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Products => Test Equipment => Topic started by: haloway13 on October 16, 2020, 03:45:11 pm

Title: Benefits of going with all Siglent setup
Post by: haloway13 on October 16, 2020, 03:45:11 pm
Hi all,

I would think this has been asked before but I did not find anything that specifically addressed my question.

Is there a benefit to going with one manufacturer?


These three items are currently listed for $389, $499, and $359 respectively for a total of $1247.00 (This is a little more than I want to spend but might be worth it)

Other than the brand look and feel and having similar interfaces (I would hope) are there other advantages of going with the same manufacturer?

same PC Interface?

Thanks in advance!

--Tim
Title: Re: Benefits of going with all Siglent setup
Post by: tv84 on October 16, 2020, 03:51:56 pm
A better bundle price?
Title: Re: Benefits of going with all Siglent setup
Post by: Fungus on October 16, 2020, 04:08:20 pm
Is there a benefit to going with one manufacturer?

Not really.

  • Siglent Technologies SPD3303X-E Triple Output Power Supply
  • Siglent SDS1104X-E 100Mhz digital oscilloscope 4 channels standard decoder
  • Siglent Technologies SDG1032X Arbitrary Waveform - Function Generator

I believe the scope and ARBGEN can talk to each other and do bode plots, but ... together they cost very nearly as much as, eg. a Rigol MSO5000 which can do a lot more (350MHz bandwidth, 8GHz sample rate, more memory, built in function generator, bode plots, big touch screen, etc, etc.)
Title: Re: Benefits of going with all Siglent setup
Post by: mawyatt on October 16, 2020, 04:52:13 pm
Check with Saelig in US, they may have a bundled Siglent discount. They also offer a EEVblog discount.  :-+

Depending on your needs, you might consider the SDS2000X Plus series which comes with a built-in 50MHz AWG. I have the SD2102X Plus (wanted the 2104, but was BO), and have been very impressed. Way more scope than I expected for the $ :-+

The Siglent CS for a 1st time customer has also been top notch ;)

I can't speak about Rigol or others as I haven't evaluated them, but selected the Siglent over the Rigol based upon all the threads. My past experience (>50 yrs) has always been with HP/Agilent/Keysight, Tektronix and a little R&S gear, so a little reluctant to "jump ship" and go with an unknown to me brand, especially an overseas brand  ??? Now I have 3 Siglent instruments, SDS2102X Plus, SDG2042X and SSA3021X Plus, all "upgraded" with the help of folks here on EEVblog :-+

I'm sure whatever you decide, you will enjoy the many fine instruments available from various sources today at modest costs :-+

Best
Title: Re: Benefits of going with all Siglent setup
Post by: rvalente on October 16, 2020, 06:06:26 pm
Hi all,
Is there a benefit to going with one manufacturer?

Maybe a fanboy t-shirt prize? kkkk

Is there a benefit to going with one manufacturer?

Not really.

  • Siglent Technologies SPD3303X-E Triple Output Power Supply
  • Siglent SDS1104X-E 100Mhz digital oscilloscope 4 channels standard decoder
  • Siglent Technologies SDG1032X Arbitrary Waveform - Function Generator

I believe the scope and ARBGEN can talk to each other and do bode plots, but ... together they cost very nearly as much as, eg. a Rigol MSO5000 which can do a lot more (350MHz bandwidth, 8GHz sample rate, more memory, built in function generator, bode plots, big touch screen, etc, etc.)


The rigol MSO5000 would compare to the siglent SDS2000x plus, right?
AFAIK and going off topic,  I've never used this instrument but researched a lot about it. Was once in love with it them totally disappointed, seems to be a very very poor AD resolution (not even 6 full bits) and testimonials says the firmware interface is crap.

I'd say siglent is a more polished instrument, will give less bang for the buck but better usability, altough my experience with siglents and rigols are limited.
Title: Re: Benefits of going with all Siglent setup
Post by: rvalente on October 16, 2020, 06:08:53 pm
I would go for a siglent sds2000x plus scope, would latter get a DG811 gen (and hack it).

As for the power supply if you do not need a very specific function (like programmability) I see no particular reason to get a fancy looking psu with a beautiful display, any old HP 6xxx series is SOOOOOO good, I've many of them.

I would get a 6623 or 6622 any time instead a siglent power supply, these babies are work horses and serviceable.
Title: Re: Benefits of going with all Siglent setup
Post by: mawyatt on October 16, 2020, 06:32:09 pm

The rigol MSO5000 would compare to the siglent SDS2000x plus, right?
AFAIK and going off topic,  I've never used this instrument but researched a lot about it. Was once in love with it them totally disappointed, seems to be a very very poor AD resolution (not even 6 full bits) and testimonials says the firmware interface is crap.

I'd say siglent is a more polished instrument, will give less bang for the buck but better usability, altough my experience with siglents and rigols are limited.

Interesting about the ADC resolution of the MSO05000. I did a quick eval a few days ago of the SDS2102X Plus in 10 bit mode with 20MHz BW, using precision DC and AC references I've developed (based on LM399AH), this was supporting a HP34401A and Agilent34401A calibration. Used a new Keysight 34465A as measurement reference. Here's what I found using DSO statistics measurement function.

KS34465A             SDS2102X Plus
9.99999VDC          9.966VDC
7.04192VDC          7.0092VDC
0.999964VDC        1.0003VDC
100.0005mVDC     98.987mVDC
5.00026VDC          4.9987VDC
2.49994VAC           2.4996VAC (250.000Hz)

Best,
Title: Re: Benefits of going with all Siglent setup
Post by: Fungus on October 16, 2020, 06:45:22 pm
AFAIK and going off topic,  I've never used this instrument but researched a lot about it. Was once in love with it them totally disappointed, seems to be a very very poor AD resolution (not even 6 full bits)

Says who? Where are you getting that idea from?


Title: Re: Benefits of going with all Siglent setup
Post by: Howardlong on October 16, 2020, 08:51:19 pm
AFAIK and going off topic,  I've never used this instrument but researched a lot about it. Was once in love with it them totally disappointed, seems to be a very very poor AD resolution (not even 6 full bits)

Says who? Where are you getting that idea from?

Me probably. Post #1745 https://www.eevblog.com/forum/testgear/siglent-sds2000x-plus-coming/msg3180030/#msg3180030 (https://www.eevblog.com/forum/testgear/siglent-sds2000x-plus-coming/msg3180030/#msg3180030)

I measured it, I'd say it was quite a disappointment considering I'm a bit of a Rigol fan boy. :-(

IMHO Rigol bench AWGs seem better than Siglent's in terms of UI. Occasionally, my Siglent SDG1025 has gone weird on me to the extent of it blowing up a DUT, so I'm naturally wary of it. Typically scopes with integrated AFG/AWG on Rigols offer two channels as opposed to one, and the Rigols offer modulation capabilities. For me the most limiting factor of all scope integrated AFGs is they're very amplitude limited irrespective of brand.

Comparing the SDS1104X-E to the Rigol DS1000Z(plus), if you're not intending to go for the MSO option, the SDS1104X-E is definitely the one to go for, it has a less cluttered UI and feels marginally snappier. However, if you intend to add the MSO option, the SDS1104X-E is almost unusable, both in terms of UI sluggishness and how it takes over your bench top with its stiff cabling. I'd far rather go for the DS1000Z Plus with its respective LA pod.

Note that the SDS1104X-E does integrate with the bench SDG1025 AWG via USB for Bode plots, presumably the SDG1000X series will work too. Alternatively, the Siglent's optional companion single AWG brick, is a bench hog (like the LA), and definitely not a neat solution compared to the Rigol DS1000Z-S models with integrated dual AWG, although note that the Rigol's AWG BNCs are on the rear of the scope. ISTBC but don't think that the DS1000Z-S offers Bode plots, unless it's included in a new version of firmware that I'm not aware of.

I can't really comment on the Siglent power supply, I don't have it. I do have the Rigol DP832, and few other lab bench power supplies. My most used bench supplies are simple small form factor unbranded 0-30V 5A single supply units with 1mA & 10mV resolution, and simple (but separate) voltage and current limit control knobs. The Rigol DP832 is only used about 10% of the time, purely because it's unnecessarily complicated for most of my use cases and needs a bit of boot time. I've never used any of the "advanced functions" such as the Recorder or Analyzer for example in a practical setting. Depending on what you're intending to do, you might find yourself better off with a couple of basic cheap supplies.
Title: Re: Benefits of going with all Siglent setup
Post by: tszaboo on October 16, 2020, 10:18:00 pm
It could be beneficial, if you want to automate a setup, and you dont need to support 2-3 different libraries or APIs or communication protocols. If you dont want to do that, probably you should go for the most suitable equipment, not necessarily from the same brand.
Title: Re: Benefits of going with all Siglent setup
Post by: TK on October 17, 2020, 12:12:39 am
I would go for a siglent sds2000x plus scope, would latter get a DG811 gen (and hack it).

As for the power supply if you do not need a very specific function (like programmability) I see no particular reason to get a fancy looking psu with a beautiful display, any old HP 6xxx series is SOOOOOO good, I've many of them.

I would get a 6623 or 6622 any time instead a siglent power supply, these babies are work horses and serviceable.
SDS2000x plus has AWG integrated, not a good one, but it is there and can do bode plot... no need for the DG811
Title: Re: Benefits of going with all Siglent setup
Post by: tkamiya on October 17, 2020, 12:52:27 am
I don't particularly care about matching manufacturers of my test equipment.  Mine are mostly HP and Tektronics but many of them are generations apart that using them together as a set is not possible.  If I really want to do that, I'd just do GPIB, the defacto standard of all test gear. 

I'd just concentrate on getting the best for the money.  There are so many in used market, for me, it doesn't make sense to go the route you are taking.  I do have a Siglent scope.  It's a fine equipment. 
Title: Re: Benefits of going with all Siglent setup
Post by: Fungus on October 17, 2020, 01:38:49 am
AFAIK and going off topic,  I've never used this instrument but researched a lot about it. Was once in love with it them totally disappointed, seems to be a very very poor AD resolution (not even 6 full bits)

Says who? Where are you getting that idea from?

