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Measuring Distortions with the Scope:What you see is not what you really have..
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Performa01:

--- Quote from: Martin72 on December 26, 2022, 09:55:50 pm ---(OK, the 2nd harmonic is a little "high" (appx 0.09%))

--- End quote ---

So the third harmonic is about the same on both generators, but the 2nd is about 10 dB stronger on the SDG2000X, which is quite unexpected.

Do you happen to have some decent voltmeter that can measure down to 100 µV with sensible accuracy?

If so, please check the offset voltage on both generators and report the results here...
Martin72:

--- Quote ---So the third harmonic is about the same on both generators
--- End quote ---

It is 6dB lower on SDG1062X, the table (peaks) is a little bit irritating.
"Best" multimeter here is a calibrated brymen 869s...
Could try with it.
Martin
Martin72:
Checked DC-offset, on both generators the same (appx 400µVdc (Meter shows 0.41mVdc), output 640mVpp@50Ohm terminator).
Performa01:

--- Quote from: Martin72 on December 27, 2022, 04:35:22 pm ---
--- Quote ---So the third harmonic is about the same on both generators
--- End quote ---

It is 6dB lower on SDG1062X, the table (peaks) is a little bit irritating.

--- End quote ---

Oh yes ... maybe it would be more intuitive if you sort by frequency instead of amplitude?
Performa01:

--- Quote from: Martin72 on December 27, 2022, 04:53:46 pm ---Checked DC-offset, on both generators the same (appx 400µVdc (Meter shows 0.41mVdc), output 640mVpp@50Ohm terminator).

--- End quote ---

I'm too lazy to do a detailed calculation, but a quick estimate tells me that in this case the 2nd harmonic would be worse than -60 dBc. In other words: this DC-offset measurement is just a streetnumber (no wonder: check the specifications and calculate the error margins from that). What do you get if you measure a short? Does it show precisely 0 µV then?

Anyway, my theory was that even harmonics, especially the second, would occor especially with unsymmetric waveforms as we could get them with non-zero DC offsets. You could still try to tweak the DC-offset and see how it affects the even harmonics.
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