MSO5000 Bode Plot Capability: Is it Good Enough? [Many tips about a 1st scope]

[Fungus]

So, if I stimulate the circuit with an external WG, the AD2 will bodeplot its response? Thanks.

No, Bode plot and impedance analysis works by controlling generator and scope in synchronization.  AD2 has internal AWG and uses that one...No support for external AWG.

Weird. My copy of the manual says the generator can be external. You might know that if you owned an AD2...



PS: Can your oscilloscope do this?

[egonotto]

Hello,

now the Bode plot with the LC oscillating circuit with lower C.

The Network Analyser of AD2 goes with the new Waveforms till 25 MHz

Best regard
egonotto

[JeremyC]

FWIW: Here's a screenshot taken with my AD2 with nothing connected to the input. 5 or 10 mV is about as low as it usefully goes without 50 Ohm terminated stuff (yes, it has a real 50 Ohm termination).

Fungus, the "Discovery BNC" board doesn't have 50 Ohm input termination. The JP4 and JP5 jumpers are for AWG output.

[balnazzar]

Also, can you confirm that the software is complete, functional, and overall better than the sw that comes generally with bench scopes?

As I said earlier, you can download and try the software for free.

The problem is interfacing the soundcard with the probes (I'm trying to understand how to). I installed the software, but I should do something real with it.

[balnazzar]

Hello,

I tried a Bode plot with an LC oscillating circuit. The signal is severely disturbed, but it still worked to some extent. Enclosed the circuit (drawn with the mouse) and the Bode plot, the signals measured with the AD2 and a signal measured with the RTA4000.

Waveforms can now run the function generator with 25 MHz, but there is a warning. This means that the network analyzer now goes up to 25 MHz.

Best regards
egonotto

Thanks! This was very useful information.

Why is the signal from the LC oscillator so disturbed? I mean, it seems to be so even with the other instrument (presumably a more expensive dedicated NA, as far as I understand).

[balnazzar]

Limit will be 10 MHz because that is the limit of internal waveform generator. Scope bandwidth is better, up to 30 MHz.

So, if I stimulate the circuit with an external WG, the AD2 will bodeplot its response? Thanks.

No, Bode plot and impedance analysis works by controlling generator and scope in synchronization.  AD2 has internal AWG and uses that one...No support for external AWG.

I still don't understand why the integrated WG and NA can get to 25 MHz (not bad!) but they advertise the WG to be capable of just 10 MHz...

[balnazzar]

Weird. My copy of the manual says the generator can be external. You might know that if you owned an AD2...

That's even better news! 

[balnazzar]

Folks, I'm very appreciative with all of you that took time to answer my questions (admittedly ill-posed). Even more useful is the discussion among more informed contributors, regardless of my questions.

I think this thread could be an useful resource for those who'll want to pick up a first scope with limited budged, and it's also (afaik) the first thread on eevblog that discusses the capabilities of the AD2 by providing examples and underlining little but important things that are overlooked in the reviews.

[JeremyC]

balnazzar, few months ago "The Signal Path" did review the ADP3450 from Digilent. It's 4 channel and more advance instrument, but software is the same. I suggest you watch the video, you may want to start at minute 13:00.

 

[baldurn]

Yep, our most popular budget conscious pairing, SDS1104X-E and SDG1032X and those with a little more go for SDG2042X that if both are 'improved' pushes out to the 120 MHz max of Siglent Bode plot capability.

I just bought a SDS1104X-E + SDG1032X for our local maker space. I got higher end equipment myself but this combo seems excellent for the beginner, for teaching and really for most. We can do almost everything up to RF work at HAM level. Lots of talk about the intuitiveness of instruments in this thread but what about the complete solution? Get those two, connect with the supplied USB cable and DONE. Start focusing on the actual electronics you want to do instead of the instruments.

I don't really get the budget constraints. The MSO5074 appears to be €799 at eleshop.eu. The SDS1104X-E is €429 and SDG1032X is €289 total €718 so why would it be out of budget?

Down the road you will be buying new toys. Do not think what you buy today, no matter the budget, will be the last thing you buy or upgrade :-). But in reality this is a very strong offer that many will never outgrow.

[Fungus]

FWIW: Here's a screenshot taken with my AD2 with nothing connected to the input. 5 or 10 mV is about as low as it usefully goes without 50 Ohm terminated stuff (yes, it has a real 50 Ohm termination).

Fungus, the "Discovery BNC" board doesn't have 50 Ohm input termination. The JP4 and JP5 jumpers are for AWG output.

Oh, my bad... That's the output!

Post corrected.

