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1st August 2019, 08:16 #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 20,5V0,7V=19,8V. I dont know if its right.

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1st August 2019, 10:48 #2
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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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1st August 2019, 14:57 #3
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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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1st August 2019, 16:38 #4
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Re: What dc can u measure?
This same German (?) circuit is on two or more other websites today.

1st August 2019, 23:59 #5

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3rd August 2019, 03:50 #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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