Me probably. Post #1745 https://www.eevblog.com/forum/testgear/siglent-sds2000x-plus-coming/msg3180030/#msg3180030 (https://www.eevblog.com/forum/testgear/siglent-sds2000x-plus-coming/msg3180030/#msg3180030)

I measured it, I'd say it was quite a disappointment considering I'm a bit of a Rigol fan boy. :-(

Here we see the danger of making statements like that on The Internet without mentioning the test conditions, etc.

People might read that and go around repeating that it has a 6-bit ADC.

Title: Re: Benefits of going with all Siglent setup
Post by: jjoonathan on October 17, 2020, 01:41:35 am
Wait, it's been a few hours since this post and tautech still hasn't weighed in? Do we need to call the police for a wellness check?
Title: Re: Benefits of going with all Siglent setup
Post by: Fungus on October 17, 2020, 01:58:19 am
Interesting about the ADC resolution of the MSO05000. I did a quick eval a few days ago of the SDS2102X Plus in 10 bit mode with 20MHz BW, using precision DC and AC references I've developed (based on LM399AH), this was supporting a HP34401A and Agilent34401A calibration. Used a new Keysight 34465A as measurement reference. Here's what I found using DSO statistics measurement function.

KS34465A             SDS2102X Plus
9.99999VDC          9.966VDC
7.04192VDC          7.0092VDC
0.999964VDC        1.0003VDC
100.0005mVDC     98.987mVDC
5.00026VDC          4.9987VDC
2.49994VAC           2.4996VAC (250.000Hz)


You'll get good results if you put almost anything in "Hi-Res" mode, apply a low pass filter and and take enough averages.

eg. What results do you get if you try that on other 'scopes?

Title: Re: Benefits of going with all Siglent setup
Post by: mawyatt on October 17, 2020, 02:06:12 am
Interesting about the ADC resolution of the MSO05000. I did a quick eval a few days ago of the SDS2102X Plus in 10 bit mode with 20MHz BW, using precision DC and AC references I've developed (based on LM399AH), this was supporting a HP34401A and Agilent34401A calibration. Used a new Keysight 34465A as measurement reference. Here's what I found using DSO statistics measurement function.

KS34465A             SDS2102X Plus
9.99999VDC          9.966VDC
7.04192VDC          7.0092VDC
0.999964VDC        1.0003VDC
100.0005mVDC     98.987mVDC
5.00026VDC          4.9987VDC
2.49994VAC           2.4996VAC (250.000Hz)


You'll get good results if you put almost anything in "Hi-Res" mode, apply a low pass filter and and take enough averages.

eg. What results do you get if you try that on other 'scopes?

Don't have another DSO, although do have 2 Tek 2465s analog scopes.

So why don't you take some measurements with another DSO in "Hi-Res" mode and report what you find ;)

Best,
Title: Re: Benefits of going with all Siglent setup
Post by: Howardlong on October 17, 2020, 02:07:48 am
AFAIK and going off topic,  I've never used this instrument but researched a lot about it. Was once in love with it them totally disappointed, seems to be a very very poor AD resolution (not even 6 full bits)

Says who? Where are you getting that idea from?

Me probably. Post #1745 https://www.eevblog.com/forum/testgear/siglent-sds2000x-plus-coming/msg3180030/#msg3180030 (https://www.eevblog.com/forum/testgear/siglent-sds2000x-plus-coming/msg3180030/#msg3180030)

I measured it, I'd say it was quite a disappointment considering I'm a bit of a Rigol fan boy. :-(

Here we see the danger of making statements like that on The Internet without mentioning the test conditions, etc.

People might read that and go around repeating that it has a 6-bit ADC.

Test conditions are two posts before in post #1743.

(https://www.eevblog.com/forum/testgear/siglent-sds2000x-plus-coming/?action=dlattach;attach=1043426;image)

Effective bits:

(https://www.eevblog.com/forum/testgear/siglent-sds2000x-plus-coming/?action=dlattach;attach=1043460;image)

My comparison of MSO5000 to SDS2000X+

https://www.youtube.com/watch?v=93QUNt1z6Gw (https://www.youtube.com/watch?v=93QUNt1z6Gw)
Title: Re: Benefits of going with all Siglent setup
Post by: Elasia on October 17, 2020, 02:11:50 am
Hi all,

I would think this has been asked before but I did not find anything that specifically addressed my question.

Is there a benefit to going with one manufacturer?

  • Siglent Technologies SPD3303X-E Triple Output Power Supply
  • Siglent SDS1104X-E 100Mhz digital oscilloscope 4 channels standard decoder
  • Siglent Technologies SDG1032X Arbitrary Waveform - Function Generator

These three items are currently listed for $389, $499, and $359 respectively for a total of $1247.00 (This is a little more than I want to spend but might be worth it)

Other than the brand look and feel and having similar interfaces (I would hope) are there other advantages of going with the same manufacturer?

same PC Interface?

Thanks in advance!

--Tim

Hey there.. I run a lot of siglent gear, true benefit of all being the same? Only one i can think of is using a siglent awg with a siglent scope lets you do bode plots.. thats about it honestly

I eval each piece for what it can do and bang per buck.. siglent is typically the best value brand along with say rigol

That said i've had all those pieces.. good kit to start with, this or rigol, cant go wrong really
Title: Re: Benefits of going with all Siglent setup
Post by: rf-loop on October 17, 2020, 03:35:47 am
Interesting about the ADC resolution of the MSO05000. I did a quick eval a few days ago of the SDS2102X Plus in 10 bit mode with 20MHz BW, using precision DC and AC references I've developed (based on LM399AH), this was supporting a HP34401A and Agilent34401A calibration. Used a new Keysight 34465A as measurement reference. Here's what I found using DSO statistics measurement function.

KS34465A             SDS2102X Plus
9.99999VDC          9.966VDC
7.04192VDC          7.0092VDC
0.999964VDC        1.0003VDC
100.0005mVDC     98.987mVDC
5.00026VDC          4.9987VDC
2.49994VAC           2.4996VAC (250.000Hz)


You'll get good results if you put almost anything in "Hi-Res" mode, apply a low pass filter and and take enough averages.

eg. What results do you get if you try that on other 'scopes?

Don't have another DSO, although do have 2 Tek 2465s analog scopes.

So why don't you take some measurements with another DSO in "Hi-Res" mode and report what you find ;)

Best,

And in 10bit mode it also produce 10bit data to acquisition memory. many scopes what do trace average or decimated samplerats box car average do it only for  display but still 8 bit data in memory.  Of course 10bit mode also use more memory, 2 bytes for every 10bit produced data point- naturally.
I do not have this model in my positon far from home at this year but it is nice if someone look this bit more deeply including also data in memory, is it example ready for what ever PC software in .csv mode or do it first need somehow convert, (least I do not have seen this thing here in forum but naturally I have not read every single message here in forum.)

And then, many scopes have some kind of SFRA today. What have this performace what SDS1000X-E, 2000X-E and SDS2000Xplus have.
(Im not sure SDS1000X-C and SDS1000X-U SFRA things at all)
First it need note it have 3 simultaneous channels.
Second it need note it is based to frequency selective sweeping receivers what is big thing in some circumstances when do also other things than just playing fun. And it have also programmable level shape for sweeps what may be very useful when DUT have some active circuits. It is not checkbox feature in shiny brochure. It is real tool (with its limits) but of course it is not like dedicated SFRA instruments or set of instruments in very different price class.
1Hz resolution in 100MHz center and 500Hz span with up to over 120dB measurement dynamics in single sweep. Siglent set performance reference for other manufacturers in this kind of price class - look these Keysight, GoodWill etc jokes....

SDS1104X-E + SAG1021   well, with it can play and do something  but.... 
If I am Siglent I stop immdiately this S-Bus based LA and SG.  I can not understand what they have smoking when they get this idea.... I have not many times seen this kind of <censored>. Oh yes, they can use and they work but... and some peoples are even satisfied. They meet they limited needs.


Imho, basic good set.
SDS1104X-E + SDG1032X (or 1062X) is good set for many kind of work and hobby, lot of basic performance.

Separate machines can use independently and also example for BP (SFRA) it can use also in  generator 2 channel mode what may give big advantage in some SFRA situations.


SDS2104X Plus + SDG2042X (or even 2122X) is better and more expensive set for many works and hobby, lot of more performance and features than first one.
Generator is much better, and scope is lot of better. 
(yes of course 2000XPlus have FG but for serious use mostly need more so this is why I take here least SDG2000X series AWD)



Linear Power Supply. It need note that Siglent have also SPD3303C 

It have overall same performance than, but some tiny feature missing, other ways same as SPD3303X-E
But it do not have this TFT (my own personal taste classify this ugly) where user can not set colors and can not set even brightness, totally like kids designed outlook.
Why my workshop where I need do serious works need look like HongKong street at night with all colors and blinkings and flashings,  like food where all is mixed together as for pig's meal. It may disturb even brain work aka thinking.
C model have, imho, more nice 7 segment LED display what also radiate less EMI.

Title: Re: Benefits of going with all Siglent setup
Post by: tautech on October 17, 2020, 04:36:40 am
Wait, it's been a few hours since this post and tautech still hasn't weighed in? Do we need to call the police for a wellness check?
:-DD
Away for a couple of days ........
Nothing much to add other than all 3 of the OP’s selection can be improved.  ;)
Good choices and all 3 are popular sellers here in NZ.
Title: Re: Benefits of going with all Siglent setup
Post by: Fungus on October 17, 2020, 03:50:21 pm
Test conditions are two posts before in post #1743.

OK, thanks.

Without even going into the chosen setup it's obvious that:
a) Higher bandwidth scope = more noise.
b) More expensive 'scope with lower bandwidth = less noise (the Siglent costs 50% more)

Choose your poison.

OTOH: That setup isn't the way that most people will be using their MSO5000 so it's not fair to say "it has a 6-bit ADC", although that's what the Internet will now parrot forever.   :palm:
Title: Re: Benefits of going with all Siglent setup
Post by: nctnico on October 17, 2020, 04:57:45 pm
Test conditions are two posts before in post #1743.

