When I set an external Agilent source to 25MHz and 1Hz increment, I can adjust the frequency modulation of the jitter band to nothing. At a 1Hz step away from "no band", I can watch the wave move left to right with a 1Hz period.
All the while, the right most wave remains stable and unaffected.
This is an MSO1104Z received in the past week, latest firmware. Trigger is AC coupled.
Likely because of the update rate.
At 1s trigger holdoff the scope only triggers once per second, but it replays the artifact at a very slow rate.
At full speed the scope does several thousand of updates per second (50ns seems to be the sweet spot in the v2 firmware - 30k wfms+), so you don't see how it dances around so well.
Can't confirm neither of these issues on my DS1104Z purchased this spring. Software version 00.02.03.SP5. Hardware version unknown, it is just not displayed on the sysinfo screen.
No jitter at AC coupling at any offset, and no jitter at DC coupling - tried multiple offsets, 0, 0us, 10us, 15us, fractionals of those.
Attached is a screenshot of 15MHz being fed directly from HP 33120A signal gen, shifted 5us from trigger point. The voltage shown is wrong of course because it is expecting the 10x probe divider instead of direct BNC-BNC cable.
There is other issue with this scope that drives me mad: a very slow response from the vertical offset knob. Does anyone know if there is any software update that would fix this problem?
The trigger needs AC coupling for it go berserk.
Also the artifact I have shown only settles in at >22.5MHz. Lower than that and it looks identical to the AC triggering issue Dave showed, the triggering is jittering. A coincidence: it also happens at half 22.5MHz -> ~11MHz. There is a band where the artifact is present. Around 15MHz it's already gone.
It also seems to do that when there is no DC offset. When there is a DC offset, it looks like "normal jitter".
I also noticed that if I do set the trigger level higher, I can put it near the peak of the sine wave and the jittering stops. Actually it's around the point the built-in hardware frequency counter has no trigger to count the frequency anymore. Coincidence?
See here; AC trigger, point @ 400mV (top right corner):
https://dl.dropboxusercontent.com/u/207647/Amplitude%20800mV.pngAutomatic measurements measure 800mVpp for a 900mVpp generated signal. It's probably a combination of both the scope and function generator that's slightly attenuated. Unfortunately the effect is not that strongly present at 12.5MHz. Notice there is no hardware frequency.
https://dl.dropboxusercontent.com/u/207647/Amplitude%20900mV.pngAnd the artifact is back, plus the frequency counter.. well sort of. If I were to increase the amplitude even more, it would come back.
I also notice that if the V/div setting I need to move the trigger level otherwise the waveform updating stays frozen. Wonderful.
It happens on any channel. Enabling 2 channels doesn't seem to make it worse or better - it's as bad.
The trigger OUT seems to jitter even with DC coupling; although thanks to the intensity grading it seems like the jitter band is smaller (about half) and more concentrated at 1 point. It also delayed by about 350ns.
AC trig out:
https://dl.dropboxusercontent.com/u/207647/TRIGOUT%20AC.pngDC trig out:
https://dl.dropboxusercontent.com/u/207647/TRIGOUT%20DC.png