Yes, this is a memory thing. Any scope will do this if you zoom out far enough, but the point at which it happens is a function of sample rate and memory depth.
Thanks !
I was not sure , because on Siglent I reduced the memory to 14K (7 times smaller than 100k on EDUX) and waveforms seems still recognizable . But maybe at deeper zoom levels it doesn't take account about my settings , something like Keysight do with automatic memory allocation .
About 1Mpts. of memory ? Not even as paid option ?
A key difference between Keysight and Siglent scopes is that Keysight always uses the maximum amount of memory available and Siglent (by default) only uses enough memory to fill the screen. On the Keysight you can zoom out and see more of the signal when using short time/div settings. On the Siglent OTOH you'd need to recapture the signal and then zoom in which is kinda clunky.
Tis is true about Siglent but bit loosy to say that it uses just enough memory to fill the screen.
With example 1ms/div it use default 14M memory. Is it just enough for fill the screen? Or is it bit more... This all is mapped to display width. This all memory lenght is also with full data used for measurements. Screen show always full captured length. No visual blind time. With Siglent hardware based zoom you can zoom from 1ms/div down to 1ns/div without loosing trigger stability. Still less than 100ps trigger jitter. If no need fast update rate, just keep scope 1ms/s and use zoomed window with timebase needed. All can do in zoomed window or upper window. Even measurements used data resolution is same. Even when 14M is mapped to 700 pixel wide display.
But if display vertical dimension is more then I like it more.
Siglent is bit different compared to many other scopes what use long memory and time base is just nearly as full window zoom.
handling Siglent need bit different adjustment/handling practice than this other style. It takes quite short time to adapt this method. If can not adapt and learn other handling-adjustment practice - then it may feel difficult.
I remember old golden times when I have adaped to use Tektronix scopes. Oh well...one day I need use HP scope. First feel was that with this can not do anything...total crap...let me throw this out from window.. Until I have experience with it and adapted to use just bit different, perhaps some things (UI) was even better than in Tek. After then later when I use again Tek. It did not anymore feel so good - not anymore like "leader". (but this time was analog scopes time)
I do not say that other method is universally better than other (Sig vs many others). But they are different and need different handling practice in muscle memory.
Why Siglent need copycat others? If one duck turn his head is it so that all other ducks need also turn heads. Markets are free and open. Everyone can buy what he like or need or want with his budget.