OK, thanks.

Without even going into the chosen setup it's obvious that:
a) Higher bandwidth scope = more noise.
b) More expensive 'scope with lower bandwidth = less noise (the Siglent costs 50% more)
Not really. The numbers from Howard speak for themselves; the Siglent is clearly the best one from the list. I have owned a Keysight DSO7104A myself and the amount of noise (even with the bandwidth limit on) annoyed me a lot because the details of a signal just get drowned in the noise.
Title: Re: Benefits of going with all Siglent setup
Post by: colorado.rob on October 17, 2020, 07:31:46 pm
Is there a benefit to going with one manufacturer?

No.  I have a bunch of Siglent test gear (DMM, Scope, AWG, SpecAn) and non-Siglent gear (DMMs, PSU, various RF gear).

I bought the Siglent gear because they met my measurement requirements for the least cost.  And that is how I recommend you go about making test gear purchasing decisions.

While the Siglent gear I own have similar face plates and look like they should stack well, they do not because they have different depths.  Siglent could have made the AWG 4-5cm longer so it could stack well with the DMM, but they did not do so.  I think when I was looking at the SDL-1000X DC load, it too had a different depth from both the AWG and DMM.

The items you are looking at are certainly reasonable choices at their price point.  And I have found Siglent to be pretty responsive when it comes to adding features and fixing problems in their firmware.
Title: Re: Benefits of going with all Siglent setup
Post by: Vestom on October 17, 2020, 07:32:13 pm
SDS2000x plus has AWG integrated, not a good one, but it is there and can do bode plot... no need for the DG811
IMHO the AWG is the biggest let-down of the SDS2000X+, which is otherwise a great scope for the price. The hardware seems pretty good with 14bit, 125MS/s and 50MHz BW, but the software implementation is just too basic and only really good for simple fixed (e.g. sine/square) waveforms. No modulation, no pulse train generator, no random noise generator, no noise-on-sine....

The AWG in the SDS2000X+ in its current form is not a replacement for a good signal generator and not up to the implementation in e.g. the R&S RTB2000. However, if Siglent makes a proper signal generator in a future firmware update, this scope is going to be really competitive!

The Bode analyzer functionality is good though (albeit a bit slow).
Title: Re: Benefits of going with all Siglent setup
Post by: Elasia on October 17, 2020, 07:54:54 pm

While the Siglent gear I own have similar face plates and look like they should stack well, they do not because they have different depths.  Siglent could have made the AWG 4-5cm longer so it could stack well with the DMM, but they did not do so. 

This happens to be my biggest gripe about siglent lol... the front stacks easy but then you have to offset the back end... i typically just stack up circuit board samples to the exact height for spacers
Title: Re: Benefits of going with all Siglent setup
Post by: haloway13 on October 18, 2020, 01:00:20 am
So much for me to unpack!!! So many responses! What a wonderful community!

So after reading up on MSO it does not look like I will go that route...

However, a combo Scope and AFG sounds like a good combination. What is the typical use case you have where the combo does not give you good enough amplitude?

What is you suggestion for a Combo Scope/AFG?

Thanks!
--Tim
Title: Re: Benefits of going with all Siglent setup
Post by: 2N3055 on October 18, 2020, 08:30:45 am
SDS2000x plus has AWG integrated, not a good one, but it is there and can do bode plot... no need for the DG811
IMHO the AWG is the biggest let-down of the SDS2000X+, which is otherwise a great scope for the price. The hardware seems pretty good with 14bit, 125MS/s and 50MHz BW, but the software implementation is just too basic and only really good for simple fixed (e.g. sine/square) waveforms. No modulation, no pulse train generator, no random noise generator, no noise-on-sine....

The AWG in the SDS2000X+ in its current form is not a replacement for a good signal generator and not up to the implementation in e.g. the R&S RTB2000. However, if Siglent makes a proper signal generator in a future firmware update, this scope is going to be really competitive!

The Bode analyzer functionality is good though (albeit a bit slow).
Even expensive Keysight 3000T built in AWG generator is very limited (only basic options, and very limited amplitude). It is most useful for FRA, and handy if you just need some small signal quickly, or you want to quickly capture something and than replay.
Most limiting is limited amplitude frankly...

So much for me to unpack!!! So many responses! What a wonderful community!

So after reading up on MSO it does not look like I will go that route...

However, a combo Scope and AFG sounds like a good combination. What is the typical use case you have where the combo does not give you good enough amplitude?

What is you suggestion for a Combo Scope/AFG?

Thanks!
--Tim

Limited amplitude is not limiting only when you use it for signals like audio amp repair and any low level signals.
If you use it only for that, than it's not limiting. But if you do only that, you don't need fully fledged signal generator, a DIY circuit with two opamp and  potentiometer is going to give clean sinewave, variable amplitude signal, for audio amp testing..

If you want to test mosfet switching, for instance, you won't be able to open it fully with 2.5V on the gate....... You pretty much need 10V at 50 Ohm to do that. So for that you need 20V P-P generator.

Idea of signal generator is that it is universal instrument to be used however your imagination would like it, limited by it's specs..

Other limiting factor is that having two synchronised channels is very important. There are many occasions when that is needed.
Title: Re: Benefits of going with all Siglent setup
Post by: tautech on October 18, 2020, 08:35:10 am
So much for me to unpack!!! So many responses! What a wonderful community!

So after reading up on MSO it does not look like I will go that route...

However, a combo Scope and AFG sounds like a good combination. What is the typical use case you have where the combo does not give you good enough amplitude?

What is you suggestion for a Combo Scope/AFG?

Thanks!
--Tim
The greatest versatility is always from a standalone 2ch AWG for feature set, amplitude and current source as many can supply 200mA that can also double as a DC source for small/simple projects.
If it can also be paired with a scope for Bode plot capability you get a useful tool set.

Sure 2 units hog more bench space however the easier usability is such it's better than an all in one scope/AWG.
Title: Re: Benefits of going with all Siglent setup
Post by: Howardlong on October 18, 2020, 09:47:53 am
Test conditions are two posts before in post #1743.

OK, thanks.

Without even going into the chosen setup it's obvious that:
a) Higher bandwidth scope = more noise.


You’ll see I had the 20MHz bandwidth limit apploed in all cases.
Title: Re: Benefits of going with all Siglent setup
Post by: Howardlong on October 18, 2020, 10:11:14 am

However, a combo Scope and AFG sounds like a good combination. What is the typical use case you have where the combo does not give you good enough amplitude?

What is you suggestion for a Combo Scope/AFG?
--Tim

Mostly for me it’s microcontroller ADCs with Vref over 2.5V, so, for example, a 2.5V AWG maximum often won’t test through the ADC’s full range.

The Rigols seems to be the best in terms of having 2 channels, and modulation and even AWG capabilities, but are limited to +/-2.5V. I’m not aware of any other scope AFG offering modulation capabilities, and very few offer dual channel.

Siglents top out at +/-3V and is single channel, and offers no AWG capability or modulation.

Keysights top out at +/-5V and are single channel on the 3000 series, dual channel on the 4000 and 6000, and do offer AWG capability but no modulation.

Tek MDOs are +/-5V and offer no AWG or modulati9n capability.




Title: Re: Benefits of going with all Siglent setup
Post by: nctnico on October 18, 2020, 10:24:01 am

However, a combo Scope and AFG sounds like a good combination. What is the typical use case you have where the combo does not give you good enough amplitude?

What is you suggestion for a Combo Scope/AFG?
--Tim

Mostly for me it’s microcontroller ADCs with Vref over 2.5V, so, for example, a 2.5V AWG maximum often won’t test through the ADC’s full range.

The Rigols seems to be the best in terms of having 2 channels, and modulation and even AWG capabilities, but are limited to +/-2.5V. I’m not aware of any other scope AFG offering modulation capabilities, and very few offer dual channel.

Siglents top out at +/-3V and is single channel, and offers no AWG capability or modulation.

Keysights top out at +/-5V and are single channel on the 3000 series, dual channel on the 4000 and 6000, and do offer AWG capability but no modulation.

Tek MDOs are +/-5V and offer no AWG or modulati9n capability.
For completeness: the R&S RTM3000 offers modulation, arbitrary (32kpts) and noise. All in all it is a pretty complete generator. I do use it every now and then. Unfortunately there is no way to trigger on the internal generator though.
Title: Re: Benefits of going with all Siglent setup
Post by: 2N3055 on October 18, 2020, 10:49:07 am

However, a combo Scope and AFG sounds like a good combination. What is the typical use case you have where the combo does not give you good enough amplitude?

What is you suggestion for a Combo Scope/AFG?
--Tim

Mostly for me it’s microcontroller ADCs with Vref over 2.5V, so, for example, a 2.5V AWG maximum often won’t test through the ADC’s full range.

The Rigols seems to be the best in terms of having 2 channels, and modulation and even AWG capabilities, but are limited to +/-2.5V. I’m not aware of any other scope AFG offering modulation capabilities, and very few offer dual channel.

Siglents top out at +/-3V and is single channel, and offers no AWG capability or modulation.

Keysights top out at +/-5V and are single channel on the 3000 series, dual channel on the 4000 and 6000, and do offer AWG capability but no modulation.

Tek MDOs are +/-5V and offer no AWG or modulati9n capability.
For completeness: the R&S RTM3000 offers modulation, arbitrary (32kpts) and noise. All in all it is a pretty complete generator. I do use it every now and then. Unfortunately there is no way to trigger on the internal generator though.

Keysight 3000T also have modulation (AM,FM and FSK) but only on sinewave. Output is only 2.5V in 50 Ohm (5 V P-P only High-Z). IT has no sweeps. You do have logic level presets, add noise to signal and very easy and nicely made copy from channel capture and fairly useful editing of AWG.
All in all, useful in a pinch, but very limited.

I use it mostly for FRA and to capture some signal (from sensor for instance) and replay it, with ability to set amplitude and add noise... I use that on Picoscope too.. For low frequency signals and finer resolution I use 16 bit Pico.

