REVIEW - Rigol DS2072 - First Impressions of the DS2000 series from Rigol

[marmad]

Are you going to do a separate list of these bugs? So we could check if they are in the next FW uodate.

I don't think I would bother unless someone with a HW v.2 model (or A model) confirms each bug on their DSO. Some of the bugs might be hardware (v.1) related - and so would never get fixed by Rigol. Besides, EV, honestly, I'm not sure 300MHz is a good choice on hardware that wasn't designed for it.

I tested 300MHz option for about 3 weeks - and I had a few crashes - even one where the DSO started incorrectly believing it was a 2072 until I rebooted. Then today, after my trigger got screwed up and couldn't be corrected, I uninstalled it. Now at least if the DSO crashes, I will know that it's not because of the 300MHz option.

But if someone else wants to compile a list, I'm happy to tack it on at the beginning of the thread.

[PA0PBZ]

I don't think I would bother unless someone with a HW v.2 model (or A model) confirms each bug on their DSO.

I have a non-A version 2 hardware, can you point out one or more bugs that are easy reproduced? I can do some tests tomorrow.

[marmad]

I have a non-A version 2 hardware, can you point out one or more bugs that are easy reproduced? I can do some tests tomorrow.

Well, I don't know what caused my various crashes and strange behavior (which is one reason I wanted to uninstall that option) - but here are two other bugs reported that could be reproduced:

https://www.eevblog.com/forum/testgear/first-impressions-and-review-of-the-rigol-ds2072-ds2000-series-dso/msg356180/#msg356180

https://www.eevblog.com/forum/testgear/first-impressions-and-review-of-the-rigol-ds2072-ds2000-series-dso/msg353620/#msg353620

[EV]

I uninstalled BW 300M option. I can still get 1 ns time base from saved setup file with 1 ns time base. It goes away if I rotate horisontal scale button.

There is not much use with this option with so few sample points. There is about 2 dB difference at 300 MHz between DS2202 (-5 dB) and DS2302 (-3 dB). Both give trace from 300 MHz signal.

[mgrim]

But it seems to me you have a very simplified idea about how the captured samples end up as interpolated display. If vectors are ON, the display memory ALWAYS contains 1400 bytes (700 vectors) - it doesn't matter if the ADC captures 14M - or - 28 samples during the acquisition window. There are a WHOLE bunch of steps involved in arriving at those 1400 bytes - just one of which is the actual sin(x)/x or linear interpolation algorithm.

Hmm, that sounds interesting.

Could you please explain what the data in display memory actually is?

I've always wondered why there are 1400 bytes while the display is only 700 points wide, but wasn't able to come up with any verifiable scheme.

[marmad]

Could you please explain what the data in display memory actually is?

I've always wondered why there are 1400 bytes while the display is only 700 points wide, but wasn't able to come up with any verifiable scheme.

It's easier to visualize if you think of display memory as 700 'columns' of amplitude - instead of points. The DSO does peak-to-peak decimation, so the minimum and maximum amplitudes in a sample period are stored as vector endpoints for each column.

So, for example, if the DSO is decimating a 14k sample size, each column will contain the min. to max. amplitude found in each group of 20 samples.

[marmad]

I have similar problems when using the multi function knob. Also, it sometimes skips several entries or in my case causes the cursors to jump over the desired loactions. All in all, the knob is very unprecise in my experience.

I have very few problems with the multi-function knob skipping (and I have big hands) because of developing a specific way of using it when selecting things. Of course, when using it only for adjustment (like intensity), you can just rotate it normally - but if you want to experience very few skips when selecting, you need to develop a special method such as the following:

It has everything to do with the way you grip it (see image): my thumb is on the bottom edge of the knob front, while my index finger is on the top edge at the very back of the knob (snug against the case), with my hand supported by my 3 free fingers. The knob is turned precisely with opposing motions of the thumb and index finger (their positions don't change), and when the desired selection is reached, my grip tightens slightly with my index finger pushing slightly down and back against the case - while the thumb pushes slightly up and inward - essentially locking the knob from rotating during the click.

