create output(s) based partly or fully on previous values (memory parts store so-called "states"...
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    Confusion with dB equation - 10 or 20?

    I just want to clarify that when I talk about "orders" I'm talking about "orders of magnitude" (i.e. the "E" in the scientific notation of a number: M x 10^E)
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    Confusion with dB equation - 10 or 20?

    Brief answer: decibel is ALWAYS "10x". Here is why (aka very long answer): decibel is one of those unfortunate units that they tell you about at the university but spend maybe only a few minutes explaning what it really means. The unit is actually called 'Bel' (named after Alexander...
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