2,Square Wave and Rise Time
In the SDG1000X PLUS datasheet, the rise time is 10-11nS.
1Mhz and 20Mhz Square Wave, 10.3nS rise time


When I set a fast rising edge triangle wave, see what happens

Rise time is 5.38nS!
3, Higher frequency output
As the top model is 60Mhz, I want try some tricks on my 25Mz model see if it can do higher waves, it actually puts 5.38nS rising time right?
I've tried to create a file containing multiple repeated waveforms and output it in True Arb mode. As the True Arb mode is point-to-point output and the maximum sample rate is 250M, there will only have 4.16 points at each wave if I need to output 60Mhz.
It works. But the wave frequency is coupled with sampling rate, NO stable output at most time. It dose stable just on certain specific frequencies.
Next I tried to use DDS mode, the output was still unstable. Given the way DDS works, the waveforms I created before may have too few points. So I created a 256k waveform consisting of 5 repeated sine waves, and then, the magic happened

20Mhz Arb in DDS mode, outputs 100Mhz sine wave! the rise time is just under 3nS!!

You can see that the 100Mhz sine wave is very clean, even cleaner than the old Rigol DG1022U at 20Mhz I used before.
I also created a 10 repeated sine waves Arb to test higher frequencies, the output rapidly decays right after 105Mhz, which shows the limit of the output stage bandwidth also the 250M DDS generator.