[Fungus]

The problem is interfacing the soundcard with the probes (I'm trying to understand how to). I installed the software, but I should do something real with it.

You don't need probes, just use audio jack to crocodile clips cable (or something like that). Set attenuation to 1x.

[2N3055]

So, if I stimulate the circuit with an external WG, the AD2 will bodeplot its response? Thanks.

No, Bode plot and impedance analysis works by controlling generator and scope in synchronization.  AD2 has internal AWG and uses that one...No support for external AWG.

Weird. My copy of the manual says the generator can be external. You might know that if you owned an AD2...



PS: Can your oscilloscope do this?

Thank you for contributing quality content!!
Is this external generator recent addition? I did look into documentation when I was contemplating buying one and don't remember that.. It was long ago though..

One drawback of external generator implemented this way is that you cannot control it in this tracking mode. That means that variable level stimulus is not available which is not strictly necessary but is very helpful with difficult loads.
Also it doesn't know exact frequency but has to measure it, but that is not important because it is good enough. Frequency to mHz is not important here.

Also I don't argue Waveforms can make some pretty graphs. I was asking if measurements are accurate. As I said, there were some reports that phase measurements above 1 Mhz were inaccurate.. So I asked if someone did performance verification... Maybe they advertise only limited frequency on impedance plots because of limited accuracy..

I find responses from Frex and Eggonotto very useful here... You also gave some good info. 

[egonotto]

Hello,

I did the last measurement with the AD2 again with the RTA4000. But the burden is different. C = 41 pF and L = 0.7 uH therefore the load already has an influence.

Best regards
egonotto

[Fungus]

The MSO5074 appears to be €799 at eleshop.eu.

That's without tax so add 20% or so.

[JeremyC]

Hello,

here is a 25 MHz sine with 1Vpp generated by the AD2.


Best regards
egonotto

egonotto, FYI: You can enable sin(x)/x interpolation in the WaveForms and the "ad2_25MHz.png" will look smooth. The sin(x)/x in WaveForms is called "Smooth".

[JeremyC]

I attached images with harmonics content in 10MHz and 25MHz sine waves generated by the integrated AWG.
Since the spectrum analyzer in AD2 is limited by 50MHz, the 25MHz shows only 2nd harmonic.

 

[egonotto]

Hello,

thanks JeremyC.

Again the 25 MHz 1 Vpp from the AD2. The crosstalk is bad but comes from the cables. With the BNC adapter it is better and without cable it is even better but rather useless

Best regards
egonotto

[JeremyC]

Front-end noise. The AD2 is powered from laptop and the flywire cable is disconnected.
 1. 1mV/d, time base 1ms/d
 2. 1mV/d, time base 1us/d
 3. 10mV/d, time base 1ms/d
 4. 10mV/d, time base 1us/d

[JeremyC]

Hello,

thanks JeremyC.

Again the 25 MHz 1 Vpp from the AD2. The crosstalk is bad but comes from the cables. With the BNC adapter it is better and without cable it is even better but rather useless

Best regards
egonotto

Yes, I agree the crosstalk is annoying. Well, it's $399 (I bought my on e-bay for $240, "New, open box") minilab in small, unshielded package. Still, it's very useful for me.

[tautech]

Yep, our most popular budget conscious pairing, SDS1104X-E and SDG1032X and those with a little more go for SDG2042X that if both are 'improved' pushes out to the 120 MHz max of Siglent Bode plot capability.

I just bought a SDS1104X-E + SDG1032X for our local maker space. I got higher end equipment myself but this combo seems excellent for the beginner, for teaching and really for most. We can do almost everything up to RF work at HAM level. Lots of talk about the intuitiveness of instruments in this thread but what about the complete solution? Get those two, connect with the supplied USB cable and DONE. Start focusing on the actual electronics you want to do instead of the instruments.

I don't really get the budget constraints. The MSO5074 appears to be €799 at eleshop.eu. The SDS1104X-E is €429 and SDG1032X is €289 total €718 so why would it be out of budget?

Down the road you will be buying new toys. Do not think what you buy today, no matter the budget, will be the last thing you buy or upgrade :-). But in reality this is a very strong offer that many will never outgrow.

Yup, exactly and a very capable pairing and both hackable too if you must. 

With the 2ch AWG and XY mode in the SDS1104X-E we can also have a play at curve tracing too:
https://www.eevblog.com/forum/testgear/fooln-around-with-dso-awg/

[balnazzar]

The SDS1104X-E is €429 and SDG1032X is €289 total €718 so why would it be out of budget?

