UPDATE FROM RIGOL
Short and not explanatory, but:Quote1: We have reproduced the two issues in R&D side;
2: All issues can be fixed by firmware updating without deleting any feature;
3: The trail firmware form R&D will be released in early next week, that can be used for Dave or some urgent cases.
UPDATE FROM RIGOL
Short and not explanatory, but:Quote1: We have reproduced the two issues in R&D side;
2: All issues can be fixed by firmware updating without deleting any feature;
3: The trail firmware form R&D will be released in early next week, that can be used for Dave or some urgent cases.
This update must be false as I received an email from them this AM stating:
"Ok. Excellent. Thank you very much for the video.
We haven't been able to reproduce the issue on units that we have here.
Would you be willing to be without the scope for a week or so?
We would like to ask if you could ship the scope to us (we will send you a FedEx label.. just need you to box it up and ship it) for further testing?
We will test it with beta firmware revisions and then ship it back once we have a solid fix in place.
WRT the 30 day return.. we are extending it until we get the fix from Engineering.. so, no risk from that standpoint."
You can only achieve increased resolution if there exists 1LSB (or more) of Gaussian noise on the signal. If the signal is not sufficiently 'noisy' within the window of the averaging filter, it won't work properly.
According to who? I posted a paper that clearly documents both the mathematical method and effect of successive sample averaging - which, BTW, doesn't mention anywhere "adding 1LSB of noise" - but you've not posted any substantiating material.
Resolution will
always be improved on those portions of a signal that slew
through multiple code counts between samples, but steady-state
signals will see improvement only if there is noise present with
amplitude greater than 1 or 2 ADC LSBs.
QuoteTektronix scopes implement high-res correctly and consistently achieve increased resolution, even for noiseless DC.
Again, I'm afraid you would need to post actual documentation proving your assertions.
The DS1000Z is definitely increasing the effective resolution - but by only 2 or 3 bits - I can see this clearly on the DS1000Z I have.
The scale of the display does not change but the waveform record is not 8 bits in the case of the TDS series and similar old Tektronix DSOs and does not even match their digitizer resolution.
From the paper that you posted:Quote from: 'the paper'Resolution will always be improved on those portions of a signal that slew through multiple code counts between samples, but steady-state signals will see improvement only if there is noise present with amplitude greater than 1 or 2 ADC LSBs.
Adding 1LSB of noise solves that problem entirely.
Observe the youtube video i linked in Reply #390. It is obvious that there is FAR more than 8 bits of resolution on the display as there is no significant pixelation visible even though the signals are scaled to only a small fraction of the vertical span on the display.
I observed the video - it proves nothing about Tektronix adding 1LSB of noise. Whatever averaging it's doing has to be eventually downsampled for the 400 pixels of vertical resolution. Could you please post some documentation from Tektronix that describes them introducing 1LSB of noise before successive sample averaging? That alone would convince me that they're doing it.
Dither is a random signal that is added to the input signal to smear its energy across multiple A/D codes, effectively averaging the individual DNL errors across all the codes.
Guys sorry for jumping in. This thread is for the Jitter problem . Unless i misunderstood , may i suggest the Hi-Res discussion to be moved to a separate topic.
Guys sorry for jumping in. This thread is for the Jitter problem . Unless i misunderstood , may i suggest the Hi-Res discussion to be moved to a separate topic.
The scale of the display does not change but the waveform record is not 8 bits in the case of the TDS series and similar old Tektronix DSOs and does not even match their digitizer resolution.
Yes - the waveform record (or sample memory) - but this is irrelevant to the real-time display of the waveform, only to external post processing.
With that resolution, how hard would displaying anti-aliased graphics be? I would sacrifice waveform update rate with accuracy.
Guys sorry for jumping in. This thread is for the Jitter problem . Unless i misunderstood , may i suggest the Hi-Res discussion to be moved to a separate topic.
I do not think it is to far off topic to mention other bugs to the same instrument,
UPDATE FROM RIGOL
Short and not explanatory, but:Quote1: We have reproduced the two issues in R&D side;
2: All issues can be fixed by firmware updating without deleting any feature;
3: The trail firmware form R&D will be released in early next week, that can be used for Dave or some urgent cases.
This update must be false as I received an email from them this AM stating:
"Ok. Excellent. Thank you very much for the video.
We haven't been able to reproduce the issue on units that we have here.
Would you be willing to be without the scope for a week or so?
We would like to ask if you could ship the scope to us (we will send you a FedEx label.. just need you to box it up and ship it) for further testing?
We will test it with beta firmware revisions and then ship it back once we have a solid fix in place.
WRT the 30 day return.. we are extending it until we get the fix from Engineering.. so, no risk from that standpoint."
Alternatively, the person who emailed you was not informed..
Are you kidding me! I have a hard time believing they have no scope to test with. They want to use my personal scope for testing??? Seems like a mickey mouse operation. Lets see... I purchase a new scope so they can do R&D.
I am very disappointed in the way this whole thing has been handled. This is the last Rigol product I will purchase.
Rigol, Send me one of the working scopes you have. and I will gladly send you this broken one for R&D.
From what I remember of the TDS series, high resolution mode may be used in place of averaging for this so an acquisition record of greater than 8 bits is created and transferred to the waveform memory.
To sum up the above, the waveform record on these oscilloscopes is greater than 8 bits and may be displayed in real time showing resolutions greater than 8 bits when averaging or high resolution mode is used during acquisition.
Some of their known quirks like making automatic measurements on the display record imply problems.
H.O. can you post that same image at T=0? Does it look better at T=0?
Well, luckily there's this newfangled contraption called The Internet that can supplement memoryUnfortunately, after much digging, I can find no documentation that any Tektronix DSO/MSO specifically creates waveform records of greater than 8 bits when using Hi-Res
Take example TDS series programmers manual (TDS410 up to TDS784).
2nd email from them this AM in response to the questions document.
"Ok. Excellent. Thank you very much for the video.
We haven't been able to reproduce the issue on units that we have here.
Would you be willing to be without the scope for a week or so?
We would like to ask if you could ship the scope to us (we will send you a FedEx label.. just need you to box it up and ship it) for further testing?
We will test it with beta firmware revisions and then ship it back once we have a solid fix in place.
WRT the 30 day return.. we are extending it until we get the fix from Engineering.. so, no risk from that standpoint"
Are you kidding me! I have a hard time believing they have no scope to test with. They want to use my personal scope for testing??? Seems like a mickey mouse operation. Lets see... I purchase a new scope so they can do R&D.
I am very disappointed in the way this whole thing has been handled. This is the last Rigol product I will purchase.
Rigol, Send me one of the working scopes you have. and I will gladly send you this broken one for R&D.
In Hi-Res mode it use double amount of capture memory - why? Because in thiss mode it store 2 bytes for one (calculated) data point. (it is 16 bit)
It produce this using averaging (high res mode type of averaging)
No need more this OT.
first, what does averaging have to do with "hires"?
2nd, graticule of z series is 25pix per div, which yields 300x200 resolutuion (cropped graticule negative down, just zoom and count pixels)
no, count them (you can count them on your image too, it's easier than my image), unlesss there's a display setting i missed, and i doubt it, i searched the display menu last nite esp. because of screens like this (and also because i'm into video on pc, so i recognize lores instantly).
i understand what is said about hires mode, ie how it works (ie ...every pixels becomes a merger of surrounding pixels around it) but that has nothing to do with screen resolution in any way...
i would call this false advertising.
and i think anti-aliasing option in the scope has nothing to do with display, but with acquisition, i'm mentioning this because in video and games the anti-aliasing term means "to remove stair-stepping jaginess".