Siglent SDS2000X Plus

[emi91]

Hello there,

forum newbie first time posting 
After spending days of reading through all the SDS2000X Plus related threads on this forum, I got myself an SDS2104X+ as an upgrade to my old Rigol DS2072A. The main reasons for this purchase were the 4 channels and the "LeCroy-like" UI of the Siglent scope.
Having played around with the new scope for quite a while, I am pretty impressed of the functionality you get for the money (not to mention the upgrade capabilities...), so the Rigol went straight into the bay.

New stock SDS2104X Plus SN# range SDS2PDDD4R1*** are somewhat quieter than earlier units and it seems a slower fan has now been fitted.
Earlier Plus units were louder than SDS5000X once their smart fan had kicked back after boot but now they're about equal for fan noise.

My unit's SN is in the range tautech mentioned above but it still has the same fan equipped (ADDA AD0912DS-A70GL). Although it is no comparison to the screaming fan in the Rigol scope, I am thinking about replacing the stock fan with a more silent one (e.g. Noctua NF-A9 FLX), because of some annoying low frequency noise.

Has anyone already replaced the stock fan and can share some experience?
What about the unpopulated 4-pin fan connector?

Thanks a lot!

[tautech]

Hello there,

forum newbie first time posting 
After spending days of reading through all the SDS2000X Plus related threads on this forum, I got myself an SDS2104X+ as an upgrade to my old Rigol DS2072A. The main reasons for this purchase were the 4 channels and the "LeCroy-like" UI of the Siglent scope.
Having played around with the new scope for quite a while, I am pretty impressed of the functionality you get for the money (not to mention the upgrade capabilities...), so the Rigol went straight into the bay.

New stock SDS2104X Plus SN# range SDS2PDDD4R1*** are somewhat quieter than earlier units and it seems a slower fan has now been fitted.
Earlier Plus units were louder than SDS5000X once their smart fan had kicked back after boot but now they're about equal for fan noise.

My unit's SN is in the range tautech mentioned above but it still has the same fan equipped (ADDA AD0912DS-A70GL). Although it is no comparison to the screaming fan in the Rigol scope, I am thinking about replacing the stock fan with a more silent one (e.g. Noctua NF-A9 FLX), because of some annoying low frequency noise.

Has anyone already replaced the stock fan and can share some experience?
What about the unpopulated 4-pin fan connector?

Thanks a lot!

Welcome to the forum.

For now I would leave the fan to see if this LF noise you hear changes after some use. Please report back about this.
Enjoy your new Plus. 

[tv84]

Service Manual.

[tautech]

Service Manual.

Yep, it was put online on Siglent websites earlier this month.
Went looking for it yesterday.......
https://int.siglent.com/u_file/document/SDS2000X%20Plus%20Service%20Manual_SM0102XP-E01A.pdf

Edited for clarity.

[tv84]

Sorry, I didn't see you had posted. I decided upon attaching because these things tend to disappear...

[casterle]

enhances the resolution to 10 bits, but the ENOB cannot exceed 9 bits, not even theoretically.

I don't really understand ENOB. I know what the letters stand for, but would appreciate a pointer to something akin to "ENOB for Drooling Idiots: Simplified Version". 

[Martin72]

Hi,

Me too....

We got a HDO6034A at work, a 12bit scope from lecroy - In the specs, the ENOBs are claimed with 8.7bits.
Tomorrow at work, I´ll sign into to get this:

Lecroy White Paper: Comparing High Resolution Oscilloscope Design Approaches

Maybe it got the answer.

[2N3055]

This is really simplistic conceptual view what ENOB means. Really simplistic.
If there is a interest for a actual math, that can be arranged..
But for most this is enough to grasp the concept.

[Martin72]

Oh, two different rectangles...

[2N3055]

Oh, two different rectangles...

LOL...

[Martin72]

OK, serious my friend..

The graphic seems to me, that noisefloor has to be substracted and the rest is the effective number of bits.

A few minutes ago, I´ve compared some lecroy specs.
As I wrote before, the ENOB for the HDO6000 is 8.7 bit, for the Wavepro Scope, much more expensive, it is under 8, appx 7.5 .
Both are "true" 12 bit systems.
What does it means at the end....