That's for quick test, easy to simply capture real sensor and replay. If I need something more elaborate/defined, than I create AWG waveform for "real" AWG and load it to either Siglent or Rigol I have..
Title: Re: Benefits of going with all Siglent setup
Post by: haloway13 on October 18, 2020, 05:58:23 pm
Somehow after reading every post's suggestion I have arrived at the same list of Siglent pieces.

Siglent Technologies SPD3303X-E Triple Output Power Supply
Siglent SDS1104X-E 100Mhz digital oscilloscope 4 channels standard decoder
Siglent Technologies SDG1032X Arbitrary Waveform - Function Generator

What are the same comparable items with Rigol? My head is swimming with too many model numbers and features!

Thanks!
Tim
Title: Re: Benefits of going with all Siglent setup
Post by: haloway13 on October 18, 2020, 06:08:48 pm
I think these are the alternatives in Rigol:

Rigol DG1032Z 30MHz Arbitrary Waveform Function Generator   
Rigol DP832 195W Power Supply   
Rigol DS1054Z 50MHz 4-Ch Digital Oscilloscope
Title: Re: Benefits of going with all Siglent setup
Post by: Fungus on October 18, 2020, 08:02:39 pm
You’ll see I had the 20MHz bandwidth limit apploed in all cases.

Yes, I saw that, but the statement still applies.

The dangerous part is extrapolating your result to when 20MHz limiter isn't enabled*. You're assuming the Rigol noise will increase in exactly the same way as the Siglent noise.

(*) ie. the Way the 'scope is generally used.
Title: Re: Benefits of going with all Siglent setup
Post by: Howardlong on October 18, 2020, 09:35:03 pm
You’ll see I had the 20MHz bandwidth limit apploed in all cases.

Yes, I saw that, but the statement still applies.

The dangerous part is extrapolating your result to when 20MHz limiter isn't enabled*. You're assuming the Rigol noise will increase in exactly the same way as the Siglent noise.

(*) ie. the Way the 'scope is generally used.

But if I hadn't used the BW limiter, everyone would have complained that I wasn't comparing like for like. It wasn't to try to manipulate the results, quite the opposite in fact.

Either way, it's a pretty bad result for the Rigol. The first thing I noticed when using thus scope was the noise, and that was without the BW limiter: as you say that's how it's typically used. I didn't put the BW limit on to make the Rigol look bad, I just wanted a level playing field.

It's just not the result either of us wanted.

Title: Re: Benefits of going with all Siglent setup
Post by: nctnico on October 18, 2020, 10:26:11 pm
You’ll see I had the 20MHz bandwidth limit apploed in all cases.

Yes, I saw that, but the statement still applies.

The dangerous part is extrapolating your result to when 20MHz limiter isn't enabled*. You're assuming the Rigol noise will increase in exactly the same way as the Siglent noise.

(*) ie. the Way the 'scope is generally used.
Actually I usually have the bandwidth limiter enabled on my oscilloscopes at appropriate bandwidths. It gives the cleanest signal for a given measurement.
Title: Re: Benefits of going with all Siglent setup
Post by: Fungus on October 18, 2020, 11:28:25 pm
But if I hadn't used the BW limiter, everyone would have complained that I wasn't comparing like for like.

That's the problem: You aren't.

A person could easily need the Siglent for one type of job and the Rigol for another type of job. Neither is "best".

I didn't put the BW limit on to make the Rigol look bad, I just wanted a level playing field.

I'm not accusing you of trying to make it look bad (or of anything else in particular). The problem is that the Internet will now parrot "Rigol only has six bits" for all time.

Maybe some of the Rigol noise appears a bit further down the circuit path, after the 20Mhz limiting capacitor.

What noise levels do you see with the limiter off? That the figure would be interesting, too. Also: How much effect does the 20Mhz limiter have on each 'scope? Some of them might have a better limiter (ie. more than capacitor).
Title: Re: Benefits of going with all Siglent setup
Post by: nctnico on October 18, 2020, 11:55:10 pm
Maybe some of the Rigol noise appears a bit further down the circuit path, after the 20Mhz limiting capacitor.

What noise levels do you see with the limiter off? That the figure would be interesting, too. Also: How much effect does the 20Mhz limiter have on each 'scope? Some of them might have a better limiter (ie. more than capacitor).
Don't be so hung up on why the Rigol performs worse. If the noise is bad with the 20MHz limiter it will be worse without the 20MHz limiter. Usually the 20MHz bandwidth limiter is a 1st order filter so don't expect big differences between various oscilloscopes. You'll have to live with the Rigol MSO 5k series having 6 bits only. I agree that this is dissapointing; usually the ENOB drops at much higher frequencies (hundreds of MHz). Having an ENOB of only 6 bits with the 20MHz bandwidth limiter on is pretty bad. Especially for today's standard. It seems that Rigol's own chipset has been a bridge too far and it is not the leap ahead they promise it to be.
Title: Re: Benefits of going with all Siglent setup
Post by: rvalente on October 19, 2020, 09:19:38 pm
It seems that Rigol's own chipset has been a bridge too far and it is not the leap ahead they promise it to be.

Well, that's life, you get what you pay for. The MSO5000 is for me remarkable scope but i'd still prefer to own the SDS2000x+ because it seems more polished to me and frankly, I see no reason to have a 8gsa/s converter for a 350MHz signal, thats almost 23x (also, whats the point of having such high frequency and no 50ohm input, nahhh).
Title: Re: Benefits of going with all Siglent setup
Post by: colorado.rob on October 21, 2020, 02:28:18 am
I think these are the alternatives in Rigol:

Rigol DG1032Z 30MHz Arbitrary Waveform Function Generator   
Rigol DP832 195W Power Supply   
Rigol DS1054Z 50MHz 4-Ch Digital Oscilloscope

For the power supply, if I were buying one today, I would probably go with a GW Instek GPP model with the LAN option.

This is the 4-channel one.  You can find the 3-channel model a bit cheaper.
https://www.tequipment.net/Instek/GPP-4323/DC-Power-Supplies-/-Lab-Power-Supplies/ (https://www.tequipment.net/Instek/GPP-4323/DC-Power-Supplies-/-Lab-Power-Supplies/)

There's a good discussion about it here: https://www.eevblog.com/forum/testgear/seeking-psu-advice-rohde-schwarz-nge103b-com3-or-keysight-e36313a/msg3230970/#msg3230970 (https://www.eevblog.com/forum/testgear/seeking-psu-advice-rohde-schwarz-nge103b-com3-or-keysight-e36313a/msg3230970/#msg3230970)
Title: Re: Benefits of going with all Siglent setup
Post by: ahope on October 21, 2020, 06:37:04 am
I think these are the alternatives in Rigol:

Rigol DG1032Z 30MHz Arbitrary Waveform Function Generator   
Rigol DP832 195W Power Supply   
Rigol DS1054Z 50MHz 4-Ch Digital Oscilloscope

For the power supply, if I were buying one today, I would probably go with a GW Instek GPP model with the LAN option.

This is the 4-channel one.  You can find the 3-channel model a bit cheaper.
https://www.tequipment.net/Instek/GPP-4323/DC-Power-Supplies-/-Lab-Power-Supplies/ (https://www.tequipment.net/Instek/GPP-4323/DC-Power-Supplies-/-Lab-Power-Supplies/)

There's a good discussion about it here: https://www.eevblog.com/forum/testgear/seeking-psu-advice-rohde-schwarz-nge103b-com3-or-keysight-e36313a/msg3230970/#msg3230970 (https://www.eevblog.com/forum/testgear/seeking-psu-advice-rohde-schwarz-nge103b-com3-or-keysight-e36313a/msg3230970/#msg3230970)

Agree completely.
I am a big Siglent fanboy, but for the power supply I went with the GW Instek GPP-4323.
Four channels supply, two channels load, fantastic display (even better than 3055).
Remote software sucks though, Siglent scores higher in that regard.
Title: Re: Benefits of going with all Siglent setup
Post by: Teti on October 21, 2020, 07:13:52 pm
Siglent fanboy here!  :-DD
I went for SDS1104XE scope, and SDG2082X sig gen as they outperform Rigol in the same class, allround much better product.
However I will go for Rigol DP832 bench PS as Siglent is not really 3 channel, more like 2 real channels with slapped on wall wart inside as extra. Will go for Siglent 5 1/2 DMM as much better display.
Benefit of having all siglent is that you can transfer stuff between devices etc. I don't use it at the moment, but I'm pretty sure this will be handy in the future!
Title: Re: Benefits of going with all Siglent setup
Post by: Howardlong on October 22, 2020, 12:23:38 pm
It seems that Rigol's own chipset has been a bridge too far and it is not the leap ahead they promise it to be.

Well, that's life, you get what you pay for. The MSO5000 is for me remarkable scope but i'd still prefer to own the SDS2000x+ because it seems more polished to me and frankly, I see no reason to have a 8gsa/s converter for a 350MHz signal, thats almost 23x (also, whats the point of having such high frequency and no 50ohm input, nahhh).

That's pretty much my take, and I have both. As a bit of a Rigol fanboi myself, and having had a mediocre experience with the only bit of Siglent gear I had in the lab, I wasn't expecting much from the SDS2000X+, but it far out performed my expectations in terms of UI, functionality, performance and polish. On the other hand, while I had high hopes for it, I found the Rigol somewhat disappointing in many respects, the most egregious being the aforementioned noise and the UI sluggishness particularly when changing timebase.

Almost all of the Rigol deficiencies could be resolved with software updates, although I suspect the noise thing is endemic. I was glad to see that the dim screen reported by some on the Rigol was not present on mine. Bearing in mind the Rigol has been out for far longer than the Siglent, I'd have expected the Rigol to be more polished, but the exact opposite was true IME.

The three main negative takeaways for me on the Siglent were (a) the lack of decoder search functionality, (b) many functions are only available on the touch screen and (c) the memory management. None of these are a deal breaker IMHO. The Rigol will do decoder search, but only on the analogue channels for some bizarre reason. I don't have it on the bench right now, but almost all of the Rigol functionality can be accessed by the physical buttons & knobs, and the memory management seemed pretty reasonable to me.
Title: Re: Benefits of going with all Siglent setup
Post by: eeviking on October 22, 2020, 04:53:25 pm
Somehow after reading every post's suggestion I have arrived at the same list of Siglent pieces.