[Hydrawerk]

Even my DSOX2000 has a small multifunction knob. I wish it was bigger. At Owon and Tektronix they have big multi knobs. 

Even two big multipurpose knobs! 

[marmad]

Even my DSOX2000 has a small multifunction knob. I wish it was bigger. At Owon and Tektronix they have big multi knobs.

The knob size is fine - I wouldn't want to lose anything else to make room for a bigger one.

[marmad]

Just a tiny video for fun - showing how fast and easy it is to use the multifunction knob when you use the right grip.

This a totally unrehearsed, first-take video in which I type out "rigol ds2000 oscilloscope" on the software keyboard without selection errors in 50 seconds (although I could do it faster if I stopped laughing while shooting and actually gave some thought to each letter I needed next while selecting). I never attempted this before the video - and in fact, I've barely ever used the Rigol 'keyboard' (always using default names). Maybe this can be a challenge for who can get the fastest time (without errors)? 



EDIT: Just managed 38 seconds when I put some thought and concentration into it - so an average of 1.52 seconds for each of the 25 selections.

[EV]

After uninstalling BW 300M option BW has changed from 300 MHz to 240 MHz. Rise time has changed from 1.15 ns to 1.38 ns and over shoot has changed from 11.0 % to 8.5 %.

[AndersAnd]

I have similar problems when using the multi function knob. Also, it sometimes skips several entries or in my case causes the cursors to jump over the desired loactions. All in all, the knob is very unprecise in my experience.

I have very few problems with the multi-function knob skipping (and I have big hands) because of developing a specific way of using it when selecting things. Of course, when using it only for adjustment (like intensity), you can just rotate it normally - but if you want to experience very few skips when selecting, you need to develop a special method such as the following:

It has everything to do with the way you grip it (see image): my thumb is on the bottom edge of the knob front, while my index finger is on the top edge at the very back of the knob (snug against the case), with my hand supported by my 3 free fingers. The knob is turned precisely with opposing motions of the thumb and index finger (their positions don't change), and when the desired selection is reached, my grip tightens slightly with my index finger pushing slightly down and back against the case - while the thumb pushes slightly up and inward - essentially locking the knob from rotating during the click.

This got me thinking about when Steve Jobs said people were holding it wrong when customers complained about poor iPhone antenna signal. 



Maybe a new workshop mug to remind people to hold their scope knob correctly could come in handy.



And a new slogan idea for Dave's EEVblog T-shirts.

[PA0PBZ]

After uninstalling BW 300M option BW has changed from 300 MHz to 240 MHz. Rise time has changed from 1.15 ns to 1.38 ns and over shoot has changed from 11.0 % to 8.5 %.

You reversed the picture titles.

[AndersAnd]

After uninstalling BW 300M option BW has changed from 300 MHz to 240 MHz. Rise time has changed from 1.15 ns to 1.38 ns and over shoot has changed from 11.0 % to 8.5 %.

You reversed the picture titles.

Don't think so, the 300 MHz picture has faster rise time [1.148 ns] than the 200 MHz one [1.375 ns] as it should.

[PA0PBZ]

After uninstalling BW 300M option BW has changed from 300 MHz to 240 MHz. Rise time has changed from 1.15 ns to 1.38 ns and over shoot has changed from 11.0 % to 8.5 %.

You reversed the picture titles.

Don't think so, the 300 MHz picture has faster rise time [1.148 ns] than the 200 MHz one [1.375 ns] as it should.

After having a coffee and looking again you are right, it's just that the preview of the 200 Mhz one looks faster and I went wrong from there. 

[AndersAnd]

After uninstalling BW 300M option BW has changed from 300 MHz to 240 MHz. Rise time has changed from 1.15 ns to 1.38 ns and over shoot has changed from 11.0 % to 8.5 %.

You reversed the picture titles.

Don't think so, the 300 MHz picture has faster rise time [1.148 ns] than the 200 MHz one [1.375 ns] as it should.

After having a coffee and looking again you are right, it's just that the preview of the 200 Mhz one looks faster and I went wrong from there. 

