Choosing between entry-level 12-bit DSOs

[tautech]

This is very, very important point...

If you only look superficially and your only criteria is color, then, really, there is no difference....
And you should go with color that you prefer.
No argument there.

Or if you look at two models and they both do what you need, but one is cheaper, that could also be a reason to buy it.

If you can get an SDS814 shipped to Australia for AUD$660, please let me know!

Last I heard Appvision was still waiting for stock, as we are.

[2N3055]

This is very, very important point...

If you only look superficially and your only criteria is color, then, really, there is no difference....
And you should go with color that you prefer.
No argument there.

Or if you look at two models in detail and they both do what you need, but one is significantly cheaper and happens to be a colour that you prefer, that could also be a reason to buy it.

Although, if you can get an SDS814 shipped to Australia for AUD$660, please let me know and I'll definitely consider it!

¸

You didn't explain all of that in original post.

But my points are:
- these two scopes are very different. Only superficially they seem similar.
- each person decides what their priorities are in terms of device capabilities.
- if person doesn't plan to use scope for anything but very basic squiggles on the screen then it doesn't matter which one you buy. In that case you can go with cheapest option you can buy...

[Electro Fan]

On the other hand, I would like to re-iterate that I consider the Rigol UI easier to get started with. It typically has all relevant settings for a given mode (measurement, decoder, trigger...) in one large dialog. In contrast, Siglent's UI often relies on nested menus which you need to dig through to find and set all relevant parameters. Again, this may be an important advantage for new or sporadic users, while others will find that they get comfortable with the Siglent UI very quickly.

I think I have seen this sentiment more than once (not just from ebastler). Let me pose the question this way to see if anyone has further input on the respective UI's:

For someone who has not used a DSO before, who does not yet know all of the possibilities - who doesn't know how much he or she doesn't know! - would the UI of the Rigol (or of the Siglent) be more likely to help this person find / figure out these possibilities? Or does the person really need to learn what capabilities to look for, before trying to find them in the UI?

Not sure how clearly I have asked the above, but I don't know how to clarify it. Have I mentioned that I am operating from a wealth of ignorance?

It's a reasonable question to ask and people who own or have owned both a Rigol and a Siglent can best answer your question.

As just a Rigol user but a Siglent fan I think the answer is going to be that you are in for a mostly fun but occasionally frustrating learning curve either way.  The frustrating part will mostly be driven by trial and error vs RTFM, plus maybe occasionally encountering a bug but not knowing you hit a bug; bugs don't happen often but both Rigol and Siglent have them, and sometimes they acknowledge and respond to them and sometimes they don't right away.  Overall, the learning curves are likely to be more similar than different. 

To make metaphor, if you have been speaking English and you want to learn French or Spanish there is going to be a learning curve.  At the end of the day you should probably consider - based on your research including feedback from other travelers and your own criteria - whether you want to visit France or Spain.  I think it's good to enjoy the pre-buying research phase as it offers a chance to learn and enjoy and then you will have another chance to learn and enjoy still more once you get the oscilloscope.

[Harrow]

You didn't explain all of that in original post.

But my points are:
- these two scopes are very different. Only superficially they seem similar.
- each person decides what their priorities are in terms of device capabilities.
- if person doesn't plan to use scope for anything but very basic squiggles on the screen then it doesn't matter which one you buy. In that case you can go with cheapest option you can buy...

I did, but you had to read all of the post, not just the first half.

If you are talking about capabilities between the two, you also need to talk about cost. For example, to get bode plots with the SDS814 you also need to buy the wave generator, which makes the overall cost more than double for me, so that's the kind of comparison you need to be making. If we want to ignore cost, I'm sure I can find something that makes the SDS800 look like a toy.

[tautech]

If you are talking about capabilities between the two, you also need to talk about cost. For example. to get bode plots with the SDS814 you also need to buy a wave generator, which makes the overall cost more than double for me, so that's the kind of comparison you need to be making.

FTFY.
SAG1021I for $165 does not double cost.

