Author Topic: Siglent SDS2000X Plus  (Read 248450 times)

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Offline tautech

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Re: Siglent SDS2000X Plus
« Reply #2675 on: April 20, 2021, 04:37:27 pm »
That last observation just seems to be a Chinese version of "Sod's Law".  :)

https://en.wikipedia.org/wiki/Sod%27s_law
Nah, man from Finland helping man from Austria find error in his setup.  ;)
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Offline rowifi

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Re: Siglent SDS2000X Plus
« Reply #2676 on: April 23, 2021, 09:55:19 am »
SCOPE DC OFFSET

I've had my SDS2104X Plus a few months and hardly used it.. so am not over familiar with its features etc. Just need to look at some low voltages and note that with all channels zeroed and no probes connected, I'm getting up to 10mV ( one division ) offset on the channels all set to x10 probe.
Two are positive by about 8mV and 10mv, the other two are negative by about 8mV and 6mV on the 10mV range.

At 5mv range the worst trace is off by a a quarter of the screens resolution.
Is there a cal function .. is this expected? What's going on?
 

Offline 2N3055

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Re: Siglent SDS2000X Plus
« Reply #2677 on: April 23, 2021, 10:13:00 am »
SCOPE DC OFFSET

I've had my SDS2104X Plus a few months and hardly used it.. so am not over familiar with its features etc. Just need to look at some low voltages and note that with all channels zeroed and no probes connected, I'm getting up to 10mV ( one division ) offset on the channels all set to x10 probe.
Two are positive by about 8mV and 10mv, the other two are negative by about 8mV and 6mV on the 10mV range.

At 5mv range the worst trace is off by a a quarter of the screens resolution.
Is there a cal function .. is this expected? What's going on?

There is a SelfCal function, that you should use any time temperature in room differs mor than few °C from last time you did SelCal. Consult manual.
It is normal, even for 25000 USD scopes (actually especially for those)..
 
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Offline Performa01

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Re: Siglent SDS2000X Plus
« Reply #2678 on: April 25, 2021, 01:20:43 pm »
That last observation just seems to be a Chinese version of "Sod's Law".  :)

https://en.wikipedia.org/wiki/Sod%27s_law
Nah, man from Finland helping man from Austria find error in his setup.  ;)
Mystery solved.

Since I did these measurements outside my lab, I’ve grabbed a bunch of cables that rested in a box for many years, originally from eBay, but never used since. There were a bunch of used cables, which were supposed to be RG316. It was my very first suspicion that they could be 75 ohms (e.g. RG179), but another eBay purchase out of that box, this time not used but in original sealed plastic bags, yet crappy no name cables (clearly labelled as “RG58”), produced very similar results – and this was my only reference at that time.

Meanwhile I have grabbed some known quality cables from my lab and with them the ripple is almost completely gone (<0.2 dB). At the same time, insertion loss is much lower too. See attached screenshots, where you can compare a 100 cm Hyperflex 5 cable (low loss, high shielding) to a crappy NN alleged RG58. The latter is completely unusable and interestingly gives very similar results as the supposed RG316. But this RG58 has crappy connectors too, which make intermittent contact at best.

Of course this also means that the originally used cables were indeed 75 ohms, most likely RG179. I should have known better from the beginning – if you buy used BNC cables anywhere, the probability of getting something from an old video installation is very high…

At least we now know for sure that there is not a problem with either the generator or the DSO.
 
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Offline rf-loop

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Re: Siglent SDS2000X Plus
« Reply #2679 on: April 25, 2021, 02:50:39 pm »
That last observation just seems to be a Chinese version of "Sod's Law".  :)

https://en.wikipedia.org/wiki/Sod%27s_law
Nah, man from Finland helping man from Austria find error in his setup.  ;)
Mystery solved.