Siglent Technologies SPD3303X-E Triple Output Power Supply
Siglent SDS1104X-E 100Mhz digital oscilloscope 4 channels standard decoder
Siglent Technologies SDG1032X Arbitrary Waveform - Function Generator

What are the same comparable items with Rigol? My head is swimming with too many model numbers and features!

Thanks!
Tim
Just to add some more water to the pool  ;)

I would save some on the PSU and go for a SPD3303C
It's the same psu as the SPS3303X-E just without the fancy lcd and ethernet.
Over here it's 150€ cheaper and in my opinion better bang for the buck.

Then spend some more on the scope and upgrade to a SDS2102X Plus or SDS2104X Plus and use the built in generator for now.
I believe there is a DIY solution to cheaper MSO pods that maybe could "make up" for the missing channels on the SDS2102X Plus

If you really need a dedicated AWG I would go all in for a SDG2042X

Disclaimer:
I have SPD3303C, SDS1104X, SDG805 and kind of regret cheaping out on the scope and AWG but not the PSU.

Title: Re: Benefits of going with all Siglent setup
Post by: TurboTom on October 26, 2020, 06:11:33 pm


...

Test conditions are two posts before in post #1743.

(https://www.eevblog.com/forum/testgear/siglent-sds2000x-plus-coming/?action=dlattach;attach=1043426;image)

Effective bits:

(https://www.eevblog.com/forum/testgear/siglent-sds2000x-plus-coming/?action=dlattach;attach=1043460;image)

My comparison of MSO5000 to SDS2000X+

https://www.youtube.com/watch?v=93QUNt1z6Gw (https://www.youtube.com/watch?v=93QUNt1z6Gw)

I'm sorry but I dare to question @Howardlong's findings on the MSO5000 rms noise and thus the calculated equivalent resolution.

Just compare the peak-to-peak with rms noise figures at 500mV/div setting:

Vpp - 44.5mV
Vrms - 44.2mV

These two numbers are more or less identical which is mathematically impossible in case of an observation of AC signals. Vrms cannot be higher than Vp = 1/2 Vpp, which is the case if the signal has true square shape. And noise doesn't look that much like a square wave... On average, the crest factor for white noise can be assumed to be in the ballpark of 4, thus Vrms should be closse to 1/8 Vpp which matches the figures of the "big" Keysight and the TEK surprisingly well.

To explain the measured figures, I state that all those numbers that deviated considerably from the 1/8 relation had some amount of DC offset superimposed. This is easily overlooked since the zero marker is such a tiny pip at the left border of the screen... The better method of evaluating the AC component of Vrms using internal measurements is just taking the standard deviation of Vpp. This eliminates the average (DC offset) by summing up geometrically the difference of the individual measurements minus the average, e voila -- AC RMS  ;).

The resulting equivalent resolution figures for some of the scopes will turn out much better if this calculation is done properly, but this wouldn't change the impression the reader now already memorized that the MSO5000 has got a front-end that's noisy like the Niagara falls... The apparent noise definitely differs, and Rigol for sure is among the noisier "party", but it's definitely not as bad as Howard evaluated in his table. Much of the apparent noise is also contributed to the way the traces are visualized, and Rigol's display engine traditionally emphasizes the extremal values and thus makes their scopes appear more noisy.

I'm not a Rigol or Siglent fanboy - I own gear of both companies and also had some "buyer's remorse" with both, but I think when publishing a comparison like this, we should at least make sure that the figures make sense from a mathematical point of view...
Title: Re: Benefits of going with all Siglent setup
Post by: nctnico on October 26, 2020, 07:15:11 pm
Well spotted! It is however possible the Vrms calculation in the MSO5000 is wrong  >:D
Title: Re: Benefits of going with all Siglent setup
Post by: 2N3055 on October 26, 2020, 07:57:16 pm
So if I'm not wrong my calc for MSOX3104T would go like this, for those conditions:

[attachimg=1]

and

[attachimg=2]

so that gives:

[attachimg=3]


Although ENOB is not single number, it is frequency/ENOB graph....
Title: Re: Benefits of going with all Siglent setup
Post by: Howardlong on October 26, 2020, 08:17:19 pm


...

Test conditions are two posts before in post #1743.

(https://www.eevblog.com/forum/testgear/siglent-sds2000x-plus-coming/?action=dlattach;attach=1043426;image)

Effective bits:

(https://www.eevblog.com/forum/testgear/siglent-sds2000x-plus-coming/?action=dlattach;attach=1043460;image)

My comparison of MSO5000 to SDS2000X+

https://www.youtube.com/watch?v=93QUNt1z6Gw (https://www.youtube.com/watch?v=93QUNt1z6Gw)

I'm sorry but I dare to question @Howardlong's findings on the MSO5000 rms noise and thus the calculated equivalent resolution.

Just compare the peak-to-peak with rms noise figures at 500mV/div setting:

Vpp - 44.5mV
Vrms - 44.2mV

These two numbers are more or less identical which is mathematically impossible in case of an observation of AC signals. Vrms cannot be higher than Vp = 1/2 Vpp, which is the case if the signal has true square shape. And noise doesn't look that much like a square wave... On average, the crest factor for white noise can be assumed to be in the ballpark of 4, thus Vrms should be closse to 1/8 Vpp which matches the figures of the "big" Keysight and the TEK surprisingly well.

To explain the measured figures, I state that all those numbers that deviated considerably from the 1/8 relation had some amount of DC offset superimposed. This is easily overlooked since the zero marker is such a tiny pip at the left border of the screen... The better method of evaluating the AC component of Vrms using internal measurements is just taking the standard deviation of Vpp. This eliminates the average (DC offset) by summing up geometrically the difference of the individual measurements minus the average, e voila -- AC RMS  ;).

The resulting equivalent resolution figures for some of the scopes will turn out much better if this calculation is done properly, but this wouldn't change the impression the reader now already memorized that the MSO5000 has got a front-end that's noisy like the Niagara falls... The apparent noise definitely differs, and Rigol for sure is among the noisier "party", but it's definitely not as bad as Howard evaluated in his table. Much of the apparent noise is also contributed to the way the traces are visualized, and Rigol's display engine traditionally emphasizes the extremal values and thus makes their scopes appear more noisy.

I'm not a Rigol or Siglent fanboy - I own gear of both companies and also had some "buyer's remorse" with both, but I think when publishing a comparison like this, we should at least make sure that the figures make sense from a mathematical point of view...

You're right to question them, as did I at the time.

The figures are from the scope's own measurements.

Title: Re: Benefits of going with all Siglent setup
Post by: TurboTom on October 26, 2020, 11:21:39 pm
Howard -
on Rigol gear (I cannot tell for other brands), the RMS measurement always outputs AC+DC. And since the scope cannot distinguish between DC offset and DC signal component, and Rigol's frontends are notorious for considerable offset drift during warm-up, this effect can and will affect RMS readings considerably. Especially depending on where in the signal chain the offset drift happens, this may not be limited to the high sensitivity vertical ranges.

In order to retrieve a proper AC RMS reading to compare frontend noise, it's advisable to enable statistics on the Vpp measurement; the standard deviation will then contain the relevant figure.

Do you still have access to all the scopes that you listed in your table? It would be great if we could repeat the test with the DC offset component eliminated. If not, maybe other owners could possibly jump in. In this case, the input configuraion would have to be specified though (50R terminator, shorted, open but capped or just open).

Cheers,
Thomas
Title: Re: Benefits of going with all Siglent setup
Post by: mawyatt on October 27, 2020, 02:27:34 am
So if I'm not wrong my calc for MSOX3104T would go like this, for those conditions:

(Attachment Link)

and

(Attachment Link)

so that gives:

(Attachment Link)


Although ENOB is not single number, it is frequency/ENOB graph....

Shouldn't the ENOB be computed based upon a sine wave input of full scale peak to peak (8 divisions)? If so then the relative signal power would be (4*scalefacor/rt2)^2, or 8*(Scale Factor)^2.

Best,
Title: Re: Benefits of going with all Siglent setup
Post by: 2N3055 on October 27, 2020, 08:32:43 am
So if I'm not wrong my calc for MSOX3104T would go like this, for those conditions:

(Attachment Link)

and

(Attachment Link)

so that gives:

(Attachment Link)


Although ENOB is not single number, it is frequency/ENOB graph....

Shouldn't the ENOB be computed based upon a sine wave input of full scale peak to peak (8 divisions)? If so then the relative signal power would be (4*scalefacor/rt2)^2, or 8*(Scale Factor)^2.

Best,

To be honest ENOB is supposed to be measured specified with the actual signal at actual frequency, so it includes both noise and distortions in SINAD.

In this case we assume (for 2mv/div for instance) full scale P-P sine signal of 16 mV.  RMS of that (11,35mV) divided with RMS of noise (110 uV) gives 10641 ratio, convert that to dB (power ratio) gives 40,2dB,  and converted to ENOB :6,397 bit.

I did quick test with R&S method and got same results.

These tests will have major source of error in scopes built in RMS function and it's limits to deal with calculating RMS of noise and otherwise very complex signal.
 
Please correct me if I'm wrong..

Regards,
Title: Re: Benefits of going with all Siglent setup
Post by: Howardlong on October 27, 2020, 08:59:37 am
Please note that my table was effective resolution, not ENOB; there is a difference.

TurboTom: I do still have the scopes, but I'm very time poor at the moment.
Title: Re: Benefits of going with all Siglent setup
Post by: mawyatt on October 27, 2020, 01:06:05 pm
So if I'm not wrong my calc for MSOX3104T would go like this, for those conditions:

(Attachment Link)

and

(Attachment Link)

so that gives:

(Attachment Link)


Although ENOB is not single number, it is frequency/ENOB graph....

Shouldn't the ENOB be computed based upon a sine wave input of full scale peak to peak (8 divisions)? If so then the relative signal power would be (4*scalefacor/rt2)^2, or 8*(Scale Factor)^2.