[Harrow]

If you are talking about capabilities between the two, you also need to talk about cost. For example. to get bode plots with the SDS814 you also need to buy a wave generator, which makes the overall cost more than double for me, so that's the kind of comparison you need to be making.

FTFY.
SAG1021I for $165 does not double cost.

Cost of the SDS814 + the waveform generator, (do I also need the software licence for another US$115?), shipped to me and taking into account the exchange rate is near enough to double what I've paid for the Rigol. (I didn't mean it doubles the cost of the Siglent). Might well be a different story once it's available in Australia and other cheaper channels, but that doesn't help me now. I just wanted a basic scope for minimal cost so I can decide exactly what I need in a higher-end scope in about a year's time, so the Rigol ticks that box for me at the moment.

I'm wondering how many sales Rigol managed to get by being first to market....probably quite a lot!

[tautech]

If you are talking about capabilities between the two, you also need to talk about cost. For example. to get bode plots with the SDS814 you also need to buy a wave generator, which makes the overall cost more than double for me, so that's the kind of comparison you need to be making.

FTFY.
SAG1021I for $165 does not double cost.

Cost of the SDS814 + the waveform generator (do I also need the software licence?), ........

Not for Bode plot, only for FG functionality if required.

[Harrow]

Excellent advice! Every time I think I am starting to lean in one direction, someone comes along and talks about their good experience with the other one. I look forward to hearing about your experience with the DHO804.

If you can wait a couple of weeks, I'll definitely post my experience. For now, I think I'll bow out of the discussion, lol.

[vk6zgo]

I did a little reading on Bode plots just a bit ago - I now see where they could be very useful in some circumstances. Am I correct in thinking that the "magic" of the DSO Bode plot is that it gives you the whole plot across the frequency range automatically? As opposed to measuring amplitude and phase shift at, say, a dozen discrete points along the frequency range, and creating a rough graph? (I may have just revealed how little I understood of what I read ... !)

Essentially yes.

While everyone refers to Bode plot also consider it more correctly as Frequency Response Analysis. (FRA)
Implications can be fast or slow in that each each measurement point is measured several times and averaged before that single frequency is plotted.
While we might do a wide sweep initially it is more normal to control the range of the frequencies of interest and we have full control to do this within the menu.

Deep investigations of its capabilities with the previous X-E DSO's are here:
https://www.eevblog.com/forum/testgear/siglent-sds1x04x-e-bodeplot-ii-(sfra)-features-and-testing-(coming)/

An example testing a passive bandpass filter:
https://www.eevblog.com/forum/testgear/siglent-sds1204x-e-released-for-domestic-markets-in-china/msg1435854/#msg1435854

Later in Reply 550 we examine both stages of the same filter.

Yes, when I learnt about "Bode plots" in the 1980s, it was as a purely theoretical concept.
We were given the transfer function of frequency-v-amplitude or frequency-v- phase & required to draw the response curves.
They didn't resemble a real life frequency response curves very closely, having sharp "break points".

In real life, we measured "swept frequency response" (normally amplitude, unless we had a VNA).
Latterly, the term "Bode plot" seems to have been enlarged to include these measurements.
Maybe because it gives EEs a sort of "woo-woo" factor as compared to the "great unwashed".

[awakephd]

Seriously, look at MicSig's TO1004 as well. This is a mature, reliable piece of equipment which has been out there for a while already and the display is so much bigger which makes it easier to use.

I looked at it ... the cheapest price I'm seeing for this model is $629, which puts it about 150% of the price of the Rigol and Siglent models I am considering.

[rpro]

For someone who has not used a DSO before, who does not yet know all of the possibilities - who doesn't know how much he or she doesn't know! - would the UI of the Rigol (or of the Siglent) be more likely to help this person find / figure out these possibilities? Or does the person really need to learn what capabilities to look for, before trying to find them in the UI?

