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AC signals

  1. Oct 22, 2009 #1
    Is it possible to combine two AC signals that are slightly out of phase, but have the same frequency, voltage and current through an inductor, resistor series network.
  2. jcsd
  3. Oct 22, 2009 #2


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    You can combine them anyway, without doing anything. You just might not get a sinewave output.

    If you do a phase correction with an L-R network, you will lose some voltage so you may not have signals with the same voltage any more.

    If you are thinking about doing this with power generators in parallel, it would be better to get the generators in phase before you connect them in parallel.
  4. Oct 22, 2009 #3
    So can inductors and resistors in series align the phases of two AC signals so they add voltages.
  5. Oct 22, 2009 #4
    If you have two 10-volt, 200 MHz signals on RG-8 cables, and their phase difference is 90 degrees, put them into a power splitter/combiner like this:
    See outline at
    Put a 1.25 ns delay in one leg. The power output will be the sum power of the two inputs minus 0.35 dB.
    Here is some background theory on power combiners:
    Bob S
    Last edited: Oct 22, 2009
  6. Oct 22, 2009 #5


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    So can inductors and resistors in series align the phases of two AC signals so they add voltages.

    Within limits. The output of one such stage will be phase shifted from the input and you could bring it into phase with another signal that is not phase shifted.

    However just passing the signal through such a network reduces the voltage output.

    Do you have some application in mind? Are these signals sinewaves and at what voltage and frequency?
  7. Oct 22, 2009 #6
    The signals are sine waves at 2 volts and 60 Hz.
  8. Oct 22, 2009 #7


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    Is there a constant phase difference between them? How is it caused?
  9. Oct 23, 2009 #8
    Where do the 2 signals come from, and what do you want to do with them?
  10. Mar 10, 2011 #9
    Can i add two inverters's output. so that i could get combined value of both.

    The output AC from both is exactly at same phase difference, same voltage, same current etc.

    Please reply soon.

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