To be honest, these are prices without VAT. You have to add 22% to 718 eur.

[balnazzar]

Mh, it's actually a good price. Apart from its 1.5-3V limit and slightly lower sampling rate, what are its limitations with respect, say, a SDG1000X? Thanks.

Datasheet time !

SAG1021I>P13. These have the benefit of an isolated output, ie. not referenced to mains earth.
https://www.siglenteu.com//wp-content/uploads/dlm_uploads/2021/08/SDS1000X-E_DataSheet_EN04D.pdf

This is the datasheet for the scope. Even searching inside it for the WG, there is basically nothing. Is there a datasheet for the SAG1021i? I'm having trouble finding it... Thanks.

[nctnico]

With the 2ch AWG and XY mode in the SDS1104X-E we can also have a play at curve tracing too:
https://www.eevblog.com/forum/testgear/fooln-around-with-dso-awg/

You can do curve tracing like this with any 2 channel function generator and oscilloscope.

[tautech]

Mh, it's actually a good price. Apart from its 1.5-3V limit and slightly lower sampling rate, what are its limitations with respect, say, a SDG1000X? Thanks.

Datasheet time !

SAG1021I>P13. These have the benefit of an isolated output, ie. not referenced to mains earth.
https://www.siglenteu.com//wp-content/uploads/dlm_uploads/2021/08/SDS1000X-E_DataSheet_EN04D.pdf

This is the datasheet for the scope.

It is, and this is where the SAG1021 (now I version) info is plainly listed. Both the earlier and later versions have the same spec of which starts on P13 and continues onto a good chunk of P14.
 

Even searching inside it for the WG, there is basically nothing. Is there a datasheet for the SAG1021i? I'm having trouble finding it... Thanks.

No.

SAG models fit a # of Siglent scopes but as they are not a standalone device but instead optional to the scope which houses the UI for which to control it all specs and usage instructions are included in the scope datasheet and user manual.

Here, I've plucked out the SAG1021I specs from the scope datasheet:
USB AWG Module (four channel SDS1004X-E series option)
Channels 1
Max. Output Frequency 25 MHz
Sampling Rate 125 MSa/s
Frequency Resolution 1 μHz
Frequency Accuracy ±50 ppm
Vertical Resolution 14-bits
Amplitude Range -1.5 ～ +1.5 V (50Ω load) -3 ～ +3 V (High-Z load)
Waveform Type Sine, Square, Ramp, Pulse, Noise, DC and 45 built-in waveforms
Output impedance 50Ω ± 2%
Protection Over-Voltage Protection, Current-Limiting Protection
Insulation Voltage ±42 Vpk (for SAG2021I only)
Sine
Frequency 1 μHz～ 25 MHz
Offset Accuracy(10 kHz) ±(1%*Offset Setting Value +3 mVpp)
Amplitude flatness (10 kHz, 5Vpp) ±0.3 dB
SFDR DC～1 MHz -60dBc
1 MHz～5 MHz -55dBc
5 MHz～25 MHz -50dBc
HD DC～5 MHz -50dBc
5 MHz～25 MHz -45dBc
Square/Pulse
Frequency 1 μHz～ 1 0MHz
Duty Cycle 1% ～99%
Rise/Fall time < 24 ns (10% ～ 90%)
Overshoot(1kHz,1Vpp, Typical) < 3% (typical 1kHz, 1 Vpp)
Pulse Width > 50 ns
Jitter < 500 ps + 10 ppm
Ramp
Frequency 1 μHz～ 300 kHz
Linearity(Typical) < 0.1% of Pk-Pk (Typical, 1 kHz, 1 Vpp, 50% Symmetry)
Symmetry 0% ～ 100%
DC
Offset range ±1.5 V (50Ω load)
±3 V (High-Z load)
Accuracy ±(|offset|*1%+3 mV)
Noise
Bandwidth >25 MHz (-3dB)
Arbitrary Wave
Frequency 1 μHz～ 5 MHz
Wave Length 16 kpts
Sampling Rate 125MSa/s
Lead in EasyWave and U-Disk

Usage info is in the scope user manual on P186:
https://www.siglenteu.com//wp-content/uploads/dlm_uploads/2021/08/SDS1000X-ESDS1000X-U_UserManual_EN05B.pdf


TBH the 4ch X-E scope and SDG1032X is the better pairing if you can afford it and provides for a wider range of needs and as such will serve you better into the future but really what would I know.....I only had these back in 2017 before public release and contributed a little in their development. Just a few months back features were added that we never imagined would be, now to make SDS1104X-E one of the most capable scopes in this price bracket ever produced.