REVIEW - Owon SDS7102 - A look at the SDS series from Owon

[IanB]

Yuk, that Owon front panel looks cheesy! It looks like some kind of Fisher-Price toy 

[saturation]

I recall marmad said the same during his review, but its what's inside that counts.

Until marmad's review, the Owon had no real following on eevblog, at least, and made it one of the better low end scopes to consider.  For comparison, there is an Atten scope in this performance range that did not do well with a performance review.

Yuk, that Owon front panel looks cheesy! It looks like some kind of Fisher-Price toy 

[tinhead]

SDS7102 with LAN

hey, i have a nice gift for you, see attached.

Use both of them and shot some pictures of the PCB and LAN

[rf-loop]

SDS8202 samplerates in fast horizontal speed area 1ns - 50ms/div
Slow speed horizontal speed area 100ms - 100s/div not included here.
(also notice that low speeds are divided two different modes. As normal capture mode and scan mode(default))

Of course this table is valid to both 2Gs/s models. SDS8102 and SDS8202.
Difference with these models are only analog BW.

[tinhead]

these values are really bad ... in deeper mem no difference to SDS7102,
not worth to pay extra money as the SDS7102 bw is already 140MHz

these values are not bad - Rigol CA have always max. 2 x 5k while on 2GSs,
Owon SDS8xxx  max. 2 x 10k - that's twice the Rigol depth plus a 10M bonus when sampling
with 1GSs. Additionaly higher bw than on Rigol CA, not much but ask your wife - 5cm more is a lot

take the one you like .... actually i'm not surprised that Owon (once again) lying about such important feature,
but well, we know that other manufacturers are not better. I hope some day ppl will learn the difference
between "up to" and "of", because it matter.



@rf-loop,

when you have time please measure bw of SDS8202, i think it will be something like 250MHz

[rf-loop]

@rf-loop,

when you have time please measure bw of SDS8202, i think it will be something like 250MHz

Yes it is nearly.
But as we well know, more and more high freuency and impedance matching go more difficult.
0 - 100MHz with this kind of input is not big problem to match with 50 ohm terminator connected to input.
(if take signal directly from 50 ohm source via 50 ohm cable.) Of course problem start littlebit but not bad.
100 - 200 MHz and problem is more bad. Over 200MHz it is so bad that what we test.. our signal road or oscilloscope itself.

It is pity that this kind of scope do not have 50ohm impedance inputs. (I do not mean that terminator resistance is inside scope. I mean impedance 50ohm for this whole frequency area.

If look only one example. 15pF reactance at 200MHz frequency is around 53ohm. If forget all other things in practice there is 50ohm terminator and parallel with it 53 ohm reactance. Simply: I can not simply measue oscilloscope itself frequency response becouse I have not well matched feedline to oscilloscope. If I do it, I measure whole system response only. With 100MHz it is also there but error is "acceptable".
With extremely bad matching, 50ohm terminator connected to oscilloscope input (1M, 15pF +-5pF) I can see that scope show -3dB point around > 230MHz. (this is not scope response, it is system response what is more bad than scope itself... and here around >200MHz this error in measurement come really markable)

-----------------

This is not for Owon. This is for ALL manufacturers today. And littlebit more to Asian manufacturers.
They must not hide specifications. They can sell one machine. People read specs and ads and then he have "waiting value" that it works as he have dreamed after he have  read machine introduction/ad.

Now if it do not work as he have dreamed it is big disappoint and around of world or with himeself he talk how bad it is - just becouse he was dispappointed. Maybe machine still work and is just ok to what he need  but becouse he was dispappointed his feel is "this machine is peace of bullshit".  Maybe he feel fooled and also this Company is bad lyer in his mind.
 
Please peoples, do you homeworks. Study how to read datasheets, if it is cpomponent, multimeter or oscilloscope and go to look mirror.  First study basic low level things how stuffs work, then read lot of material how professionals teach how to read datasheets in professional use for designing and how important are also application notes and also all these small note texts just as in insurance deal papers.

After all you still read ads and specs, nice pictures and so on. manufacturers do lot of introductions and maybe also copmare they machines to others. These are many times so biased and they find most nice way to compare so that they own looks ten times better. Well known case is this HP - Tektronix game (specially with oscilloscopes)
(look specially what they do not tell... do not come blind after they talk what they want talk - watch carefully and deeply what they do not tell. This is sometimes maybe most important thing to find)
Try to find Agilent papers what tell exactly memory depth and samplerate it use with different settings (you can not find) and what it can or can not use. (example after you read this wfrms/s bullshit or half truth. yes they do not not exactly lie but... 