Best,

To be honest ENOB is supposed to be measured specified with the actual signal at actual frequency, so it includes both noise and distortions in SINAD.

In this case we assume (for 2mv/div for instance) full scale P-P sine signal of 16 mV.  RMS of that (11,35mV) divided with RMS of noise (110 uV) gives 10641 ratio, convert that to dB (power ratio) gives 40,2dB,  and converted to ENOB :6,397 bit.

I did quick test with R&S method and got same results.

These tests will have major source of error in scopes built in RMS function and it's limits to deal with calculating RMS of noise and otherwise very complex signal.
 
Please correct me if I'm wrong..

Regards,

I had seen the IEEE definition on ENOB, and agree it's without signal distortion and not at a specified signal frequency since no signal is actually applied. So maybe a best case ENOB, or as Howard mentioned Effective Resolution.

From above "In this case we assume (for 2mv/div for instance) full scale P-P sine signal of 16 mV.  RMS of that (11,35mV) divided with RMS of noise (110 uV) gives 10641 ratio, convert that to dB (power ratio) gives 40,2dB,  and converted to ENOB :6,397 bit."
Since the peak to peak full scale signal would yield a sine wave of 4 divisions peak, the RMS would not be of the 8 division peak to peak value, but of the 4 division value. So this would yield 4*2mV/rt2 = 5.657mV RMS, not 8*2mV/rt2 = 11.35mV??

Just trying to follow the thinking behind these calculations, so I can supply a similar set of values that are consistent with what's been shown.

Best,
Title: Re: Benefits of going with all Siglent setup
Post by: mawyatt on October 27, 2020, 01:22:20 pm
Please note that my table was effective resolution, not ENOB; there is a difference.

TurboTom: I do still have the scopes, but I'm very time poor at the moment.

Could you show how you calculated the Effective Resolution in your table so we can compare results on an "Apples to Apples" basis.

BTW thanks for showing the table and taking the time to post these results :-+

Best,
Title: Re: Benefits of going with all Siglent setup
Post by: 2N3055 on October 27, 2020, 02:03:10 pm
So if I'm not wrong my calc for MSOX3104T would go like this, for those conditions:

(Attachment Link)

and

(Attachment Link)

so that gives:

(Attachment Link)


Although ENOB is not single number, it is frequency/ENOB graph....

Shouldn't the ENOB be computed based upon a sine wave input of full scale peak to peak (8 divisions)? If so then the relative signal power would be (4*scalefacor/rt2)^2, or 8*(Scale Factor)^2.

Best,

To be honest ENOB is supposed to be measured specified with the actual signal at actual frequency, so it includes both noise and distortions in SINAD.

In this case we assume (for 2mv/div for instance) full scale P-P sine signal of 16 mV.  RMS of that (11,35mV) divided with RMS of noise (110 uV) gives 10641 ratio, convert that to dB (power ratio) gives 40,2dB,  and converted to ENOB :6,397 bit.

I did quick test with R&S method and got same results.

These tests will have major source of error in scopes built in RMS function and it's limits to deal with calculating RMS of noise and otherwise very complex signal.
 
Please correct me if I'm wrong..

Regards,

I had seen the IEEE definition on ENOB, and agree it's without signal distortion and not at a specified signal frequency since no signal is actually applied. So maybe a best case ENOB, or as Howard mentioned Effective Resolution.

From above "In this case we assume (for 2mv/div for instance) full scale P-P sine signal of 16 mV.  RMS of that (11,35mV) divided with RMS of noise (110 uV) gives 10641 ratio, convert that to dB (power ratio) gives 40,2dB,  and converted to ENOB :6,397 bit."
Since the peak to peak full scale signal would yield a sine wave of 4 divisions peak, the RMS would not be of the 8 division peak to peak value, but of the 4 division value. So this would yield 4*2mV/rt2 = 5.657mV RMS, not 8*2mV/rt2 = 11.35mV??

Just trying to follow the thinking behind these calculations, so I can supply a similar set of values that are consistent with what's been shown.

Best,

My logic is that full screen at 2 mV/div is 16 mV from top to bottom (8 mV above and 8mV below zero). If you inscribe sinewave inside, top to bottom, RMS of that sinewave would be 16 mV/1.41= 11,35 mV.
That is full scale RMS. That is also how I understood IEEE excerpt in R&S whitepaper.

But, I agree it is beside point to call upon some standard if all conditions are not observed. And I agree that we shouldn't call it ENOB but effective resolution.
 
We could simply define a figure of merit that would  compare full scale with residual RMS and P-P noise..  It would serve well as relative comparison and would be somewhat easier to reproduce.

There were previous comparisons made, including calculating noise PSD and such...
Title: Re: Benefits of going with all Siglent setup
Post by: mawyatt on October 27, 2020, 02:25:33 pm


My logic is that full screen at 2 mV/div is 16 mV from top to bottom (8 mV above and 8mV below zero). If you inscribe sinewave inside, top to bottom, RMS of that sinewave would be 16 mV/1.41= 11,35 mV.
That is full scale RMS. That is also how I understood IEEE excerpt in R&S whitepaper.

But, I agree it is beside point to call upon some standard if all conditions are not observed. And I agree that we shouldn't call it ENOB but effective resolution.
 
We could simply define a figure of merit that would  compare full scale with residual RMS and P-P noise..  It would serve well as relative comparison and would be somewhat easier to reproduce.

There were previous comparisons made, including calculating noise PSD and such...

The RMS of a sinusoid is (peak value)/rt2, not (peak to peak value)/rt2. In your example you have a full scale 8 division sine wave at 2mv/div, so 16mv peak to peak and thus 8mv/rt2 RMS value.

Agree a FOM should be utilized and I'm all ears for what should be utilized/created for such.

Best,
Title: Re: Benefits of going with all Siglent setup
Post by: mawyatt on October 27, 2020, 03:03:47 pm
Just did a quick test of the SDS2102X Plus in 8 bit, 10 bit, and ERES (3) modes using this as a means to evaluate Effective Resolution in bits. I'm not saying this is right or wrong way, just the way I chose to measure and calculate. Used 20MHz BW with 50 ohm in-scope termination, 1us/div sweep. Noise was averaged Standard Deviation to remove DC offset effects as mentioned.

Effective Resolution Bits (ERB) = {10*log[(8*(SF/N)^2 +1)] -1.76}/6.02, where N is Standard Deviation noise, SF is Scale Factor in V/div

Scale    500uv   1mv    2mv    100mv    200mv     500mv     1v
8 bit N  23.4uv  24uv  38.6uv  1.47mv  2.95mv    7.55mv    14.56mv
ERB     5.63      6.59    6.90     7.30      7.29         7.26        7.31

10 bit N 16.9uv  17uv   20uv   316uv    432uv      1.83mv    2.32mv
ERB     6.10      7.09     7.85    9.50      10.06       9.72        9.96

ERES N 12uv     12uv   14uv     132uv    190uv      725uv     860uv
ERB     6.59      7.59    8.37     11.60     11.89      11.80      11.39

FFT NF -122      -120   -120     -118      -108        -100        -97
in dBm

Added FFT noise floor in 8 bit mode using 2.5MSPS, 2097512 pts, delta f 1.19Hz and 16 average.

I computed these on my HP32 calculator, so hopefully no mistakes ::)

Best,
Title: Re: Benefits of going with all Siglent setup
Post by: 2N3055 on October 27, 2020, 07:21:01 pm


My logic is that full screen at 2 mV/div is 16 mV from top to bottom (8 mV above and 8mV below zero). If you inscribe sinewave inside, top to bottom, RMS of that sinewave would be 16 mV/1.41= 11,35 mV.
That is full scale RMS. That is also how I understood IEEE excerpt in R&S whitepaper.

But, I agree it is beside point to call upon some standard if all conditions are not observed. And I agree that we shouldn't call it ENOB but effective resolution.
 
We could simply define a figure of merit that would  compare full scale with residual RMS and P-P noise..  It would serve well as relative comparison and would be somewhat easier to reproduce.

There were previous comparisons made, including calculating noise PSD and such...

The RMS of a sinusoid is (peak value)/rt2, not (peak to peak value)/rt2. In your example you have a full scale 8 division sine wave at 2mv/div, so 16mv peak to peak and thus 8mv/rt2 RMS value.

Agree a FOM should be utilized and I'm all ears for what should be utilized/created for such.

Best,

 :palm: |O
'nuf said.... I'm gonna go hide now...

corrected..
Title: Re: Benefits of going with all Siglent setup
Post by: rf-loop on October 28, 2020, 06:48:19 am
So if I'm not wrong my calc for MSOX3104T would go like this, for those conditions:

(Attachment Link)

and

(Attachment Link)

so that gives:

(Attachment Link)


Although ENOB is not single number, it is frequency/ENOB graph....

Shouldn't the ENOB be computed based upon a sine wave input of full scale peak to peak (8 divisions)? If so then the relative signal power would be (4*scalefacor/rt2)^2, or 8*(Scale Factor)^2.

Best,

To be honest ENOB is supposed to be measured specified with the actual signal at actual frequency, so it includes both noise and distortions in SINAD.

In this case we assume (for 2mv/div for instance) full scale P-P sine signal of 16 mV.  RMS of that (11,35mV) divided with RMS of noise (110 uV) gives 10641 ratio, convert that to dB (power ratio) gives 40,2dB,  and converted to ENOB :6,397 bit.

I did quick test with R&S method and got same results.

These tests will have major source of error in scopes built in RMS function and it's limits to deal with calculating RMS of noise and otherwise very complex signal.
 
Please correct me if I'm wrong..

Regards,

I had seen the IEEE definition on ENOB, and agree it's without signal distortion and not at a specified signal frequency since no signal is actually applied. So maybe a best case ENOB, or as Howard mentioned Effective Resolution.

