Hi @ps_Water
Great to hear things are working! I will mark my previous reply as the solution, but please post below with more questions or issues.
Downsampling
Your Joulescope JS110 always samples at 2,000,000 times per second (2 Msps). The JS110 forwards the raw sample data to the host computer. The host computer then applies the calibration and performs some processing to produce the real data in SI units. When you change the sampling_frequency you are actually inserting an additional processing step on the host computer that performs downsampling. The software applies a digital filter to prevent aliasing, then discards samples to reduce the frequency.
An interesting side-effect is the JLS file. In full 2 Msps mode, the JLS file stores the raw samples. When you load the file, the software converts these raw samples into SI units, just like when they come from the physical instrument.
We can no longer do this in the downsampled mode as things like the current range have already been applied. Instead, they are stored as float32 values. So, the data format stored in the JLS file changes when you select downsampling.
You can see this effect in the data bandwidth required for each downsampling ratio.