I think  some manufacturer may win who is honest and who do not give peoples feel disappointed and fooled.
Who is first who understand this -- and also... do it in real worlkd!

I want be one small small part of this system what teach this to Chinese. They can win in end if they want. But what they need start. They need start learn how to be more open. How to be honest. This old culture of clever smart seller who can sell chickens with heavy rocks and stupid buyer need stop. Everyone can be smart seller and fool someone to buy and win his money - but he can do it only once with this buyer. World is now different. It works in old world where you move 5 kilometers and then you are agen new unknown. (or in big city it need 500 meter.)   

With test equipments this may win who publishe most accurate and deep specifications and also real specifications. Not copypaste specifications from other manufacturers.

It was how Tektronix win tens of years example world of oscilloscopes.
There was even full detailed description and theory about inside circuits and full and updated schematics and service manuals etc.
No one copy these so that it is bad for Tektronix. No one. Why?

Owon grow in good tree... it is like raw apple. If they want, they can be better.
They need do some small things and one of these things are good and hinest specifications where people can exactly see what he buy... then he is not disappointed with his own developed dreams becouse there are not enough facts. (this is natural for peoples mind and it can also work opposite, you can hate something just becouse lack of knowledge. But you can also hate something if this something have destroy your own itself developed dream what was possible becouse lack of information)

After disappointed or feel like fooled.. peoples write they opinion. Many of these opinions may very easy destroy one name... or seriouslu damage it. There are thousends of peoples who have not write any opinions. Also in this unsocial media if peole is angry and disappointed he open more frequently his mouth as this kind off people who feel neutral or satisfied.

So, what I hope.

I hope some Chinese manufacturer start develop themselves. Owon is one good candidate.
Littlebit quality and reliability developing, littlebit more thinking for UI useability.
And accurate information about features and specifications.

Do not afraid and ashame specs details as they are. Truth can not really hide. If some detail is not so good please tell it also. If you hit information you give,  with lack of information, that people can develop some "dream"  that it have this or that feature. Then if he buy and there is not what he have dreamed...  you maybe have get his money -- "fished and get his money"  yes you are smaryt and clever Chinese business you can fish money from "stupid" poor educated buyers.

But if he is not in your boat and he is disappointed only becouse lack of information or even you have littlebit lie or as white lie information....
He may have to pour your fishing boat if he is not in the same boat with you.

So, if Owon or who ever manufacturer want win. Start develop design quality, quality control, start be more open mind and stop this shy and hide with specs. Real honest specs to table - please,  and if do it right way - you win and customers win and both can smile.

Owon is not bad, it is one of most good oscilloscope in this price class. It give not se many dingle dongle features but it is good  DSO. 

Today with this FW and/or HW this SDS series maximum samplerate with more than 10k/channel memory is 1Gs/s.
If we talk SDS7102 alone it have deep memory with full maximum samplerate 1Gs/s with one channel  or 500Ms/s with two channel in use. This capture memory is selectable from 1k to 10Mpoints. Both channels have  max 10M capture memory (not divided memory

SDS8102 and 8202 have not deep memory with full 2Gs/s.  Maximum to deep memory is 1Gs/s with single channel or 500Ms/s if two channel in use.

With 2Gs/s in single channel use and 1Gs/s with two channel use there is 1k and 10k capture memory.
(in FW it is nice that if use fast horizontal speed and it use 2Gs/s then if you select more memory you can do it. It drops samplerate. If you agen select 1 or 10k it return this 2Gs/s. And becouse it always show samplerate on the display you always know what it is doing. (exept with low speed area if scan mode is used... there display show (this is bug) totally wrong samplerate, if slow speed mode (100ms - 100s/div)  use normal or singleshot mode (not scan mode) it diplay right samplerate.

[rf-loop]

@tinhead

as you ask 8202 freq response. Now measured but note what I before write about matching.

With one thru in 50ohm Tektronix terminator:

Reference freq 1MHz
Scope set to 50mV div, dc. One channel in use.
Signal level so that it is 300mV p-p with 1MHz. (6 div on scope display)

-3dB point: 240 MHz
-6dB point: 306 MHz

same test with SDS8102

-3dB point: 126 MHz
-6dB point: 240 MHz

same test settings continue with SDS7102

-3dB point: 146 MHz
-6dB point: 280 MHz

(all scopes are littlebit individuals and becouse with this very bad matching this give quite small variations in scope input capacitance (and other things)  affect "lot of" to result.
If need working with high frequencies/fast risetimes with scope what have no real 50 ohm impedance input for whole useable frequency area, this need taken into account. it is possible to make better matching but it is nessesary in only some special cases. With this can live but it need know so that understand what is difference between real world and measured world. )

[0xdeadbeef]

Little update from my side: while my dealer was neither able to provide me a firmware update nor other clarification up to now as he says his contact person at Owon is ill, he offered me a 100€ refund if I keep my 8102 instead of downgrading to a 7102. Which is kinda fair I think. Then again, let's see how this works out.
As a side note: as usual when I buy something, the prices for both models dropped by 30€ since I bought my Owon there, but yeah well.