Since I did these measurements outside my lab, I’ve grabbed a bunch of cables that rested in a box for many years, originally from eBay, but never used since. There were a bunch of used cables, which were supposed to be RG316. It was my very first suspicion that they could be 75 ohms (e.g. RG179), but another eBay purchase out of that box, this time not used but in original sealed plastic bags, yet crappy no name cables (clearly labelled as “RG58”), produced very similar results – and this was my only reference at that time.

Meanwhile I have grabbed some known quality cables from my lab and with them the ripple is almost completely gone (<0.2 dB). At the same time, insertion loss is much lower too. See attached screenshots, where you can compare a 100 cm Hyperflex 5 cable (low loss, high shielding) to a crappy NN alleged RG58. The latter is completely unusable and interestingly gives very similar results as the supposed RG316. But this RG58 has crappy connectors too, which make intermittent contact at best.

Of course this also means that the originally used cables were indeed 75 ohms, most likely RG179. I should have known better from the beginning – if you buy used BNC cables anywhere, the probability of getting something from an old video installation is very high…

At least we now know for sure that there is not a problem with either the generator or the DSO.

Very excellent, mystery is now solved.

Btw, warning need give also for some new cables and connectors, not only secondhand.
This is really heavy problem after all kind of sellers in many many places, eBay. Ali, Tao, and endless list...


It is really frustrating to find again and again bad measurement results due to crap cables and connectors..  Next time I come here I take one baggage just for Huber+Suhner and some other high quality things...   oh yes in China also some do good connectors but problem looks like that no one sell these in local taobao etc..
example CenRF is one good name and Zdecl very good,   http://en.zdecl.com/   Really nice company btw.
But I have not found good source for small QTY for personal use.

« Last Edit: April 26, 2021, 10:32:03 am by rf-loop »
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Offline Johnny B Good

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Re: Siglent SDS2000X Plus
« Reply #2680 on: April 27, 2021, 02:19:59 am »
@Performa01

 You can sanity check such 'Chinese' cables if you have some means to measure capacitance in picoFarads (or at least in increments of 0.01nanoFarads) and the cable's length.

 Most 50 ohm coax cables exhibit close to a value of 100pF/m whilst 75 ohm cables will typically show a value around the 70pF/m mark (although a 3.3m UHF TV antenna patch lead I tested gave a reading of 170pf - 52pF/m). Surprisingly, if the table linked below can be entirely trusted (it was the first one that included the capacitance per unit length figures - there are probably better sources if you can find them), there can be significant variations from these figures (surely the definition of coaxial cable impedance depends largely on its capacitance per metre value unless an unusual geometry for the centre conductor is being employed?  :-//).

 Irritatingly, the unit of length measurement used in that table for the capacitance is the foot requiring a conversion multiplier factor value of 3.3333 to obtain the capacitance per metre value.

https://www.rfcafe.com/references/electrical/coax-chart.htm

 Whilst checking a few of my own coax patch leads, I discovered a 1m specimen that showed a value of just 81.5pF rather than the more typical 100pF or so I'd been seeing with my other 1m 50 ohm patch leads. Intrigued, I looked for cable markings to identify it but only found a rather cryptic '3D-FB' printed on the jacket. I DDGed it and found this informative page:-

http://www.caledonian-cables.com/products/coaxial-cables/3d-fb.html

 which, to my surprise, quoted a figure of 82 pF/m which left me feeling rather pleased with my 6 or 7 quid investment in this LCR meter I'd built from a Banggood supplied kit. :)
John
 
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Offline Michael YYZ

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Re: Siglent SDS2000X Plus
« Reply #2681 on: April 27, 2021, 03:47:13 am »
My new SDG6000X series AWG came with two one-metre, 3D-FB, BNC-ended coaxial cables. I had no idea about their characteristics since I had never heard about this designation before. Thanks for providing this useful information.

