Thank you for the confirmation.
There seems to be a couple of things here.
The timebase you mentioned was >20ms but the screenshot shows a 200ms timebase. Typical problems appear when using 200ms or greater AND a trigger mode. You are not using a trigger but a similar problem is occuring.
Right, so lets look at the DrDAQ. In essence it behaves like a digital storage scope but it is not a true DSO. The samples taken are digitized and sent directly to the PC. The CPU dictates the timing and the samples are stored in the driver buffer. When sampling at >=200ms/div and using a trigger, the unit will need to sample blocks for transfer to the application. Triggering is not supported outside of this block mode.
Now the problem you are seeing does not invlove the trigger. So, I think I remember from previous posts that you are using the USB adapter?? If so, then there is a solution that we are currently working on that will fix this problem. I know some changes were released in the last version of PicoScope (5.14.6), others will follow.
Michael - Tech Support
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