Furthermore Owon contacted me today and sent me a (awfully slowish) link to a 85MB download which contained a new version of the oscilloscope SW (2.0.8.1) and a firmware patch tool. Before you ask: the patch seems to be encrypted or signed specifically for my serial number. I guess this proves that the reason for not providing a download link really is the fear that another manufacturer could disassemble and/or clone their firmware. I'm not so sure that this concept really works, as firstly Atten seems to have already cloned the MSO/new PDS line and secondly, there is a public key in the patch folder. If it's used in the decoding process and not just to sign the firmware, decrypting it should not be so complicated.

Anyway: so I followed the update instructions, at the end the tool told me the update was successful, but honestly after rebooting I couldn't see any difference. The scope still refuses to save files >7kb on a 16GB Fat32 stick, while an 8GB stick works. Using Autoset in the FFT setting still crashes the scope. And most importantly, the Utility-About dialog still shows a "v1.0".
So there are two possibilities: either the update failed or the About dialog shows some version number, but not the one of the actual OS. Since the update procedure looked ok to me, I tend to believe there is a bug in the version display or maybe in their (SW) build process. Probably the ABout dialog is stored in one of the text files that tinhead mentioned and that text file is not always updated correctly.

So while I can't see really an improvement in the firmware, the new "Oscilloscope" (windows) SW seems to be able to read the small (7kb) waveform files saved in scan mode now. Apart from that, it's as bad as before. Then again: the fact that I can save working (albeit very small) waveforms in scan mode seems to strengthen the idea that the SW version is really much newer than the About screen suggests. Or should the scope save large (10M) waveforms also in scan mode?

[tinhead]

Since the update procedure looked ok to me, I tend to believe there is a bug in the version display or maybe in their (SW) build process. Probably the ABout dialog is stored in one of the text files that tinhead mentioned and that text file is not always updated correctly.

right, the updates i saw are only application updates (Owon calls it "osc" or "os"), non of the text files are included in update files
(no reason why, maybe they just don't want to increase version numbers to hide the update count? no clue) so you will
not see any version change.

When you would made NAND dump before and after update you would see that some content has been changed.

[rf-loop]

Scan mode use very slow samplerate.
Scan mode is just for eyes if you follow some slow things just as paper roll plotter.
If you want full resolution with low speeds.
Do not use Scan mode.
Auto trig swithch scope to scan mode.
Normal and single switch it to normal mode where samplerate is just as info on the screen.
Still they have not repaired this scan mode wrong samplerate memory info on the display info field.
---------

If update process go right:

First update software window show that it transfers data. After it show that update us success... then automatically scope continue booting.

As you see first you turn scope on (update process) scope stops to boot screen. After update process is ok it continue booting itself. If it do not, it have maybe not really updated.

(You write "after reboot"... did you mean that you need reboot unit after update process.. in success update process it boot itself.)

How to update.
Install update soft and install drivers.
Connect scope.
Let it finish all drivers istall.
Do not continue pressing update (right button).
Shut off scope.
Press right button (update go to waiting state)
Start scope. After it see scope it transfer file. (scope is stopped to boot screen in this phase)
After some time scope install update and then it continue booting.

With some mysterious reason update process do not always go ok even if software info success.

---------
If you can please give me link for update package.

(maybe I can look if there is some change in sampling or sampled data handling if my 8102 accept it - I think it accept...it is (AFAIK) not locked to your serial number.
What is 4 digits on your serial... do not tell whole serial.. I mean these marked as YYZZ... example SDS8102YYZZxxx) (this serial part is not also needed for update but I try look what are manufacturing datecodes and versions they have used.

This info please only PM (not public)

[0xdeadbeef]

@tinhead: ok thanks for confirmation. The actual update file inside a (renamed) ZIP file called "bundle" is named "os".
Obscuring the firmware revision seems to be a pretty weird strategy though as it makes it hard for the support to actually tell which firmware someone uses.

@rf-loop: indeed the software tells me "Transmit done, wait for machine process..." and then "Rebooting machine. Patching is done!", but then the scope stays in the boot screen.
So maybe the patching actually failed despite of the success message, but I tried it now a dozen time and the behavior is always the same. I even tried different USB ports.