From above "In this case we assume (for 2mv/div for instance) full scale P-P sine signal of 16 mV.  RMS of that (11,35mV) divided with RMS of noise (110 uV) gives 10641 ratio, convert that to dB (power ratio) gives 40,2dB,  and converted to ENOB :6,397 bit."
Since the peak to peak full scale signal would yield a sine wave of 4 divisions peak, the RMS would not be of the 8 division peak to peak value, but of the 4 division value. So this would yield 4*2mV/rt2 = 5.657mV RMS, not 8*2mV/rt2 = 11.35mV??

Just trying to follow the thinking behind these calculations, so I can supply a similar set of values that are consistent with what's been shown.

Best,

My logic is that full screen at 2 mV/div is 16 mV from top to bottom (8 mV above and 8mV below zero). If you inscribe sinewave inside, top to bottom, RMS of that sinewave would be 16 mV/1.41= 11,35 mV.
That is full scale RMS. That is also how I understood IEEE excerpt in R&S whitepaper.

But, I agree it is beside point to call upon some standard if all conditions are not observed. And I agree that we shouldn't call it ENOB but effective resolution.
 
We could simply define a figure of merit that would  compare full scale with residual RMS and P-P noise..  It would serve well as relative comparison and would be somewhat easier to reproduce.

There were previous comparisons made, including calculating noise PSD and such...

This your RMS is corrected after this original msg, so I do not take this accidental human mistake on table.

But I want ask one think.

There are these..
"My logic is that full screen...blablabla.."
Then also
"That is full scale RMS."

Not all scopes have ADC full scale same is display full height. 
Of course it do not make big difference but... small error there and other error here and there... and we talk finally perhaps big error.

Many scopes (but not all) what I have handled have ADC full scale around or over 10 vertical div and displayed part of whole vertical is 8 div. But different scopes may be different in this. 

If 2mv/div and ADC FS is  example bit over 10 div. For simplify think 10div.
In this case FS  sinewave is 20mVp-p  so 7.071 mVrms. I think there need use this ADC full scale in calculations  what is used in individual scope instead of displayed part of signal if it is different.

Title: Re: Benefits of going with all Siglent setup
Post by: Fungus on October 28, 2020, 08:40:22 am
You're right to question them, as did I at the time.

The figures are from the scope's own measurements.

Did you do a self-cal immediately before making those measurements?
Title: Re: Benefits of going with all Siglent setup
Post by: 2N3055 on October 28, 2020, 08:45:25 am

This your RMS is corrected after this original msg, so I do not take this accidental human mistake on table.

But I want ask one think.

There are these..
"My logic is that full screen...blablabla.."
Then also
"That is full scale RMS."

Not all scopes have ADC full scale same is display full height. 
Of course it do not make big difference but... small error there and other error here and there... and we talk finally perhaps big error.

Many scopes (but not all) what I have handled have ADC full scale around or over 10 vertical div and displayed part of whole vertical is 8 div. But different scopes may be different in this. 

If 2mv/div and ADC FS is  example bit over 10 div. For simplify think 10div.
In this case FS  sinewave is 20mVp-p  so 7.071 mVrms. I think there need use this ADC full scale in calculations  what is used in individual scope instead of displayed part of signal if it is different.

I agree with that and know that scopes usually have a bit of "reserve" so not all of the ADC range is "mapped" to the screen. But I was going with what is visible on screen, so if you compare two scopes side by side looking at same signal what you would get.  But as you say well, things are even more complicated. On my MSOX3000T i press vertical knob and put it in a fine mode.. I'm not going to do the detailed test  now, but you can look at the signal at 113 mV/div. or 271 mV/div.  or 7 mV/div. Is that 7mV/div really 10 mV /div software magnified or 4 mV/div scaled to 7 mV/div. It probably doesn't have real lineary variable gain amplifier (like analog ones did). Or maybe it does?

Those details would need to be available to be able to test all of it to into details.  But that even might be unnecessary to most people. They might want to know simply noise levels (or whatever specification that is important to them) in like to like scenarios for their intended purpose. Like, if I do lot of work on 3,3V logic signal, i would view it at 430 mv/div.... What is noise there, for instance ? Or I will simply use 500 mV/div to compare two scopes doing same job..

Thing is, people tend to want simple decisions. Like which scope has less noise.. and it gets complicated quick. Do they think visible noise on trace on screen? Or what AC RMS measurement is calculating..
Scopes with faster retrigger rate will visibly have it more, those with different display engine will have different, two same scope with different display intensity will have different, different  time bases etc etc...

There will be some fast truths: for instance, at 1 mV/div MSOX3104T you are looking at 4mV/div magnified in software.. And it's not as good as on a scope that has 1 mV/div real range.
BUT, you get that 4 mV/div (and its software maginification) with full 1 GHz bandwith.. So for something that is few mV and FAST, it's better than 1 mV/div with 200 MHz bandwidth limit on small ranges.
And if you're looking at lower frequencies, you enable Hires, and noise goes down, and it's nice and clean...

But all those technical details on the side, fact is that Rigol scopes with new chipset have fat traces (in X-Y mode trace is as fat as a finger), while new generation Siglents look nice and clean. It is obvious they have less visible noise on screen on lower ranges. And they also have real low ranges not software magnifications. And sometimes bandwidth limits at very sensitive ranges,or not, based on model.

So if you are doing some sensitive (low signal level) analog stuff at not very high frequencies (up to 100 ish MHz) new Siglents have better front end for that.
For looking at digital level signal, you probably won't care which one......

For my money, and for like prices, as my only scope, for instance I would go with Siglent SDS2000X+ any day instead of Rigol MSO5000 or Keysight DSOX1204. I would also buy GW Instek 2000E series before Rigol MSO5000 or Keysight DSOX1204. I tried it (GW INSTEK) and there many things on that scope I would have done differently, but I really liked what it can do. It simply works and does the job. It is more mature platform than SDS2000X+, which means more limited, and not expecting any further major development, but more stable.. Pretty much no bugs to be found.. Very much like Keysight.
ON the other hand SDS2000+ holds more promise.. It will develop further... How much, we will see..

I will draw a paralel, when in 80-ies a noname manufacturer Ibanez started making "some cheap Japanese guitars".. Or when Yamaha started selling their guitars to the west... There were also literally hundreds of other manufacturers, making very good stuff, but that got forgotten and disappeared... We are at that same era of T&M instruments. It is a bit of gamble... To those buying Yamaha and Ibanez, gamble worked well, for some others not so much..  And which one is which, only future will tell..

Regards,


Title: Re: Benefits of going with all Siglent setup
Post by: Performa01 on October 28, 2020, 09:14:49 am
Just for completeness:

The SDS2000X+ and also SDS5000X have 30 LSB/div, that is 240 steps for full screen. Very little overhead.
The SDS1000X-E (and most likely also SDS2000X-E) have 25 steps per division, hence only 200 counts full screen.

The SDS2000X+ can maintain the full extended bandwidth of 500 MHz down to 500 µV/div.

All contemporary Siglent DSOs prvide fine adjust of the vertical gain, and these are true hardware PGA steps.
Title: Re: Benefits of going with all Siglent setup
Post by: Howardlong on October 28, 2020, 01:58:22 pm
You're right to question them, as did I at the time.

The figures are from the scope's own measurements.

Did you do a self-cal immediately before making those measurements?

Yes. One reason why I mentioned I am time poor at the moment, I don't have much time available to go and re-do all these tests again.
Title: Re: Benefits of going with all Siglent setup
Post by: Howardlong on October 28, 2020, 02:59:33 pm
Please note that my table was effective resolution, not ENOB; there is a difference.

TurboTom: I do still have the scopes, but I'm very time poor at the moment.

Could you show how you calculated the Effective Resolution in your table so we can compare results on an "Apples to Apples" basis.

BTW thanks for showing the table and taking the time to post these results :-+

Best,

Here's the spreadsheet I used.




Title: Re: Benefits of going with all Siglent setup
Post by: mawyatt on October 28, 2020, 03:15:07 pm
[attach=1]
Just for completeness:

The SDS2000X+ and also SDS5000X have 30 LSB/div, that is 240 steps for full screen. Very little overhead.
The SDS1000X-E (and most likely also SDS2000X-E) have 25 steps per division, hence only 200 counts full screen.

The SDS2000X+ can maintain the full extended bandwidth of 500 MHz down to 500 µV/div.

All contemporary Siglent DSOs prvide fine adjust of the vertical gain, and these are true hardware PGA steps.

I can confirm that the vertical scale fine adjustment appears to be from a PGA on SDS2102X Plus, and not in software.

Another important aspect of the vertical input is that the trace vertical position (offset) adjustment apparently is introduced near the front end which allows high levels of DC offset from the signal source to be nulled and not saturate the postamps or ADC.

Here's a quick test DC coupled at 5m/div with a 30mv peak to peak sine wave that has a 2 volt DC offset! This huge offset correction (>50X) works at the lower scales also (>100X), but I don't know what the offset range is (takes a long time to twiddle the offset knob), so gave up after 400mv offset on the 500uv scale with a 3mv peak to peak signal!!

This is an often overlooked important feature of a vertical channel front end, the old Tek scopes got this right, but wasn't sure if these new DSOs did. In many cases you can utilize this feature instead of employing a differential probe.

To get this right as evidently Siglent has, you must introduce the offset correction well up towards the channel input front, since any prior high gain amps will saturate with a large offset, and/or the ADC will saturate. To do this requires very low noise offset correction circuitry with high resolution, so a good hi-res DAC with a low noise reference is required.

Anyway another pleasant surprise feature/capability I didn't expect with these modest $ DSOs :)

Best,
[attach=1][attach=2]

Edit to add why this input channel offset correction range is important.

Here's an example of a 1Hz 10mv peak to peak triangle wave with a 100mv offset. Note scale factor to "see" the waveform without offset correction is 50mv/div DC coupled.
[attachimg=4]

Now introduce AC coupling and change scale to 2mv/div
[attachimg=5]
Yikes, that's not a triangle waveform :o
With AC coupling this become the derivative of the input, and the derivative is a squarewave ???

