- Rigol should google faster implementation of embedded FFT, their slow processing is not sooo Cooley-Tukey.
I do care a lot more to resolution and dynamic range, of course any improvement for update speed will be appreciated.
i thought they fixed the sample clock jitter long time ago...
i thought they fixed the sample clock jitter long time ago...
Hi
Yes indeed they took care of an absolutely rotten jitter / phase noise / spur problem and turned the clock into something that is not quite as bad. The gotcha is that they still have "stuff" quite high up on the clock noise / spur wise. Dave has a spectrum plot in his video on the fix. That noise is going to be a big limiter on FFT.
Bob
Sorry I might have been living under a rock, but which version of firmware has the improved FFT?
i thought they fixed the sample clock jitter long time ago...Hi
Yes indeed they took care of an absolutely rotten jitter / phase noise / spur problem and turned the clock into something that is not quite as bad. The gotcha is that they still have "stuff" quite high up on the clock noise / spur wise. Dave has a spectrum plot in his video on the fix. That noise is going to be a big limiter on FFT.
BobIt remains to see what other scopes (of the same market segment, please ) have inside under this aspect, anyway i guess not on top of limiting factor list.
I do care a lot more to resolution and dynamic range, of course any improvement for update speed will be appreciated.i have a suspicion that due to their slow algorithm, they have to limit their sample count to some abysimal value like 16Kpts. if this is the case, increasing sample count will result in crawling turtle fft screen update. i cant think of any other reason with this 24Mpts machine...
i thought they fixed the sample clock jitter long time ago...Hi
Yes indeed they took care of an absolutely rotten jitter / phase noise / spur problem and turned the clock into something that is not quite as bad. The gotcha is that they still have "stuff" quite high up on the clock noise / spur wise. Dave has a spectrum plot in his video on the fix. That noise is going to be a big limiter on FFT.
BobIt remains to see what other scopes (of the same market segment, please ) have inside under this aspect, anyway i guess not on top of limiting factor list.the problem with rigol is too many people dicking around with it. people ask too much to their desire thinking rigol can satisfy everybody. now we are going to the nitty gritty detail of how a sampling is performed in a dso. i read a pdf in the net, agilent iirc about how we live in imperfect world that no sampling module can perfectly sample at absolute perfect dT everytime, this will affect anything on the output you name it, FFT, interpolation, jitter, noise thd analysis etc.. you want perfect, pay premium... yes i will look forward Dave to measure spectrum of other DSO's clock, then we can judge which one is the most perfect clock apple to apple...
They might be doing it on the main CPU where other scopes are doing it in an ASIC/FPGA.
I do care a lot more to resolution and dynamic range, of course any improvement for update speed will be appreciated.i have a suspicion that due to their slow algorithm, they have to limit their sample count to some abysimal value like 16Kpts. if this is the case, increasing sample count will result in crawling turtle fft screen update. i cant think of any other reason with this 24Mpts machine...
They might be doing it on the main CPU where other scopes are doing it in an ASIC/FPGA.
If only the source code was loaded on GitHub ... LOL !
If only the source code was loaded on GitHub ... LOL !
If Rigol really wanted to kill the opposition forever, that would be the way to go. I'm sure there's plenty of people out there who could optimize the code and extract a lot more from the hardware.
And I could fix some of the UI nasties.
If Rigol really wanted to kill the opposition forever, that would be the way to go.
As far as you know, there are precedents for DSO's public source code ?