Regarding the patch SW: in the main installation folder, there is a file called "model" which contains the string "osc" and my complete serial number. There also is a file called public.key which contains 16 bytes and which obviously contains a 128bit public key. So I severely doubt that this update will work on another scope. For the other stuff, I'll answer via PM.

[rf-loop]

in the main installation folder, there is a file called "model" which contains the string "osc" and my complete serial number. There also is a file called public.key which contains 16 bytes and which obviously contains a 128bit public key. So I severely doubt that this update will work on another scope. For the other stuff, I'll answer via PM.

Ok then it is different what I have for 7102.
File (osc) is 12 bytes and do not include direct serial number (but it include 37 prefix from serial number what is somehow related to product revision... (becouse 28 and 37 have different power supply and maybe other small differencies)

And with same package have updated several scopes. (not serial number locked)

I have sometimes see this happend that scope do not continue booting and still it have updated. But mostly it boots (but take littlebit time)

Some very short time ago they have updated this PC software on the Owon side downloadable. (size have changed but here it is nearly impossible download... <1 - 3kb/s..  so I can not check what version is there now)

[0xdeadbeef]

Mine never ever reboots, but always stays in the bootloader. I.e. I can reprogram again and again without turning off/on.
For the other stuff, check your PM.

Besides, by chance I stumbled over some more relabeled Owons:
http://www.peaktech.de/produkte/kategorie/digital-oszilloskope.html

Funny thing is that they changed the front panel sticker to a blueish tone.
http://www.peaktech.de/produktdetails/kategorie/digital-oszilloskope/produkt/peaktech-1255.html?file=tl_files/products/1001%20-%202000/1255_L.jpg

[rf-loop]

Funny thing is that they changed the front panel sticker to a blueish tone.
http://www.peaktech.de/produktdetails/kategorie/digital-oszilloskope/produkt/peaktech-1255.html?file=tl_files/products/1001%20-%202000/1255_L.jpg

Just ugly. Maybe someone can make pink and olive. Just as childrens toy.

[0xdeadbeef]

In the meantime I figured out what the problem is with saving files >8kb to my 16GB FAT32 formatted USB stick.
As I already assumed, the problem only occurs for cluster sizes >=8kb, which Windows automatically selects for partitions >8GB.
Under Win7 however the cluster size can be manually adjusted and when adjusting it to 4kB, the 16GB stick works as well.
It seems that the SDS line supports only a 4kb cluster size and fails on every cluster size >= 8kb. Yet I checked it only for
4kb (works) and 8kb (doesn't work). I'm pretty sure though that 16k and 32kb cluster sizes won't work as well.

[rf-loop]

Development evolves.

Picture quality is bad after camera jpg etc...
But it tell all what I want tell.
They have developed...

Also slow speeds 100ms - 100s/div deep memory wave save works and now also new PC soft can open these slow speed mode saved .bin files and of course they can also convert to .CSV

(Scan mode maximum samplerate is 2ks/s and memory depth small. (thi is as roll paper plotter) In this mode display info about Mem and speed is wrong. Normal and single shot mode slow speed mode samplerate and memory display is ok.)
Normal and single is full speed with full memory area useable.

Now you can name files. By typing free text.
(V2.2.1)

[0xdeadbeef]

Hm, whatever the version of the is that Owon gave me, it doesn't seem to contain any means to edit the file name. Or is there a trick how to get to that menu...

BTW: yesterday I noticed that there is an update for the Zeroplus Logic Analyzer Software which contains a DSO stacking features that also supports the Owon SDS line (the 7102 is named explicitly). Unfortunately, the SW crashes when trying to access the scope. Dunno if this is an 8102 problem again...

[rf-loop]

This 2.2.1
Is new 7102 version! Not 8000 series.

[0xdeadbeef]

Sure, but in a "normal" SW development process slightly different HW platforms would be either directly supported by the same software or the software would at least share 99% of the source code and would be e.g. configured by compiler switches.
So it's hard to understand that a brand new software for one device lacks features that the software for the other devices has when these features are in the "common" part of the software.

BTW: how do you tell which version the update has? It doesn't seem to be documented in the patch folder and it's not displayed in the scope either.

As another side not I got a confirmation from Owon that
- the firmware version displayed is not updated
- FAT32 cluster sizes >4k are not supported (and they don't seem to be willing to fix it)
- the Autoset function crashes the scope in the FFT view (and they suggest not to use it )

Dunno if this was just a mistake, but regarding the FFT they told me that: "... can be solved by upgrade that we'll have a new software for this on our website.". Maybe they are reconsidering their update policy. Would be a good idea indeed.

