Hi
Can see that KedasProbe is having fun with his new scope...
Having seen HMO FFT's screens I have to say it looks very nice...
..
As per KedasProbe request for Rigol screens and to check about nctncio triangle shots,
I have spend some time with my old Rigol DS1052E and run some tests,
so KedasProbe and other HMO owners can see how nice FFT they have...
I hope it will add some practical, real life info to this discussion.
Would be perfect seeing something similar run on HMO scopes.
So There are some Triangles...
My Tek TDS744A also has a so called hi-res mode (10 bit). I set my signal generator to generate a triangle wave and made it fill the screen of the scope (first picture). Then I fed the same signal through a 40dB (100*) attenuator and set the scope to 100* magnification (second picture). Now check the differences. When the signal is magnified 100* you are looking at about 1.33 bits of the ADC. Now try to FFT that. A sine wave won't be so bad but a more complex waveform like a triangle is perfectly suitable to make imperfections visible.
Note that I used the trigger output of the generator to trigger the scope on the 2nd channel so the trigger is the same for both situations.
So there are Triangles @10kHz run from Siglent SDG1025..
Screens are with Rigol FFT option set for full screen and markers @dBVrms .
First "full screen" Triangle @ 200mV/div that goes about 1,5V p-p.
then just FFT screen at 10kHz/div , so You can see just FFT more clearly.
Then 100 times attenuation that is 15mV @ 2mV/div
And again just FFT screen @ 10kHz/div and second FFT @ 25kHz/div so You can see that there is no distortion or any problems till about 300kHz. Everything looks nice and smooth as expected.
Wonder what is at nctnico screens.?
I went even bit further..
to.. 5mV p-p triangle..and even to..1mV p-p.
That are special shots for guys that are complaining at DS1052E scope noise...
Still all looks nice and smooth ...
So hope it is pretty safe to say that SFDR or dynamic range at THE CHIPEST RIGOL scope seems to be at list about 60dB.
And second is that FFT noise floor at THE CHIPEST RIGOL scope is about 108-110dBVrms.
And even with THE CHIPEST RIGOL scope some measurment can be done..
Hope that it will help a bit.
And again and again and again .... would be perfect seeing something similar run on HMO scopes.
Or actually any other scope.
Rosendorfer
Bit more in second post.