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    Increasing Frequency With Time

    Have you considered a design with two down counters? Use a pre-settable down counter to divide a clock that flashes the light. Load the MSB bits from the main countdown timer into the down counter which then should flash the light faster as the MSB bits fall to a lower binary value.
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    help me about slew rate

    When I had the idea that the slew rate might correlate with the unity gain frequency, I checked it against the datasheet for the NE5534. It seemed to correlate rather well. However, I just realized that the scale for Fig 3 is not V/mV as shown in the graph (in error) but V/V. So any empirical...
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    help me about slew rate

    One way to make an 'estimate' from the available data could be at the unity gain frequency. Just assume a sine wave at this frequency has maximum amplitude (rail-to-rail?) then find dV/dt at the zero crossing. That will be the slew rate (at least as derived from the available data).
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    FFTW???

    Nin=Nout -- This is true; however, the output is folded on the frequency axis so that there are only N/2 meaningful frequency bins. Note: Image extracted from document available online at university in Argentina. http://www.ingelec.uns.edu.ar/pds2803/Materiales/LibrosPDF/Brigham/TOC.htm
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    FFTW???

    The answer could depend on whatever scaling factor your FFT code may have built in. I would suggest constructing a sample set as you have described, and then run it through your FFT to see what it gives. All we can say for sure is that the 0 bin should reflect the DC value of the input sample...
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    Total Resistance of circuit, when there is current source

    But to answer the OP's question, the internal resistance of a current source is infinite so for the purpose of calculating circuit resistance (whatever that may mean) the current source is replaced by ∞Ω.
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    Total Resistance of circuit, when there is current source

    The question of the reference was answered when the problem provided the open terminals. There is no logical reason to assume the problem means anything else than the equivalent resistance at the open terminals. Of course, if the problem actually stated something else then I would go with that.
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    Total Resistance of circuit, when there is current source

    Is there any possible logical reason why the problem would be asking for something other than the Norton or Thevenin equivalent resistance? Maybe just to confuse the student?
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    Binary Counter

    I tried doing that on my Windows 7 but it did not work:
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    Shadow signal

    This is an ideal function for a micro-controller; however, the learning curve for using a micro-controller is quite steep. But if one is over that hump then the whole thing, including generation of the original pulse train and the delayed shadow pulse, could be simply implemented with a...
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    FFTW???

    While I'm not familiar with FFTW it is based on using the discrete Fourier transform. If you need the first harmonic at 20 Hz, then the sample period must be 1/20 = 0.05 sec. To get results to 20 KHz the sampling frequency must be at least 40 KHz. So the number of samples is N=0.05*40000=2000...
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    TDS460 oscilloscope

    Have you performed the primary troubleshooting procedure from the service manual? The service manual also makes it clear why no schematics are provided. Is it normal procedure to ignore the service manual?
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    Help with RS485

    Recommend the following source to aid decision whether 1-wire is suitable for your application: Guidelines for Reliable Long Line 1-Wire Networks
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    Help with RS485

    It's not clear how you intend to incorporate a bus master for the master/slave bus protocol. Right now I have to assume that the PC connected through the RS232 interface is the bus master running the control software that insures only one slave node transmits on the wire at any one time...
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    Kirchof's law with Current?

    First off, this is KCL so starting with loop currents is a mistake. Kirchoffs Current Law or KCL, states that the “total current or charge entering a junction or node is exactly equal to the charge leaving the node as it has no other place to go except to leave, as no charge is lost within the...
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    Boolean Algebra Simplification

    In that case, I would suggest simplifying the algebra in the same way that the K-map is simplified. In the initial sum of minterms, certain ones will be repeated in duplicate or in triplicate. Those that are within two circles in the map will appear twice; those within three circles appear...
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    Boolean Algebra Simplification

    All you need to do is draw three circles on the K-map and you get the answer.
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    LC circuit in the time domain

    One should first clarify whether the interest here is in the complex frequency domain, where the complex frequency variable s=σ+jω, or in the steady-state frequency domain where σ=0 and s=jω. In the complex frequency domain it is possible to analyze how a circuit reacts to transient events...
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    LC circuit in the time domain

    The simple answer is that capacitors and inductors are treated as linear devices so that an LC combination is a linear circuit that can only produce a linear output. A circuit with an input of sin(ωt) and an output in the form of sin²(ωt) would be a non-linear circuit; therefore, your...
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    pullup and pull down resistors

    Absolutely not! The transistor datasheet will give maximum/minimum/typical values for its performance parameters. To choose pull-up/down resistor values one needs to look at the driven load for its device requirements. The transistor datasheet will only help you decide whether it can be used...
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