ok, I did now some more tests on frequencies > 5 MHz.
In general it seems that the jitter problem is not gone, but it isn't quite as substantial as what was reported earlier in this thread by other users. On my DS1054z which arrived last friday I did not notice the jitter issue when tested on frequencies up to 1MHz.
Today I hooked up my poor man's frequency generator, a AD9850 board which can generate frequencies up to (a noisy) 40MHz.
First some pictures of the rigol with/without AC trigger coupling + signal on my analog scope @10MHz and then the same with a (noisy) signal of 40MHz.
As you can see @10MHz I have jitter with both DC/AC trigger coupling. Maybe the first is just noise generated by my AD9850 board but it is not visible on my analog scope supplied with the same signal.
At 40MHz I saw almost no difference between both settings on the Rigol. On the analog scope the signal did also show up quite noisy.
@MarkL are these results consistent with your findings about the source of the jitter problem? Let me know if there are some other tests I can do to help.
The problem I was referring to is the 5us jitter. The AC coupling jitter has more consistent behavior scope to scope, and should be correctable with new firmware. Take a read through the jitter thread in blog #683, and if it's not clear what the difference might be between the two, watch Dave's blog #685 on AC trigger coupling.
What I meant by you being "lucky" is that the 5us jitter is dependent on component variations and your PLL either managed to lock, or is just not unstable enough to be visible in the time domain. If it's working well enough for you, you're in luck (although we know temperature affects it also, so hopefully it your scope will stay that way).
A more detailed sample clock test, which is the origin of the 5us jitter, can be performed:
https://www.eevblog.com/forum/blog/eevblog-683-rigol-ds1000z-ds2000-oscilloscope-jitter-problems/msg566455/#msg566455You can use Alessandro's program to do an FFT.
And also, it looks like your trigger might be set at the peak of the waveform, which is causing some of the randomness in the last couple of shots.
If you want to dig into the jitter issue, you might want to hop onto the jitter thread so we don't have another parallel thread going. (Not that THAT ever happens...)