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  1. #1
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    What dc can u measure?

    Which DC can you measure according to picture a, b, c?

    - - - Updated - - -

    i think 19,8V because a diode needs 0,7V so 20,5V-0,7V=19,8V. I dont know if its right.

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    Re: What dc can u measure?

    No, sine peak voltage is sqrt(2)*Vrms (designated Veff in the picture).

    Without further information we should assume sinusoidal waveform.



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    Re: What dc can u measure?

    assuming sinusoidal waves, and since there is no apparent load, all three circuits act as peak detectors.

    If Veff is Vrms, then Vpeak = sqrt(2) * Veff or Vpeak = sqrt(2) * 20,5 V = 28.99 V

    remove the 0.7 V diode drop yields 28.3 V

    Since the drawing asks for Uab, point b is the reference
    the top drawing would measure +28.3 V
    the middle and bottom drawings would measure -28.3V because the diode is in the opposite direction,
    making b the more positive location



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  4. #4
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    Re: What dc can u measure?

    This same German (?) circuit is on two or more other websites today.



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    Re: What dc can u measure?

    Quote Originally Posted by Audioguru View Post
    This same German (?) circuit is on two or more other websites today.
    Obviously OP is going to take all the answers and average them.



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  6. #6
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    Re: What dc can u measure?

    Today on one of the other websites he posted a second very simple question in German.



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