New to oscilloscopes, so I have been reading through the User Manual and testing my understanding of what I read. Came across the option to "invert" the signal. (Not sure when I would want to invert the signal, but I wanted to see it in action.)
I was curious about how well it worked so I connected 2 probes to the calibration source and inverted one, then added them together using the Math A+B function. In theory the 2 signals (CH1 & CH2) should cancel each other out with the resultant being a flat line; I wanted to see this happen.
Worked perfectly as shown in the DZ1Z_expected.jpg. But this is where things got weird...
I changed the vertical scale of CH1 from 2V to 5V. There was a noticeable relay click sound indicating a major circuit path change taking place internally in the DS1054Z. The noise level of the A+B resultant increased significantly as shown in DS1Z_5V.jpg. Not sure why this happened.
Now here is the really weird part...
Changed the vertical scale of CH1 to 200mV which caused the top of CH1 to extend beyond the display extents. CH1 obviously got clipped from the display, but the part of the signal that was clipped got removed from the Math A+B resultant and shown in DZ1_200mV.jpg.
Being a newbie, I do not think this is the correct behavior. If I had to guess, I'll bet the software is not discriminating between clipping for internal signal value limits/bounds and display bounds; there are equating the two - display clipping affects the internal value of the signal and therefore is influencing all the internal math.