Yeah that's the problem when one pic has a 1 ns timebase and the other pic has a 2 ns timebase.

[EV]

It must not be too easy! 

Yeah that's the problem when one pic has a 1 ns timebase and the other pic has a 2 ns timebase.

[Mark_O]

Just a tiny video for fun - showing how fast and easy it is to use the multifunction knob when you use the right grip.

This a totally unrehearsed, first-take video in which I type out "rigol ds2000 oscilloscope" on the software keyboard without selection errors in 50 seconds...

EDIT: Just managed 38 seconds when I put some thought and concentration into it - so an average of 1.52 seconds for each of the 25 selections.

Show off!     

[EV]

The next picture is from BATRONIX web site. There is told that with new measuring input stages the over shoot is below 5 %. The amplitude there is 5 mV when in my pictures it is 240 mV and the rise time of the pulse is < 70 ps.

After uninstalling BW 300M ..... and over shoot has changed from 11.0 % to 8.5 %.

[EV]

Here is rise time of scopes trigger out pulse. Its amplitude is 1.5 V and rise time about 1 ns probably. So the rise time of the pulse is much slower than the rise time of the pulse from TEK Type 284 generator.  The measured rise time is 1.5 ns and over shoot only 3.5 % with old measuring input stage.

[Carrington]

I am really interested to know the new values (and also the others, C and R without marking code) of the input stage. 
And also I want to know where are connected the following points (Red circles).

[AndersAnd]

The next picture is from BATRONIX web site. There is told that with new measuring input stages the over shoot is below 5 %. The amplitude there is 5 mV when in my pictures it is 240 mV and the rise time of the pulse is < 70 ps.

After uninstalling BW 300M ..... and over shoot has changed from 11.0 % to 8.5 %.

Here is rise time of scopes trigger out pulse. Its amplitude is 1.5 V and rise time about 1 ns probably. So the rise time of the pulse is much slower than the rise time of the pulse from TEK Type 284 generator.  The measured rise time is 1.5 ns and over shoot only 3.5 % with old measuring input stage.

What exactly are you talking about or think Batronix/Rigol are talking about when referring to new and old measuring input stages respectively.

I'm pretty sure when Batronix wrote "new measuring input stages", they were not referring to HW 2, but just referring to DS2000 in general and that it was written when the old HW 1 was all there was known. IIRC this has been on their website for a long time: http://www.batronix.com/shop/oscilloscopes/Rigol-DS2072.html
So when they wrote "new measuring input stages" they were not comparing HW 2 to HW 1, but just comparing DS2000 to older Rigol series scopes, maybe like DS1000E series which might have a bigger overshoot.

Batronix haven't even updated their website yet to mention anything a bout DS2000A series scopes.

[Carrington]

What exactly are you talking about or think Batronix/Rigol are talking about when referring to new and old measuring input stages respectively.

I'm pretty sure when Batronix wrote "new measuring input stages", they were not referring to HW 2, but just referring to DS2000 in general and that it was written when the old HW 1 was all there was known. IIRC this has been on their website for a long time: http://www.batronix.com/shop/oscilloscopes/Rigol-DS2072.html
So when they wrote "new measuring input stages" they were not comparing HW 2 to HW 1, but just comparing DS2000 to older Rigol series scopes, maybe like DS1000E series which might have a bigger overshoot.

Batronix haven't even updated their website yet to mention anything a bout DS2000A series scopes.

Yeap, that seems. Although I'm not 100% sure.

[AndersAnd]

Yeap, that seems. Although I'm not 100% sure.

I just checked "The Way Back Machine" to make sure, and this info was on Batronix' website already on October 13, 2012, long before HW 2 came along. Source: http://web.archive.org/web/20121013114141/http://www.batronix.com/shop/oscilloscopes/Rigol-DS2072.html

[EV]

Batronix haven't even updated their website yet to mention anything a bout DS2000A series scopes.

Maybe so, I don't know. Here is however the same picture with text "lower over shoot" under DS2000A web page:
http://www.rigol.com/prodserv/DS2000A/