[2N3055]

OK, serious my friend..

The graphic seems to me, that noisefloor has to be substracted and the rest is the effective number of bits.

Something like that. There are details how to do it, that complicate it.

A few minutes ago, I´ve compared some lecroy specs.
As I wrote before, the ENOB for the HDO6000 is 8.7 bit, for the Wavepro Scope, much more expensive, it is under 8, appx 7.5 .
Both are "true" 12 bit systems.
What does it means at the end....

It means, that 8 bit scopes are really 6-7 bits (depending on details) and 12 bit scopes are not much more.. But always better than 8 bit ones, because noise can be averaged out..
It also depends on bandwidth. If you enable 20MHz band limit, noise drops and ENOB goes up.
Also with  Lecroy if you use ERES (or some other scope with similar implementation) it will recover some resolution (with less bandwidth of course).
Full ENOB tables are big, for all combination of V/div, bandwith limiters, ERES...

Also ENOB for A/D converters is specified and measured  for single signal of such and such frequency. It will not be same for every frequency.

With scopes, it is usually specified as a difference between the noise floor and bit less than maximum signal level (cca 90% of range of A/D) for that V/div.

Usually fact is ignored that if you feed the scope a signal, there will be distortion artefacts that will add to the noise floor (increase it) difference between signal and noise floor will be less than theoretical.

Really, it is hard to explain it better than Leycroy whitepaper you linked to...
Regards,

[Zlotnik]

enhances the resolution to 10 bits, but the ENOB cannot exceed 9 bits, not even theoretically.

I don't really understand ENOB. I know what the letters stand for, but would appreciate a pointer to something akin to "ENOB for Drooling Idiots: Simplified Version". 

I find the following train of thought intuitive.

Picture SNR: Basically a figure out merit that puts the noise of your measurement system in perspective. Easy!

Now, besides noise, your measurement also gets degraded if part of your signal's power ends up in the wrong spot frequency-wise, as it's distorted by your measurement system. Your signal appears as less far above the noise floor, despite the noise floor not rising at all! Therefore, you have to look at SNR and distortion together. There's different measures for this, like THD+N (total harmonic distortion + noise) or SINAD (signal noise and distortion), which are equivalent as long as you're careful to compare apples with apples (bandwidths for noise & distortion etc)

Next, you imagine a perfect ADC that has the same SINAD as your measurement system, and calculate how many bits that theoretical ADC would need to have: presto! ENOB, effective number of bits.

ENOB is super handy as it squeezes a lot of information on a measurement system's performance into one intuitive number.

However, the above caveat of keeping things comparable (bandwidths, amplitudes, what distortion are we talking about etc) explains why ENOB figures are hard to measure, easy to misunderstand and to incorrectly compare, and very rarely given as actual specs for a complex system like a scope, as opposed to eg an ADC. Without a kilobyte of fine print on how exactly this specific ENOB spec was measured, it can do more harm than good precisely because it looks so nice and intuitive.

Often you're better off just directly comparing a simpler performance metric in one specific comparable situation. Like "Look how much more noise this scope has" or "this one shows steps, the other one is smooth" for the same signal and settings.

I like this analog whitepaper describing things in more detail:
https://www.analog.com/media/en/training-seminars/tutorials/MT-003.pdf

Nice, concise, and with less scope-chauvinism (well deserved as it may be in some cases) as whitepapers from certain well known scope manufacturers ;-)

[casterle]

This is really simplistic conceptual view what ENOB means. Really simplistic.
If there is a interest for a actual math, that can be arranged..
But for most this is enough to grasp the concept.

Thank you! That's exactly what I was looking for.

[tautech]

Seems Tek use a very similar logic probe for their MDO3000 series.
Stolen from another thread:

[Martin72]

Firmware updates came in 3-month order so far, now we got february...Time for a new one.

[tautech]

Firmware updates came in 3-month order so far, now we got february...Time for a new one.

Some units fresh from the factory collected today are still on 1.3.7R5

[ekaszubski]

I'm trying to decide whether to hold out for an SDS2104X-Plus (they're a little hard to get right now apparently) or go for an MSO5074, which are readily available.