Whilst checking a few of my own coax patch leads, I discovered a 1m specimen that showed a value of just 81.5pF rather than the more typical 100pF or so I'd been seeing with my other 1m 50 ohm patch leads. Intrigued, I looked for cable markings to identify it but only found a rather cryptic '3D-FB' printed on the jacket. I DDGed it and found this informative page:-

http://www.caledonian-cables.com/products/coaxial-cables/3d-fb.html

 which, to my surprise, quoted a figure of 82 pF/m which left me feeling rather pleased with my 6 or 7 quid investment in this LCR meter I'd built from a Banggood supplied kit. :)
 

Offline tautech

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Re: Siglent SDS2000X Plus
« Reply #2682 on: April 27, 2021, 08:45:06 am »
My new SDG6000X series AWG came with two one-metre, 3D-FB, BNC-ended coaxial cables.
Yes the standard 1 GHz BNC cables Siglent provides with some products and also offers as an accessory:
https://siglentna.com/products/accessories/cables/

Notably Siglent NA don't list their 18 GHz cables whereas Siglent INT and Siglent EU do:  :-//
https://int.siglent.com/article/detail-714.html
https://int.siglent.com/article/detail-715.html
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Offline Performa01

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Re: Siglent SDS2000X Plus
« Reply #2683 on: April 27, 2021, 10:31:09 am »
@Performa01

 You can sanity check such 'Chinese' cables if you have some means to measure capacitance in picoFarads (or at least in increments of 0.01nanoFarads) and the cable's length.
Well, that’s a nice idea and in my case it should have worked, because when you think you have RG316 cables (97 pF/m), you should be able to clearly distinguish them from the only possible alternative, the physically similar RG179 (63 pF/m).

Right now I cannot spend much time in my lab (which is in my 2nd residence far away) so I only have the most needed tools here in my regular home – up to now, an LCR meter has not been amongst them.

It might still not be so straight forward if you have some unknown cables – or higher quality cables in general.
On the other hand, most 75 ohms cables are white, so any potential confusion is limited to a few bread & butter types again.

Yes, the bread & butter 50 ohms cables like RG58, RG174, RG213, RG223 are all 101 pF/m, whereas 75 ohms cables are much lower: RG59 (67.6 pF/m), RG179 (63 pF/m).

Yet other, especially high quality (Low Loss) 50 ohms cables usually have lower capacitance as well:


RG316               97 pF/m
MULTIFLEX_86        95 pF/m
H155A01             84 pF/m
3D-FB               84 pF/m
S_04212_B           82 pF/m
CLF200              80 pF/m
HyperFlex 5         74 pF/m

 

Offline Johnny B Good

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Re: Siglent SDS2000X Plus
« Reply #2684 on: April 27, 2021, 12:54:36 pm »
 I was scanning that rfcafe.com list to see if there were any anomalies (remember my suspicions about the 75 ohm cables with higher than the 52pF/m I measured on old style semi-air spaced UHF co-ax and the more typical 55pF/m for its modern day replacement, CT100 PE foam dielectric?) and spotted a value of 12pF/Ft (40pF/m) for the RG223 cable.

 Since this cable is only slightly thicker than RG58 cable, allowing it to be confused with other similar gauge 50 ohm cables and, if the pF/Ft were actually true, a simple capacitance test would lead to its rejection by reason of it measuring as a 93 or 95 ohm cable, I decided to search for datasheets for RG223 cable, landing up on Pasternack's site to download this datasheet from here: -

  https://www.pasternack.com/images/ProductPDF/RG223-U.pdf

 (this was before I spotted the RG223 in your list of 50 ohm coax cables with typical 101pF/m figures).

 I repeated my search and downloaded this pdf from a link on the Farnell web site:-

 http://www.farnell.com/datasheets/2921248.pdf

All of which confirmed my suspicions that not all of those entries in that rfcafe.com list can be trusted. It's a handy list but you need to check out any entries that show unusual values for the pF/Ft figure which is what the 'sanity check' capacitance measurement is relying upon as a means of estimating the most likely Zo value for an 'unknown cable'.

