Recent content by engcon

  1. E

    Can 2D FFT Convolution Be Performed Without Padding Images?

    I'm trying to do FFT convolution via the FFTW3 library for image processing purposes. Basically I have a kernel and I am convolving it with an image. A problem I encountered has to do with the dimensions of the image. When the width is not equal to the height, the pixel values I get, seem to...
  2. E

    Clock Synchronization Techniques Using 555 Timer for Accurate Results

    Hey berkeman, Thanks for your reply. I think that the method you suggested does work. I will try it for sure especially because I've never used crystal oscillators. Regarding the 555 timer, I'm synchronizing it many times per second. Since I opened the thread I came up with the idea of...
  3. E

    Clock Synchronization Techniques Using 555 Timer for Accurate Results

    Hi there, I have a clock at the receiver and I want it to be synchronized with the transmitter clock. For this reason, I send a short pulse to the receiver so that I know when a clock transition has to start. For the clocks I'm using the 555 timer. So far I tried experimenting with the...
  4. E

    Can Digital Signals Be Transmitted Over FM for FSK Modulation?

    Thanks for your reply. I must first say that I'm fairly new to this kind of stuff. If you had to decompose the digital signal into sine waves using the Fourier Series, wouldn't that require an infinite number of sine waves for perfect replication? Regarding the optimum slew rate, I have...
  5. E

    Can Digital Signals Be Transmitted Over FM for FSK Modulation?

    Hi, I'm thinking about transmitting digital signals with FM. The effect I'm trying to achieve is FSK. Can I just feed the digital signal to the input of the FM transmitter? With FSK the carrier is frequency modulated with 2 frequencies, but since the digital signal has infinite bandwidth...
  6. E

    Understanding Input and Output Resistances of an Amplifier with Feedback"

    Hi, thanks for your reply! By beta I was referring to the negative feedback, not the transistor current gain (beta or hfe). (The amplifiers in question will have to be tested with a maximum frequency of 10kHz)
  7. E

    Understanding Input and Output Resistances of an Amplifier with Feedback"

    Hi, Suppose I have an amplifier with feedback, how would I measure the input and output resistances (using instruments)? If the input of the amplifier is a voltage source, the input resistance would simply be V(signal) / I(signal). Now if the output of the amplifier is a current, would I...
  8. E

    Understanding Fourier Transforms: Solving Confusion with Even Functions

    Hi, I got a problem in which I have to find the Fourier Transform of a function f(t) defined: f(t) = { 1 - |t|, |t| < 1 0, |t| > 1 } Well , I found the Fourier transform by working out the integral f(t)e^(-iwt) with the limits being -inf to +inf (and I...
  9. E

    Load on ladder leaning against a wall

    Solved Did that, and solved it Thanks
  10. E

    Load on ladder leaning against a wall

    No mention of the ladder length is made, so I cannot use moments
  11. E

    Load on ladder leaning against a wall

    Hello, I got this problem from a book "A light ladder leans against a perfetly smooth vertical wall at an angle of 30 degrees to the horizontal. A load of 800N is placed 3-quarters of the way up the ladder. If the ladder rests on a rough horizontal surface which prevents slipping, find the...
Back
Top