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Signal Addition via Opamp

  1. Jun 3, 2011 #1
    Hey guys, first of all this is my first post in here so I hope I am doing the procedure of asking questions the right way.

    My problem is;

    I want to add two signals and generate a 1.5 period of sinusoidal wave only at the beginnig. It will be a sine wave starting at t=0 and ends at t=1.5T which looks like a "M".

    The procedure I followed (which did not work) was;

    -Apply a sine input1 with 50Hz 1V peak.
    -Apply a sine input2 with 50Hz 1V peak and 30msec delay time.
    -Sum these two by a summing amplifier.

    When I look at the voltage probes of these inputs together, when added, it seems that I will get the right kind of output but my voltage output is something completely different. It is some kind of square wave with sinusoidal peaks.

    Can anyone tell me what I'm doing wrong?

  2. jcsd
  3. Jun 4, 2011 #2
    What do you mean by 'it seems that I will get the right kind of output' ?
    (What kind of output seems to be given correctly? )

    As far I see, It depends on how the second signal applied with 30ms delay time is started. It must be started with exactly phase-out condition with the first signal. And, whether that happens depends on the signal-generator being used.

  4. Jun 4, 2011 #3
    Just figured out that there was a resistor out of value. I got it all working now.

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