 I suspect this was most likely simply a transcription error made when that list  had first been compiled. It's quite possible there may be some more such errors giving the impression that some of those cable have somehow stepped outside of the laws of physics (as we understand them  ::)).
John
 

Offline Bad_Driver

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Re: Siglent SDS2000X Plus
« Reply #2685 on: April 27, 2021, 02:45:31 pm »
FYI a good overview (made for HAMs) of 50 ohms coax, unfortunately in German but I think it's self explaining.

https://www.funkamateur.de/bauelemente-2.html?file=tl_files/downloads/bauelementeinfo/Koaxialkabel_2.pdf
 
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Offline Performa01

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Re: Siglent SDS2000X Plus
« Reply #2686 on: April 27, 2021, 03:28:06 pm »
I was scanning that rfcafe.com list to see if there were any anomalies (remember my suspicions about the 75 ohm cables with higher than the 52pF/m I measured on old style semi-air spaced UHF co-ax and the more typical 55pF/m for its modern day replacement, CT100 PE foam dielectric?) and spotted a value of 12pF/Ft (40pF/m) for the RG223 cable.

 Since this cable is only slightly thicker than RG58 cable, allowing it to be confused with other similar gauge 50 ohm cables and, if the pF/Ft were actually true, a simple capacitance test would lead to its rejection by reason of it measuring as a 93 or 95 ohm cable, I decided to search for datasheets for RG223 cable, landing up on Pasternack's site to download this datasheet from here: -

  https://www.pasternack.com/images/ProductPDF/RG223-U.pdf

 (this was before I spotted the RG223 in your list of 50 ohm coax cables with typical 101pF/m figures).

 I repeated my search and downloaded this pdf from a link on the Farnell web site:-

 http://www.farnell.com/datasheets/2921248.pdf

All of which confirmed my suspicions that not all of those entries in that rfcafe.com list can be trusted. It's a handy list but you need to check out any entries that show unusual values for the pF/Ft figure which is what the 'sanity check' capacitance measurement is relying upon as a means of estimating the most likely Zo value for an 'unknown cable'.

 I suspect this was most likely simply a transcription error made when that list  had first been compiled. It's quite possible there may be some more such errors giving the impression that some of those cable have somehow stepped outside of the laws of physics (as we understand them  ::)).

Even datasheets can contain (not too few) errors, all the more so webpages that collect a vast amount of data in one big table…

And then there is the sad fact that data sheets are often incomplete. For example, I could not find a specification for the capacitance of the very popular CS29 cable – otherwise I would have included it in my table.

Anyway, even with correct data it’s not straight forward if you have cables from a dubious source. Take my standard lab cable for example, HyperFlex 5 (from a reputable source of course). Despite the huge difference in quality, one might confuse it with RG59 because of the similar diameter, same color – even the minimal bending radius is the same, although the HyperFlex 5 actually feels notably stiffer.

A capacitance measurement has to be fairly accurate to clearly distinguish 67.6 pF/m from 74 pF/m. This should not be a problem as long as you have, say, 10 meters of each cable available. But in practice your piece of cable is less than 2 meters, sometimes even only 25 cm. In this case, stray capacitances might become a major problem - and you have plugs on either end of the cable, which also add some capacitance (that would be roughly the same for any cable), thus additionally swamping the difference in measurement.

In case of BNC cables (and there will hardly be any other connectors used in a lab and for video alike), we can have a look at the pin of the plug. It is thinner for the 75 ohms connector. That was the final evidence for me that the “RG316” was actually some 75 ohms cable.

One mystery remains: my crappy RG58 cables. I bought them as “new” (and they looked like new indeed), sealed in plastic bags, from a professional German eBay seller some ten years ago. If I look at the jacket, I can see “RG58  COAXIAL  CABLE  50OHM” printed on it. The plug has the thicker pin (although totally corroded!), so it has to be 50 ohms indeed. Yet this cable performs at least as bad as the 75 ohms cable did.