There are some aspects of the Rigol DHO800 that I like and use all the time, like displaying multiple windows, for which the HDMI output to a bigger screen makes a lot of sense. Its XY functionality is also well featured, and the scope fan is not as loud. While the update rate of the FFT is relatively fast, its features could be vastly improved, and I am still hoping that Rigol will see the light and invest the few hours of development work needed to bring it up to par with the competition. (In the meantime, thanks in part to its fast update rate, it is quite easy (but far from ideal of course!) to quickly fetch FFT sample traces with a PC for further processing.)   

[awakephd]

Excellent advice! Every time I think I am starting to lean in one direction, someone comes along and talks about their good experience with the other one. I look forward to hearing about your experience with the DHO804.

If you can wait a couple of weeks, I'll definitely post my experience. For now, I think I'll bow out of the discussion, lol.

Absolutely. My timeline for purchase is two months out. Oddly enough, that roughly coincides with Father's Day here in the US ... surely just a random coincidence. Ahem.

By then, hopefully the supply for the Siglent is stronger - I've been seeing "out of stock" for the SDS804 on some of the places I've looked. And who knows - maybe by then there will be a huge sale on one or the other ...

[Harrow]

There are some aspects of the Rigol DHO800 that I like and use all the time, like displaying multiple windows, for which the HDMI output to a bigger screen makes a lot of sense. Its XY functionality is also well featured, and the scope fan is not as loud. While the update rate of the FFT is relatively fast, its features could be vastly improved, and I am still hoping that Rigol will see the light and invest the few hours of development work needed to bring it up to par with the competition. (In the meantime, thanks in part to its fast update rate, it is quite easy (but far from ideal of course!) to quickly fetch FFT sample traces with a PC for further processing.)   

That looks great! The combination of dockable windows and HDMI output to a larger screen was a part of my decision. I'm really looking forward to it after seeing those screenshots.

[tautech]

I did a little reading on Bode plots just a bit ago - I now see where they could be very useful in some circumstances. Am I correct in thinking that the "magic" of the DSO Bode plot is that it gives you the whole plot across the frequency range automatically? As opposed to measuring amplitude and phase shift at, say, a dozen discrete points along the frequency range, and creating a rough graph? (I may have just revealed how little I understood of what I read ... !)

Essentially yes.

While everyone refers to Bode plot also consider it more correctly as Frequency Response Analysis. (FRA)
Implications can be fast or slow in that each each measurement point is measured several times and averaged before that single frequency is plotted.
While we might do a wide sweep initially it is more normal to control the range of the frequencies of interest and we have full control to do this within the menu.

Deep investigations of its capabilities with the previous X-E DSO's are here:
https://www.eevblog.com/forum/testgear/siglent-sds1x04x-e-bodeplot-ii-(sfra)-features-and-testing-(coming)/

An example testing a passive bandpass filter:
https://www.eevblog.com/forum/testgear/siglent-sds1204x-e-released-for-domestic-markets-in-china/msg1435854/#msg1435854

Later in Reply 550 we examine both stages of the same filter.

Yes, when I learnt about "Bode plots" in the 1980s, it was as a purely theoretical concept.
We were given the transfer function of frequency-v-amplitude or frequency-v- phase & required to draw the response curves.
They didn't resemble a real life frequency response curves very closely, having sharp "break points".

In real life, we measured "swept frequency response" (normally amplitude, unless we had a VNA).
Latterly, the term "Bode plot" seems to have been enlarged to include these measurements.
Maybe because it gives EEs a sort of "woo-woo" factor as compared to the "great unwashed".

IMO it's best referred to more accurately as FRA.
Which in itself makes more sense and just is the frequency response/attenuation of a circuit/device.

We can do this easy with an analyzer with TG into the high frequency bands and a FRA capable scope is better suited to LF work to the 120 MHz capability of Siglent DSO's.
Some simple FRA can also be done with a TG equipped analyzer and RLB where results similar to a single port VNA S11 measurements can be obtained.
Only hope we get the chance for a propper meet up next time we visit WA Bryan.

[Fungus]

afaik, FFT on DHO800/900 is so much better already than DS1000Z

It's orders of magnitude better, it also has tables of the peaks, etc.

It's also fast, much faster than the Siglent, AFAIK.

By a certain age, pretty much all engineers prefer an easier-to-read display

Rigol wins there - the text is really, really nice.

If you need a VESA mount and HDMI output, then the Rigol wins. The shallower footprint is also cute.

The UI of the Rigol is better. The windowing system is also a big feature (IMHO) that Siglent doesn't have.

If you live and die by your FFT then it's enough to swing the decision in favor of the Siglent. If you want Bode plot then you obviously only have one choice.

If not... I don't think you can say one is "best".

[KungFuJosh]

If you need a VESA mount and HDMI output, then the Rigol wins. The shallower footprint is also cute.

The UI of the Rigol is better. The windowing system is also a big feature (IMHO) that Siglent doesn't have.

That's your opinion, and it's valid. OTOH, I personally hate the look of the general UI on the Rigol. To each their own.

I do think the windowing is a cool feature, but it's not something I personally need. Siglent will likely add something like it eventually if enough people request it.

[ebastler]

The UI of the Rigol is better. The windowing system is also a big feature (IMHO) that Siglent doesn't have.

As mentioned before, I do think that the UI is more beginner-friendly. I am not so excited about the window system on the small screen. ("Small" as in "limited number of pixels", not "small diagonal"; so connecting an external monitor will not change this.)

When I had the DHO1000, which comes with a larger and higher-resolution screen, I felt that the usefulness of the windows was borderline, because they waste so much screen space for frames and titles. Those frames still take up the same number of pixels on the smaller DHO800 screen. Hence they consume an even larger relative share of the screen real estate, leaving rather small areas for the actual traces/FFT spectra/results tables.

Siglent's UI may look a bit drab, but uses less screen space for frames and decorations. It can display more ancillary information (e.g. probe attentuation, trigger counter, details for each math function) while still keeping the trace display area a bit larger than on the Rigol.

[eTobey]

I had the DHO814, and i was very frustrated:
- At least one crash a day. (gotta love android)
- Waveforms dissappear when scrolling around.
- That UI was rather annoying, and wasted a lot of display area
- settings were not saved after restart.
- Noise from the powersupply
- Ultra acquire is ultra useless (at least for infrequent signals with bigger interval)
- Only 16 characters as filename to save
- FFT cant measure/see much there
- ... and the list goes on

That vesa mount is kind of a fail, as the airflow would be blocked.


But the probes were of quite a good quality, judging from their look and feel.

[2N3055]

There are some aspects of the Rigol DHO800 that I like and use all the time, like displaying multiple windows, for which the HDMI output to a bigger screen makes a lot of sense. Its XY functionality is also well featured, and the scope fan is not as loud. While the update rate of the FFT is relatively fast, its features could be vastly improved, and I am still hoping that Rigol will see the light and invest the few hours of development work needed to bring it up to par with the competition. (In the meantime, thanks in part to its fast update rate, it is quite easy (but far from ideal of course!) to quickly fetch FFT sample traces with a PC for further processing.)   

That looks great! The combination of dockable windows and HDMI output to a larger screen was a part of my decision. I'm really looking forward to it after seeing those screenshots.

Just so you know:
Make note that window titles are scrambled and partial.
Going to a bigger screen won't give you better resolution, it will rescale current screen. It won't behave like you would expect if you connect second screen on a PC.
What you see on these screenshots is exactly how it will look, just bigger.
If that is what you expect than fine.

As for fixing FFT, it has been in this half cooked state for years now and I wouldn't hold my breath. Nor for any other fixes, to that matters. They sometimes fix some things, but priority and timing seems stochastic. And they take they sweet time.
But sometimes bugs are in parts of software you don't use so it doesn't matter. Sometimes for bugs to show it takes particular workflow so some people have crashes all the time and some almost never.

You will see and decide for yourself.

[tggzzz]

Yes, when I learnt about "Bode plots" in the 1980s, it was as a purely theoretical concept.
We were given the transfer function of frequency-v-amplitude or frequency-v- phase & required to draw the response curves.
They didn't resemble a real life frequency response curves very closely, having sharp "break points".

In real life, we measured "swept frequency response" (normally amplitude, unless we had a VNA).
Latterly, the term "Bode plot" seems to have been enlarged to include these measurements.
Maybe because it gives EEs a sort of "woo-woo" factor as compared to the "great unwashed".

Bode plots have always been log-frequency vs log-amplitude (and phase). Why? Because (for LP filters) the double-log graphs turn an 1/x curve into a straight line, and >> the corner frequency the falloff is 1/f, i.e. 10dB/decade.

The straight lines with a "sharp" corner are - and always have been - simply a convenient approximation, useful for drawing and thinking about a filter's overall characteristic.

There are many many many other useful approximations in engineering that aid thinking about cause and effect.

[tggzzz]

How about someone who has used several scopes commenting on some other relative usability issues, e.g.

• GUI responsiveness. One scope I played with for a short time had an appalling lag between changing the Y offset and the trace on the display moving
• triggering. I'm not thinking about fancy triggers, but how well or poorly they capture waveforms near the scope's performance limit. Low voltages, high frequencies, various types of noise

[shapirus]

There are some aspects of the Rigol DHO800 that I like and use all the time, like displaying multiple windows

BTW, Rigol cannot (or I don't know how to make it) render the math waveform in the main waveform window, which defeats half of the purpose: you can't overlay traces on the same scale and you lose half of the screen height by placing the windows one above the other if you want to observe raw and math input aligned horizontally.

It also cannot use math result waveform as one or more of the X-Y sources. It cannot use math result as a source for another math operation. So the usability of math is quite limited.

Is all of this also the case with Siglent? Or it's a general limitation? If so, is it a limitation in this class only or it applies to all digital scopes?

[shapirus]

afaik, FFT on DHO800/900 is so much better already than DS1000Z

It's orders of magnitude better, it also has tables of the peaks, etc.

But it cannot, for whatever reason, display the peak values on top of the peaks themselves, right in the FFT window, forcing the user to constantly move the eye from the diagram to the table and back and match the visual peaks with rows in the table by looking for each peak individually. Not to mention that the user has to waste a significant section of the screen for the window with the peaks table.

That's a really big downside and yet another Rigol's UI disaster. I'm not comparing it with previous Rigol models, just evaluating it on its own.

[shapirus]

• GUI responsiveness. One scope I played with for a short time had an appalling lag between changing the Y offset and the trace on the display moving

Rigol DHO800 sucks in this respect. My definition of "sucks": the waveform update freezes and remains stopped while the vertical (or horizontal) offset encoder is being turned. Analog scopes do not suck: you can turn the offset dials for as long as you want, and the trace(s) will continue to update in real time as if nothing is happening. Do any digital scopes behave this way too?

After the offset encoder stops turning, the waveform update/rendering on DHO800 resumes in what feels to be about 300-400 ms.

p.s. I may have misunderstood the meaning of your question. If you ask how quickly the screen content moves when an offset encoder is turned, then it happens nearly instantly, so in this particular function DHO800 does not suck. With one exception: when you scroll along a large memory buffer with the zoom window turned on, then it becomes somewhat slower (yet still acceptable even to my taste), and sometimes it's glitching when the offset is at the edges of the memory buffer.

[Mechatrommer]

There are some aspects of the Rigol DHO800 that I like and use all the time, like displaying multiple windows

BTW, Rigol cannot (or I don't know how to make it) render the math waveform in the main waveform window, which defeats half of the purpose:

good point, i just tried it myself, overlayed display sometime preferable, sometime i wonder the rigol GUI developer is a kid clueless about real life usage of dso... maybe posting in rigol dho800 bug/wishlist if good idea to make rigol aware of this issue..