Products > Test Equipment
How much noise floor and other things matter in oscilloscope usability
<< < (11/63) > >>
Fungus:

--- Quote from: Fiorenzo on December 24, 2021, 08:07:55 pm ---
--- Quote from: Fungus on December 24, 2021, 07:41:06 pm ---OTOH you could even go down to a 500 Euro oscilloscope like the Siglent SDS1204X-E. It's probably all you need and you'd have enough money left over to create an awesome lab.

--- End quote ---

Yes I know, this is one of my doubts. I will check some review of that scope but in the mean time what do you think about its bigger brother sds2000x-plus?

--- End quote ---

Me? For that money I'd start with the little brother plus 1000 Euros of other toys(!). When you know more about oscilloscopes and their limitations you can decide if you want to sell it and buy the bigger one.
Fungus:

--- Quote from: Fiorenzo on December 24, 2021, 08:20:51 pm ---4) 100mv/div, probe, all the same


--- End quote ---

Looks flat enough to me.  Nothing to be unhappy about.

What about 1v/div with 10x probe?
Fungus:
Also try averaging mode:



(image from section 4-5 of the manual)

Averaging can be used with any periodic waveform, ie. almost all waveforms where noise might be an issue, eg. measuring ripple.
Fiorenzo:
With 1mv/div It gives about 160mV RMS and 1,2mV peak to peak. Whatching other scopes they seem to have about 4 time less noise.
Am I wrong?

About me I am not rich, but I would like to buy a quite good oscilloscope.

I dislike to spend a lot of money ofcourse, but in my experience with quality instruments you get the best results from what you are doing so maybe a big effort now could be a big help tomorrow, or maybe It Is better that now I spend a little amount of money and wait for more evolute oscilloscopes in the future....

If the 1000 series is good for me I take It, if It Is better the Rigol or the 2000 series i will go for It but at the moment I am unsure on which way to take.

You speack about other usefull instruments, what could I buy?
I have the solder station and some fixed voltage psu and one psu I have made by my self with 4 indipendent regulable output but not very precise....
bdunham7:

--- Quote from: Fiorenzo on December 24, 2021, 08:20:51 pm ---Here I am, I did the test you asked for, please let me know whath do you think about It.
Thank you very kind!

--- End quote ---

So just as a quick apples-to-apples comparison with your first example, I set up an SDS1104X-E with the same no-probe, 20MHz BW, 5us/div and 1mv/div.  Then I connected a 1mVrms 100kHz signal so you can see the suitability of the scope for viewing such a signal.  The noise makes it a bit jumpy and jittery because it affects the trigger point.  I have some low-frequency noise that isn't from the scope but is from other stuff that I have around that I can't turn off right now, so I did both a live snapshot and a stopped picture, which is effectively a single-shot.  As you can see, the scope is perfectly usable on 1mV signals and your Rigol, which is over 3X as noisy, might have a tough time with the same signal.

I also took a snapshot with the input set to GND, which shows you the ADC noise, or so I think.  The LSB at this setting is 40uV, so the peak-to-peak noise is 1 bit. 

I can't tell you what scope works best for you, but if you work at all with small signals, the front-ends of the entry level Siglents is definitely the best for the buck.  Features like the ERES acquisition mode and the 10-bit mode of the SDS2000X+ series do make them better, but you shouldn't generally count on multi-capture averaging even though it can look very good, as this can lead to errors.

Navigation
Message Index
Next page
Previous page
There was an error while thanking
Thanking...

Go to full version
Powered by SMFPacks Advanced Attachments Uploader Mod