Of course I have good quality RG58 too. Just because it was for a different location, I didn’t want to take everything away from my lab but rather thought why not finally put these brand new cables out of this old, untouched purchase to good use at home?

For more serious (and precise) measurements, we don’t want to use standard cables with their high insertion loss anyway. We want low loss and high shielding, which neither RG58 nor RG316 can provide.
In the light of this, it was a rather thoughtless action to include a (supposed) 1.2 mtr RG316 coax connection as reference for the probe measurement. Apart from the ripple, the difference in insertion loss should be obvious.

Here’s the insertion loss at 600 MHz and shielding at a certain frequency for some popular cables:

HyperFlex 5: ~0.20 dB/m, >105 dB @ 100-2000 MHz
RG400:           0.36 dB/m, >81 dB up to 6000 MHz
RG223:           0.43 dB/m, >83 dB up to 1000 MHz
RG58:             0.50 dB/m, >38 dB up to 1000 MHz
RG316:           0.60 dB/m, >38 dB up to 1000 MHz
 
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Offline tautech

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Re: Siglent SDS2000X Plus
« Reply #2687 on: May 11, 2021, 04:15:55 am »
Folks,

I just contributed changes to scopehal to support SDS2000X+. Although scopehal works perfectly well as a scope front end the speed at which you can pull data off the 2000X+ means it's much better suited as a post-processing tool for all sorts of applications....here's it being used for SWD decode on some pretty awfully probed SWDIO/SWCLK signals, for example;

Scopehal, and this driver, should be considered alpha quality and there's work needed, but if anyone fancies helping out with some testing and even coding feel free to head over to https://github.com/azonenberg/scopehal-apps and take a look. There is a supporting discord channel too.

DAVE
I got a PM......

Wants to know how to get GIF's or live video captures from SDS2kX Plus.
We see rf-loop do these things to post here but exactly how is it best done ?
Can the above app do it ?
Advice and wisdom please.
TIA
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Offline thinkfat

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Re: Siglent SDS2000X Plus
« Reply #2688 on: May 11, 2021, 09:23:18 am »
Live video from the scope is through the VNC protocol. I'm sure any VNC client will allow to grab frames and store them as GIF. If the above program supports VNC, should be possible.
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Offline tautech

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Re: Siglent SDS2000X Plus
« Reply #2689 on: May 11, 2021, 10:22:49 am »
Live video from the scope is through the VNC protocol. I'm sure any VNC client will allow to grab frames and store them as GIF. If the above program supports VNC, should be possible.
Thanks.
It would be nice to see someone provide a small example and a dummies guide.
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Offline kcbrown

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Re: Siglent SDS2000X Plus
« Reply #2690 on: May 11, 2021, 06:09:57 pm »
Honestly, why should any of this be a surprise?  You're likely to get better returns from mass manufacturing if you make both probes using the same materials and techniques, and then separate them on the basis of the result of quality checks, than by manufacturing them using different materials and/or techniques.
For such a low cost item post-production testing costs more than the production itself costs. And on top of that the manufacturer doesn't know whether they produce enough of either quality to fullfil demand.

Well, presuming for the moment that they do the testing at all, if they aren't producing enough of the higher-spec model to fulfill demand due to too many failures (and thus too many being binned into the lower-spec category), then that would mean they have a quality control problem on the production side, since the higher-spec version is the manufacturing target.

If they aren't getting enough failures to meet demand for the lower-spec model then they'll just backfill with production of the higher-spec model.

All of this presumes that they do some kind of quality checks of the end product that would allow this kind of differentiation.  Maybe they do and maybe they don't.


Quote
IMHO stories about mass-produced products being binned based on specs are grossly exaggerated (IOW: urban myth).

If that's the case, then obviously the right answer is to mass produce the same higher-spec thing and just ship that.  If you're going to forego the per-unit quality checks anyway then you are certainly going to be cost-sensitive enough to use the same materials, techniques, tooling, etc. for all of the units.  Slap different labels on them to "differentiate" them and you're done.