Now use DC coupling and the offset adjustment to null the 100mv input offset ;)
[attachimg=6]
That's certainly looking better :-+

Best,


Edit: Sorry I can't get the images into the text flow, they just all show up at the bottom no matter what I try :P
Title: Re: Benefits of going with all Siglent setup
Post by: mawyatt on October 28, 2020, 05:23:16 pm
Please note that my table was effective resolution, not ENOB; there is a difference.

TurboTom: I do still have the scopes, but I'm very time poor at the moment.

Could you show how you calculated the Effective Resolution in your table so we can compare results on an "Apples to Apples" basis.

BTW thanks for showing the table and taking the time to post these results :-+

Best,

Here's the spreadsheet I used.

Thanks. If I interpret the spreadsheet correctly you are using Effective Resolution Bit as Log(FS/N)/Log(2) and not the standard ENOB of (SINAD -1.76)/6.02, where in our case SINAD would be 10*Log(FS/N +1) using RMS values and no distortion term, since no input signal is actually applied.

Using what I did which includes the ADC quantizing error term but no distortion term I get similar but slightly 0.3 bit lower (not surprising since 1.76/6.02 ~0.3 bit) results, for example.

MSO8104A
2mv        5.26     vs.   5.55
100mv     6.71    vs.   7.01
200mv     6.71     vs.   7.01
500mv     6.74     vs.   7.03
5V           6.70     vs.   6.99



Best,

 
Title: Re: Benefits of going with all Siglent setup
Post by: RBBVNL9 on October 28, 2020, 05:29:22 pm
Back to the original question...

Quote
Other than the brand look and feel and having similar interfaces (I would hope) are there other advantages of going with the same manufacturer?

I have several Siglent 'x' devices, but they do not really have the same look and feel, as you (rightfully) hope. Their user interfaces differs in many ways, and the 'deeper' you go (e.g. configuring the communication interfaces), the larger the differences. While the screens with their underlying 5 or 6 soft buttons suggests a consistent UI approach, this is not the case, and the overall button 'logic' varies. Physical button placement varies quite a bit. For instance, the SDG AWG and SDL electronic load both have 10 digit keypads, but they keys are just the other way around. Also the PC software for these devices seems to have nothing in common, entirely different programs. Some have 'real' on/of buttons, some soft buttons. The cases stack reasonably well, but as others have noted, their depth is sometimes different.

Having that said, I selected them for what I needed for specific use cases, and feel happy for what they do at their price point. They are quite nice devices and I would buy them again.
Title: Re: Benefits of going with all Siglent setup
Post by: Howardlong on October 28, 2020, 06:33:49 pm
Please note that my table was effective resolution, not ENOB; there is a difference.

TurboTom: I do still have the scopes, but I'm very time poor at the moment.

Could you show how you calculated the Effective Resolution in your table so we can compare results on an "Apples to Apples" basis.

BTW thanks for showing the table and taking the time to post these results :-+

Best,

Here's the spreadsheet I used.

Thanks. If I interpret the spreadsheet correctly you are using Effective Resolution Bit as Log(FS/N)/Log(2) and not the standard ENOB of (SINAD -1.76)/6.02, where in our case SINAD would be 10*Log(FS/N +1) using RMS values and no distortion term, since no input signal is actually applied.

Using what I did which includes the ADC quantizing error term but no distortion term I get similar but slightly 0.3 bit lower (not surprising since 1.76/6.02 ~0.3 bit) results, for example.

MSO8104A
2mv        5.26     vs.   5.55
100mv     6.71    vs.   7.01
200mv     6.71     vs.   7.01
500mv     6.74     vs.   7.03
5V           6.70     vs.   6.99



Best,

 

Yes, as I stated before, effective resolution isn’t the same as ENOB. As you say, effective resolution gives an apparently “better” result than ENOB.
Title: Re: Benefits of going with all Siglent setup
Post by: mawyatt on October 28, 2020, 06:51:11 pm
Back to the original question...

Quote
Other than the brand look and feel and having similar interfaces (I would hope) are there other advantages of going with the same manufacturer?

I have several Siglent 'x' devices, but they do not really have the same look and feel, as you (rightfully) hope. Their user interfaces differs in many ways, and the 'deeper' you go (e.g. configuring the communication interfaces), the larger the differences. While the screens with their underlying 5 or 6 soft buttons suggests a consistent UI approach, this is not the case, and the overall button 'logic' varies. Physical button placement varies quite a bit. For instance, the SDG AWG and SDL electronic load both have 10 digit keypads, but they keys are just the other way around. Also the PC software for these devices seems to have nothing in common, entirely different programs. Some have 'real' on/of buttons, some soft buttons. The cases stack reasonably well, but as others have noted, their depth is sometimes different.

Having that said, I selected them for what I needed for specific use cases, and feel happy for what they do at their price point. They are quite nice devices and I would buy them again.

This is an area where Siglent could make significant improvements. I can't say about Rigol and others since I don't have that equipment, but also have 3 different Siglent instruments and they are not generally consistent.

Likely why they will not make significant in-roads into major electronics companies because;

A) The equipment decision makers are older and tend to use tried and true instruments they know and have experience with.

B) The cost of learning a new interface can often exceed the instrument cost, so a more expensive user friendly known instrument may cost less in the long run.

C) Calibration (if required) is well known and established for "Brand Name" instruments, but may be spotty for unknowns.

I know these from prior experience, and made decisions on Tektronix & HP based upon such. Most new equipment could be quickly placed into service without lengthily manual studies or unproductive fiddling. When the engineering cost can range from 200~$500/hr in IC fabless design centers, and even more for IC fab facilities the actual cost of a new instrument can often be evaluated by it's learning curve and not it's direct initial cost.

Siglent should take note of this uniform UI experience if they expect to move up the instrument food chain.

BTW one clever way HP/A/KS ( and Tek, R&S) to get exposure to younger EEs was to supply the University labs with the latest equipment, this way grad students were exposed before they graduated. 

Best,
Title: Re: Benefits of going with all Siglent setup
Post by: RBBVNL9 on October 28, 2020, 07:20:54 pm
Quote
Siglent should take note of this uniform UI experience if they expect to move up the instrument food chain.

Totally agree. Not only may that - slowly - position them more upwards, but also make them more appealing across a wider base of users from diverse profiles.

Addressing the learning curve is important in places where hourly wages are high, but also in teaching environments (e.g. universities) and other places where the users are diverse, frequently changing, etc. 

Quote
The equipment decision makers are older and tend to use tried and true instruments they know and have experience with.

Sure. But if the Siglents etc. are wise, they would realise that their current adopters might be the 'older' men in the future that specify instrument acquisition/procurements. The older brands already realise this, they offer educational discounts not because they are charities, but because they know it will lead to more sales on the longer term.

Finally, also having a well developed Microsoft Windows and MacOS software environment, supporting all instruments from within the same, easy to use software package, would make more people lend towards new purchases from the same brand. Some of the current software hardly seems to be beyond the Beta stage, if not before, with terrible installation procedures. And it seems that for every device, they are redeveloping new software from the ground up - an expensive development' I'd think.

Finally, a device we a well developed UI is also a pleasure to work with, something that invites you to take it up again and use it.

Much if this could even be done by firmware updates for existing devices, and PC/Mac software development.
Title: Re: Benefits of going with all Siglent setup
Post by: mawyatt on October 28, 2020, 07:25:30 pm
Please note that my table was effective resolution, not ENOB; there is a difference.

TurboTom: I do still have the scopes, but I'm very time poor at the moment.

Could you show how you calculated the Effective Resolution in your table so we can compare results on an "Apples to Apples" basis.

BTW thanks for showing the table and taking the time to post these results :-+

Best,

Here's the spreadsheet I used.

Thanks. If I interpret the spreadsheet correctly you are using Effective Resolution Bit as Log(FS/N)/Log(2) and not the standard ENOB of (SINAD -1.76)/6.02, where in our case SINAD would be 10*Log(FS/N +1) using RMS values and no distortion term, since no input signal is actually applied.

Using what I did which includes the ADC quantizing error term but no distortion term I get similar but slightly 0.3 bit lower (not surprising since 1.76/6.02 ~0.3 bit) results, for example.

MSO8104A
2mv        5.26     vs.   5.55
100mv     6.71    vs.   7.01
200mv     6.71     vs.   7.01
500mv     6.74     vs.   7.03
5V           6.70     vs.   6.99



Best,

 

Yes, as I stated before, effective resolution isn’t the same as ENOB. As you say, effective resolution gives an apparently “better” result than ENOB.

Don't think it really matters as long as all comparisons are done using the same methodology and calculations. ADCs and DACs have a long history of confusing and not directly applicable specs that caused all kinds of havoc for designers. I recall almost 40 years ago some Sony 10 bit DACs that were designed for high end TV RGB displays actually performed better than 12 bit and most higher order DACs when used at RF frequencies. When folks starting using ENOB with specified frequencies things got much better for the design engineer instead of the usual sample, try and test approach. I know we were asked many times about why we were using only 10bit Sony DACs, and not higher order types from well known sources, the simple answer was they are better and we measured them :o
Title: Re: Benefits of going with all Siglent setup
Post by: tautech on October 28, 2020, 07:38:27 pm
FYI a large # of the DSO range has the same 'look and feel' which started with a new UI in the now dated SDS2000 which was then adopted into X model DSO's, SDS1000X, SDS2000X and later into SDS1000X-E and SDS2000X-E.
All these scopes have a very very similar UI.

SDS2000X Plus and SDS5000X are newer and completely different UI ventures that the SDS6000 Pro also shares if we ever get to see them in the west in other than in LeCroy colors.
Some front panel layout consistency was maintained in SDS5000X to previous ranges however SDS2000X Plus has modifications to group lesser used buttons away from the everyday use ones. These small front panel changes have also been adopted in the SDS6000 Pro.

X models in all the product lines have different UI's from previous product incarnations where the earlier AWG for example all had the same basic UI. This is unchanged albeit with a later X UI version in the current X model AWG range.
Title: Re: Benefits of going with all Siglent setup
Post by: Fungus on December 18, 2020, 09:00:55 pm
It is however possible the Vrms calculation in the MSO5000 is wrong  >:D

It's also possible that the Siglent is wrong and that the real Vrms figure is higher.  :popcorn: