Rigol DS1054Z vs Siglent SDS1202X-E

[tautech]

@borjam
Got your PM.

What concerns me is even while you're DC coupled the idle level is undetermined, it's midway neither Hi or Lo. 
How can that be ?

It's a two wire RS485 bus, which means it's half duplex. Devices are in high impedance mode when receving. In order to transmit, a device changes the port mode to transmission (which makes it reach the set the right idle mode), it transmits and after transmission it goes back to high impedance. That's why you see a 0 volt idle level.

Some devices can be a bit different. This one for example is a ModbusTCP-RS485 gateway and it doesn't assert the serial line before transmitting but it just begins with the first start bit. In another example I tried, using a different RS485 device, the line is "activated" in idle mode (so, the voltage goes high) and it waits for several ms before sending the first stop bit.

I am attaching a sample of that other device, this time captured on a Rigol DS1000Z. I tried this same device with the Siglent and it failed to decode the first byte successfully depending on the time base I configured.

In this case you see the idle value is around 2 V (positive).

OK, gotcha thanks to 2N3055. 
Is this from the 8th still true:

I have been trying with a RS485 bus, capturing Modbus packets at 9600 bps. And packets for which all the bytes decoded successfully at 10 ms/div had some errors when capturing at 50 or 100 ms/div.

And it's a timebase specific thing ?
Which implies it's doing it wrong in the old ROLL mode settings, something that was supposed to be fixed in the X (not X-E) series but this is a little different.
Factory is finished for today but I'll have some time to have a bash with my test board and see if I can duplicate it in the morning and report it before they get to work. 

[borjam]

Is this from the 8th still true:

I have been trying with a RS485 bus, capturing Modbus packets at 9600 bps. And packets for which all the bytes decoded successfully at 10 ms/div had some errors when capturing at 50 or 100 ms/div.

And it's a timebase specific thing ?
Which implies it's doing it wrong in the old ROLL mode settings, something that was supposed to be fixed in the X (not X-E) series but this is a little different.
Factory is finished for today but I'll have some time to have a bash with my test board and see if I can duplicate it in the morning and report it before they get to work. 

I disabled the roll mode of course.

Anyway, I have a full capture (14 MB file) and setup.xml file. You can send them to Siglent so that they can determine wether it's a bug or not.

As a matter of fact I purchased my scope from Batronix, maybe I should let them know as well. But given that you are already following the issue here it might be redundant. No matter where you distribute them I guess you are interested on Siglent products working properly.

Maybe even Siglent is reading. Hello?

[tautech]

Is this from the 8th still true:

I have been trying with a RS485 bus, capturing Modbus packets at 9600 bps. And packets for which all the bytes decoded successfully at 10 ms/div had some errors when capturing at 50 or 100 ms/div.

And it's a timebase specific thing ?
Which implies it's doing it wrong in the old ROLL mode settings, something that was supposed to be fixed in the X (not X-E) series but this is a little different.
Factory is finished for today but I'll have some time to have a bash with my test board and see if I can duplicate it in the morning and report it before they get to work. 

I disabled the roll mode of course.

It's disabled by default in slow timebase settings while in Decode.

Anyway, I have a full capture (14 MB file) and setup.xml file. You can send them to Siglent so that they can determine wether it's a bug or not.

Thanks, won't need it.

As a matter of fact I purchased my scope from Batronix, maybe I should let them know as well. But given that you are already following the issue here it might be redundant. No matter where you distribute them I guess you are interested on Siglent products working properly.

Exactly.
We try, some might call us very trying. 

Don't discount another round of FW updates for the X-E, there's still a few minor issues I've seen and reported.

Maybe even Siglent is reading. Hello?

7.30pm in Shenzhen, not likely and 11.30 here............bed.

[rf-loop]

At this time without extra work I do not have available good test signal but using signal generator... 4600Hz square 15 cycles and cycle period 3s. This is same as 9600 baud 1 start, 8bit, 1 stop, noparity  (data value 0x55/ASCII U/ binary 01010101)

Trigger start bit.

No problems using 100ms/div or other more slow settings.

Here 2s/div
signal is 3* 0x55   repeating every 3 second.
1 image
First without zoom so that it can see every message is without problems. (if there is problems this decode line show red marks)
2. image
Then scope still running and now zoomed for look one 3 byte "message"

Also tested with same signal 5s/div. No problem.

3. image
Also 10s/div, no problem.

More slow testing... not time to do more.
Of course this kind of signal is not at all good for testing but still it show something.
Also with slow time bases every burst is decoded ok when look these with zoom and of course also data table show it.

Data table have some bug. If there is long message and I have zoomed part of it. Data table can of course scroll to show what ever byte in message but there is, imho, Bug. Every time scope start new acquisition it jump back to show beginning of message / least using these slow time bases. Not tested more.

[borjam]

Just adding some more data points.

I have been trying to decode the same signal at different time base settings.

At 1 ms/div and 2 ms/div it decodes fine.

At 5 ms/div and so forth it fails on the first byte. I have included the screenshots below.

The decode is configured as UART with the following parameters:

Threshold: -1V
Baud: 9600
Data length: 8 bit
Parity: None
Stop bit: 1
Idle level: High
Bit order: LSB
Link to trigger: Decode 1

Trigger set up:
Type: Serial
Protocol: UART
Signal: Threshold: -1 V
Trigger setting -> Source type: TX
Condition: Start

Bus configure->Baud: 9600
Bus configure->Data Length: 8
Bus condifure->Parity check: None
Bus configure->Stop bit: 1
Bus configure->Idle level: High
Bus configure->Bit order: LSB



The files are:

1 ms/div
2 ms/div
5 ms/div
5 ms/div (previous capture zooming in on a packet)
10 ms/div
10 ms/div (previous capture zooming in on a packet)
20 ms/div
20 ms/div (previous capture zooming in on a packet)
100 ms/div
and 100 ms/div zoomed in on different parts of the capture.

[Electric2000]

How does the GDS-1054B compare to these two models?

[nctnico]

How does the GDS-1054B compare to these two models?

More mature firmware but no decoding. BTW lots of UI improvements SDS1202X-E users are asking for are already in the recent GW Instek scopes.

[Fungus]

How does the GDS-1054B compare to these two models?

Nice to use but low bandwidth,, no serial decoders not hackable, ugly, not great bang-per-buck.

[cbc02009]

Hi all,

was wondering if there has been any major changes in this comparison in the last couple of months. I'm deciding between these two and the micsig TO1104 which is now on sale for ~$80 off. Thought it might be better to use this thread than starting an entirely new one. Any advice would be greatly appreciated. Main use case is school projects and hobby stuff using the MSP430 and the atmega2560.

[trys]

cbc02009

I've got the Rigol, just bought it. I'm delighted with it.

In the last month I've only use two channels.

The Siglent one comes with decoding built in. The Rigol does not, unless you want to take the moral dilemma of stealing this additional functionality by unlocking this is a few seconds. They sell this functionality.

The Siglent has had a hardware issue with probe compensation at 10x. New units that have been manufactured (we are told on here anyhow) have been fixed. The concern is that distributors will still have older stock before the fix.

The shading gradients of the Siglent appears better on paper.

Having said all that, as I said, I recently bought the Rigol DS1054Z, and I'm really delighted with it.

As far as the extra two channels, well the question is whether you think you can really concentrate on more than two things at once or not realistically. It's probably a "nice to have".

I'm glad I have those extra two, but it's not a deal breaker.

Either scope will do you well.

[bd139]

4 traces is VERY useful: https://www.eevblog.com/forum/repair/tektronix-475-repair-assistance/msg1330121/#msg1330121

[tautech]

Hi all,

was wondering if there has been any major changes in this comparison in the last couple of months. I'm deciding between these two and the micsig TO1104 which is now on sale for ~$80 off. Thought it might be better to use this thread than starting an entirely new one. Any advice would be greatly appreciated. Main use case is school projects and hobby stuff using the MSP430 and the atmega2560.

Welcome to the forum.

If you can hang on until the 4 ch X-E is available it will clean them all up.
Watch for a vid Dave will do on them very soon as they will be released in the next few days.
https://www.eevblog.com/forum/testgear/siglent-sds1204x-e-released-for-domestic-markets-in-china/

The HW issue that trys mentions affects the older 2 ch models and will be corrected in the 4 ch versions before they get to market.

[kahe40]

deciding between these two and the micsig TO1104

I have both,
the Rigol is Desktop, nice UserInterface with Knobs (OldSchool), but 5or6 years old technology
the Migsig is Tablet, portable, big screen (4:3), WLAN and optional HDMI (for school?)
handling is faster, only some taps (or mouse) and you are done...
and it is far less noisy with far better FFT and faster X-Y

to decide, see the Micsig-Thread here and maybe youtube

[kirill_ka]

was wondering if there has been any major changes in this comparison in the last couple of months. I'm deciding between these two and the micsig TO1104 which is now on sale for ~$80 off. Thought it might be better to use this thread than starting an entirely new one. Any advice would be greatly appreciated. Main use case is school projects and hobby stuff using the MSP430 and the atmega2560.

Micsig allows for a different work style. You test something, then take scope to the sofa to review waveforms and videos 

[nctnico]

was wondering if there has been any major changes in this comparison in the last couple of months. I'm deciding between these two and the micsig TO1104 which is now on sale for ~$80 off. Thought it might be better to use this thread than starting an entirely new one. Any advice would be greatly appreciated. Main use case is school projects and hobby stuff using the MSP430 and the atmega2560.

Micsig allows for a different work style. You test something, then take scope to the sofa to review waveforms and videos 

I agree and the battery operation makes the TO1104 way more portable. I have a TO1104 myself and the small formfactor and battery make it easy to just pull it out and place it somewhere for a quick measurement. Besides that the TO1104 has no bugs that I'm aware off. Everything just works.

[cbc02009]

Huh, okay. So it sounds like I should hold off for a bit because the new products will be coming out shortly. Thank you all for your advice. I might just go with a cheap usb one until then, as I don't currently need a great amount of accuracy.

[Doofus]

Like many others I'm trying to decide between the 1054z and Siglent's 1202xe. I'm not willing to pay the extra bucks for the new 1204xe with first generation firmware. My interests mostly involve audio and power supplies with  occasional dabbling in arduino, esp8266 etc. I am curious about the relative performance with FFTs. Perusal of these blogs leads me to believe the Siglent 1202xe is the better performer in this area. Since they both use 8 bit A/D, is the difference due to Siglent's newer more powerful SOC? Is the Rigol limited by its processing hardware or is it possible that a firmware change could close the gap? What is the nature of the FFT difference today and is it likely to change? 4 channels is not a trump card for me nor is a 200Mhz bw. I also acknowledge Siglent's compensation vs attention problem but don't think it'll be a show stopper for me. Thanks for any advice.

[ebastler]

Micsig allows for a different work style. You test something, then take scope to the sofa to review waveforms and videos 

Remember to unplug probes first... 

[Fungus]

I am curious about the relative performance with FFTs. Perusal of these blogs leads me to believe the Siglent 1202xe is the better performer in this area. Since they both use 8 bit A/

For Audio FFTs a decent sound card will destroy both of them (16 bits or more in the samples...)

You can also process the data from a 'scope on a PC, all you need is an Ethernet cable (I assume the Siglent can do this, I know the Rigol can). This way you're not limited to what the 'scope can do.

https://sigrok.org/

[tautech]

Like many others I'm trying to decide between the 1054z and Siglent's 1202xe. I'm not willing to pay the extra bucks for the new 1204xe with first generation firmware. My interests mostly involve audio and power supplies with  occasional dabbling in arduino, esp8266 etc. I am curious about the relative performance with FFTs. Perusal of these blogs leads me to believe the Siglent 1202xe is the better performer in this area. Since they both use 8 bit A/D, is the difference due to Siglent's newer more powerful SOC? Is the Rigol limited by its processing hardware or is it possible that a firmware change could close the gap? What is the nature of the FFT difference today and is it likely to change? 4 channels is not a trump card for me nor is a 200Mhz bw. I also acknowledge Siglent's compensation vs attention problem but don't think it'll be a show stopper for me. Thanks for any advice.

Welcome to the forum

Yep the faster processor is responsible for the great (for entry level) FFT performance.
SN#'s after BBD do not have the compensation issue.

[trys]

Doofus,

Be aware that tautech is associated with Siglent, as nice as he is, so bear this in mind with responses about comparing to other manufacturers.

As far as Audio is considered, I've pretty amazed at how useful Audacity is using the "Plot Spectrum" function (which is effectively what you're seeing with FFT). This is just using a £1 USB Sound Card dongle, and the free open source Audacity software.

Also, as far as compensation issues only affecting "old" Siglent 1202xe, that is not entirely true. We are led to believe that due to shipping times, and general stock control that there are enough stocks held globally by distributors and resellers that you cannot guarantee at this stage whether you will get one with the probe compensation hardware fault or not.

As far as Audio is concerned, JohnAudioTech in Youtube does an excellent job using FFT on his Rigol scope.

Trys

[nctnico]

And let's not forget about Digilent's 'Analog Discovery' which sits somewhere between a sound card and an oscilloscope.

[Fungus]

And let's not forget about Digilent's 'Analog Discovery' which sits somewhere between a sound card and an oscilloscope.

And is excellent for Audio analysis thanks to a 14-bit ADC.

[Old Printer]

And let's not forget about Digilent's 'Analog Discovery' which sits somewhere between a sound card and an oscilloscope.

I have one and really like it as a learning tool, it is packed full of functions. I still feel the need for a "real" DSO, but I am not in a rush and can wait to see how this 4 channel market progresses. The Analog Discovery has 2 main drawbacks as I see it, the 20mhz bandwidth limit, and the price. At $279 it is pretty close to the Rigol 1054Z at $330 (w/discount). There is a lot of first hand info available on it as an audio tool, particularly on YT.  Dave

[Doofus]

I hadn't heard of the Analog Discovery before. It looks like it could be an economical ($300 or so) alternative for a low frequency analyzer. Interesting as an extra piece of gear but I'd still be looking for a more user friendly scope. Having an AWG and logic analysis capabilities as well as a programmable PS gives it quite a bit of Moxie.