Also, if you're just doing random sampling of the units, then that won't be enough to make binning possible, and you'd obviously just test the sample for the higher spec because failure of that is what you're going to care about.

In any case, the point is that the near-identical performance between two adjacent models of probes from the same manufacturer shouldn't be a surprise in the slightest.
 

Offline kcbrown

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Re: Siglent SDS2000X Plus
« Reply #2691 on: May 11, 2021, 08:36:45 pm »
And now the 0.5-bit option for ERES is greyed out and cannot be selected. Any idea why?
Because the DSO is in 10 bit mode.
Look at the timebase tab.  ;)

The timebase is the last place I'd expect to see something about the vertical resolution, seeing how the timebase is all about the horizontal characteristics.

I get why they put it there: it's a setting that affects all channels.  And I don't see any good place on the screen to put it, really.  But it's an unintuitive place to put it all the same.
 
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Offline gforster

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Re: Siglent SDS2000X Plus
« Reply #2692 on: June 20, 2021, 04:28:58 pm »
Hello World,

I am new to this forum and very excited about the professional information exchange.

I recently bought a SDS2104X Plus and have to say that it is a real great scope.
During a sine wave measurement I recognized that the amplitude measurement is somewhat strange.
Signal characteristics:
f=1kHz
5V amplitude
0V DC offset

The oscilloscope measures frequency, max_voltage, min_voltage, peak_peak_voltage and rms correctly.
For whatever reason, the measured amplitude is not at all close to 5 volts, but similar to the peak to peak voltage.  :scared:
I just wanted to understand if somebody else also observed this strange behaviour on amplitude measurement.
Attached a screenshot of the oscilloscope reading.
 

Offline tubularnut

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Re: Siglent SDS2000X Plus
« Reply #2693 on: June 20, 2021, 04:43:42 pm »

The oscilloscope measures frequency, max_voltage, min_voltage, peak_peak_voltage and rms correctly.
For whatever reason, the measured amplitude is not at all close to 5 volts, but similar to the peak to peak voltage.  :scared:
I just wanted to understand if somebody else also observed this strange behaviour on amplitude measurement.


This does appear to tie up with Siglent's definition of Amplitude taken from the user manual.

 

Offline Performa01

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Re: Siglent SDS2000X Plus
« Reply #2694 on: June 20, 2021, 04:49:19 pm »
The oscilloscope measures frequency, max_voltage, min_voltage, peak_peak_voltage and rms correctly.
For whatever reason, the measured amplitude is not at all close to 5 volts, but similar to the peak to peak voltage.  :scared:
Yes, even though amplitude measurements are only valid for pulse waveforms, it will measure close to peak-peak when accidentally applied to a sine wave.

A quick look at the user manual or even the description in the measurement window (that appears when the amplitude measurement is selected) should make it clear what an amplitude measurement is.
« Last Edit: June 20, 2021, 04:50:56 pm by Performa01 »
 

Offline gforster

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Re: Siglent SDS2000X Plus
« Reply #2695 on: June 20, 2021, 06:46:20 pm »
The oscilloscope measures frequency, max_voltage, min_voltage, peak_peak_voltage and rms correctly.
For whatever reason, the measured amplitude is not at all close to 5 volts, but similar to the peak to peak voltage.  :scared:
Yes, even though amplitude measurements are only valid for pulse waveforms, it will measure close to peak-peak when accidentally applied to a sine wave.

A quick look at the user manual or even the description in the measurement window (that appears when the amplitude measurement is selected) should make it clear what an amplitude measurement is.

 :-+
thx Performa01 and tubularnut for your quick responses.

You are absolutely right with respect to the description in the user manual and quick help menu.
Nevertheless, the way Siglent interprets amplitude is - at least in my mind - very confusing.
A sine wave signal is described by the formula: y=A*sin(t), where A is the amplitude.
See also wikipedia: https://en.wikipedia.org/wiki/Amplitude

Peak to peak equals 2*A and RMS is A/SQR(2).
Siglent probably calculates RMS from peak-peak, thus V_RMS = V_pk-pk/2/SQR(2).

My take away is, that amplitude measurement is meaningless with SDS2104XPlus oscilloscope on sine wave signals.
The way to derive amplitude is to divide peak-peak by 2.

Again, thanks a lot for your help and clarification.

 

Offline 2N3055

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Re: Siglent SDS2000X Plus
« Reply #2696 on: June 20, 2021, 08:44:22 pm »


To add to already excellent responses.

Hate to be stickler, but link to wikipedia is not exactly in line with your statement. On that graph they define 3 different definitions for amplitude for 3 different measurements: peak amplitude (really wrong name for peak absolute value), P-P amplitude and RMS amplitude..

Scope measurements (not only Siglent, mind you) names are not necessarily mathematically rigorous naming. That is hard to do sometimes. Names given are practical, mnemonic words that hint at measurements function. Incidentally, on Keysight scopes they have same measurement with exactly the same name :"Amplitude".

To be precise, as explained in manual, if you measure pulses, and want to know P-P value of pulse from bottom plateau (part of pulse when pulse settles from undershoot and oscillations to a stable value) to top plateau (defined in same manner as bottom, just for the top), Siglent provided that measurement and it is called "Amplitude", to make a distinction to a P-P amplitude measurement that would include any under/overshot and oscillations, measuring between absolute minimums and maximums.....

So if you want to figure out what are logic levels in some circuit, on SDS2000X+ you use "amplitude" measurement. If you want to see if all under/overshots are within the specs for the logic family or chip in question, you use P-P.

For sinewave, you would not have a need for that type of measurement because it doesn't have that kind of shape to make it sensible.

And also, SDS2000X+ ( and all other scopes with same measurements) have RMS and Stdev measurement. Keysight calls those RMS and AC RMS respectively. And they are not calculated from P-P value by any means, but directly calculated by propper RMS of measurement points in waveform. Make a note that what is called RMS is AC+DC RMS and will differ from AC RMS (stdev)if signal have DC offset...
 
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Offline Fungus

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Re: Siglent SDS2000X Plus
« Reply #2697 on: June 21, 2021, 02:59:30 pm »
This does appear to tie up with Siglent's definition of Amplitude taken from the user manual.

Siglent has their own definition of "amplitude?  :palm:

Yes, even though amplitude measurements are only valid for pulse waveforms, it will measure close to peak-peak when accidentally applied to a sine wave.

That sounds like an "accident" that might happen very often...

« Last Edit: June 21, 2021, 03:01:36 pm by Fungus »
 
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Offline Performa01

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Re: Siglent SDS2000X Plus
« Reply #2698 on: June 22, 2021, 07:42:44 am »
This does appear to tie up with Siglent's definition of Amplitude taken from the user manual.

Siglent has their own definition of "amplitude?  :palm:


Do you really need to demonstrate your ignorance even in threads about Instruments that you’ve never even come close to?

Nearly every serious DSO manufacturer has the Amplitude measurement, following the exact same definition as Siglent does. See the attached excerpts from Kesysight, LeCroy, Rohde & Schwarz and Tektronix. And yes, even Goodwill have it.

For all the Rigol fanboys, I’ve had a look at the MSO5000 and – hurray – even Rigol has it. They just call it differently. We cannot know why Rigol names it “Vamp” when everyone else calls it “Amplitude”, but we do know that intelligent humans should be able to recognize that it’s the same.

Siglent bashing can be a hard job – only promising for knowledgeable people with some experience in T&M.

 

Offline Martin72

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Re: Siglent SDS2000X Plus
« Reply #2699 on: June 22, 2021, 08:26:07 pm »
Siglent has their own definition of "amplitude?  :palm:

A classic own goal... ;)
 
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