Can persistence and color grading be applied to math functions in the SDS2000X-Plus scopes, especially the FFT math function? It seems like these would be particularly useful for basic spectrum analysis but I've struggled to find any pictures or videos of this capability.

In comparison, Rigol has videos showing the MSO5000 drawing an FFT with both persistence and color grading in dot render mode:

I'm looking to upgrade from an Analog Discovery 2.

[Martin72]

Hi,

Just test it out right now on my siglent, colour grading and persistence doesn´t have an effect to math traces like FFT.
Only vector/dot mode.

Martin

[Performa01]

FFT does not support persistence, but it does have max-hold.

[rf-loop]

Hi,

Just test it out right now on my siglent, colour grading and persistence doesn´t have an effect to math traces like FFT.
Only vector/dot mode.

Martin

It is really mystery why persistence is missing. It is  important, in some cases very important, and finally in some cases just mandatory.
Also FFT average mode is not good, least I do not like it. This trace average math need do different way.
You can test. Input 10dBm signal and look this peak in FFT. Set signal level so that it is least >70dB over noise level and trigger auto. Set FFT average 4. Disconnect signal.  Look time when you can not anymore see this signal peak higher than noise level, no need clock just count how many cup of coffee you can drink when waiting. Then set average 30 and test again. but now do not count how many coffee cup... caffeine intoxication is not fun. This average math need correct in some future FW.

Even this older SDS1202X-E have FFT persistence and this is older entry level scope.



455kHz, AM modulation with 100Hz and 120Hz, mod depth 20% (just with 20% mod sidebands levels are -20dBc, as can also see)

Because this, it is hard to believe Siglent do not add this in some next FW update. Why it is not implemented already - I have no idea.

[Electro Fan]

Hi,

Just test it out right now on my siglent, colour grading and persistence doesn´t have an effect to math traces like FFT.
Only vector/dot mode.

Martin

It is really mystery why persistence is missing. It is  important, in some cases very important, and finally in some cases just mandatory.
Also FFT average mode is not good, least I do not like it. This trace average math need do different way.
You can test. Input 10dBm signal and look this peak in FFT. Set signal level so that it is least >70dB over noise level and trigger auto. Set FFT average 4. Disconnect signal.  Look time when you can not anymore see this signal peak higher than noise level, no need clock just count how many cup of coffee you can drink when waiting. Then set average 30 and test again. but now do not count how many coffee cup... caffeine intoxication is not fun. This average math need correct in some future FW.

Even this older SDS1202X-E have FFT persistence and this is older entry level scope.



455kHz, AM modulation with 100Hz and 120Hz, mod depth 20% (just with 20% mod sidebands levels are -20dBc, as can also see)

Because this, it is hard to believe Siglent do not add this in some next FW update. Why it is not implemented already - I have no idea.

"no need clock just count how many cup of coffee you can drink when waiting" 

Edit:  faster FFT would be better and color intensity grading would be really nice.... maybe in a firmware upgrade if tautech votes for it and encourages it with an email or a phone call to Siglent 

[ekaszubski]

Thanks Martin, Performa, rf-loop for the detailed info!

[Analog4]

I'm trying to decide whether to hold out for an SDS2104X-Plus (they're a little hard to get right now apparently) or go for an MSO5074, which are readily available.....

Apparently there is no inventory of SDS2104X-Plus in North America. The story I heard is the Siglent factory is waiting for semiconductor parts from USA to build the inventory, which was depleted, due to popularity. Semiconductor shortage is not just a problem with automobile Mfr being lines down.

Also shipping is an issue, limited container shipping and flights.

Was told the estimated scope availability is end of March 2021.   

[oz2cpu]

any news in getting a good mating connector ?
3D printed cover ?
for the DIY SPL2016 ?
I did find a little bit of random spread information in this huge thread about the logic analyzer DIY,
like pinouts, alot of other posts with this info the pictures or links dont work,
I dont need it that much, so I am not going to pay 400 $ for it,
and when/if i need it, I could be happy with just 4-8 channels.