[rf-loop]

With who you have talked?
Owon China?

Yes they have update for PC software on the internet.

This do not solve any problem inside oscilloscope.

[0xdeadbeef]

With who you have talked?
Owon China?

Yep.

Yes they have update for PC software on the internet.
This do not solve any problem inside oscilloscope.

This remark was related to the bug in the scope's FFT function. To quote the full sentence:
"pls do not use AUTOSET in FFT mode-----which can be solved by upgrade that we'll have a new software for this on our website."

To me this sounds as if a new scope software which fixes this could be available from their website...

[rf-loop]

Owon do not have any FW updates for oscilloscopes for public share on they internet sides.
So this was reason why I ask: Do you really have talked with Owon China?

Ok you have talked with Owon China but now there is some problem. Maybe people who have answered to you did not at all understand you. Also people who answer there as "firs line" is not at all technical people.

-----

UI for scopes are nearly same over SDS models but different models have different HW and so also different FW.

New SDS7102 versions have V2.2.1.
Example marmad who make review did not have this. It was old version.
(Also V2.1.1 may be without small "bugfix patch" or patched IF seller or end user have patched it)

Now this V2.2.1 have still some minor bugs but just as "patced" V2.1.1 two "fatal" bugs have repaired  and some other small changes just as this feature for naming files. (also maybe some other things but becouse lack of time I have not enough tested to find others.

-------
This is not Owon problem:
This is Common problem. I have not seen Rigol, Atten, Hantek, Uni-T, GW etc published any good log about changes.

Years ago Agilent and Tektronix do it. There come even update sheets  to schematics.

It seems that most China manufacturers do not understand or some other reason they do not publice any kind of "changelog".  If there is different versions it is very important that there is some knowledge about fixed things and added features. I know it is difficult to show that there have been mistakes etc but... still I think it is better to be honest and open. In long run this is win-win if do this.

[0xdeadbeef]

Still it is a pretty bad idea to provide people with updates that don't have any kind of version number and keep the version number displayed in the scope not updated as well. This creates all kind of confusion and is counter productive especially for the Owon support since their customers can't even tell them which firmware they really have.

About the update at the website: I'm aware that support people sometimes give wrong answers or give answers that could be misinterpreted. That's why I said "Dunno if this was just a mistake" before mentioning it.
Then again the person who gave the link to the update also wrote this sentence about updates on the website. So you never know. Maybe enough people complained during the last weeks so they decided it makes sense to give up that stupid update policy.

[rf-loop]

repair patch do NOT need be different FW version.
Also it is possible that different HW need some repair (FW repair) but still FW version is same.

Maybe they can take this whole version information away from normal end users.
If I am manufacturer I do just this. End user do not need this info. He need only know how to use oscilloscope and what different specs and features it have. Compare old Tek where was not any software things.

I know many 465 versions, really different.

Front panel read. Model 465.
There are some minor specs differencies, whole inside have changed (nearly) maybe also some functions work better.

But what user know. It is model 465 and thats all.

But maybe mister Bill Gates teach us that allways need update and change and thousends of versions and subversions and sub repair versions etc.

I buy Toyota. Model xxxx.
It is bad.
Service do many modifications and changes and even maybe some inside software changes.
What I need know. I need know how it works and thats all. I do not need version numbers etc.
Maybe my Toyota is model xxxx and now it  have repair patch... I'm interenting only that I can do my works with it. Thats all what I need know. If there is problem - oh yes there is many - I do not like this and that and something is bad and something is nice..   If it do not work or some fail, I drive it to service. If they change something or upgrade something - I'm interesting that it works and I can do my works. If I can not - maybe I have selected wrong tool (car is tool to me, just as oscilloscope) to my needs.

My spectrum have something like 02.04.04 FW version. There is lot of later versions for same model. Why I need update. No I do not need. It do all what I want and need just as it is. I'm not interest to get new FW. Why, becouse it do all what I need. Yes there are some bugs even it is Rohde&Scwarz.. I know how I can do FW "crash" but why I need do it... I can avoid this procedure with knobs and buttons.

My mind with this update policy is just splitted to two kind of thinking road.
I do not know exactly which is better.
I can not say Owon is stupid becouse they do not put FW's to public downloadable.
I do not know they reasons. So I can not tell they are stupid. Maybe they are very clever ... if I know these all reasons... it is also possible they are just clever. But this I do not know.

[0xdeadbeef]

Sorry, but your examples are somewhat misleading.

Of course I don't need to know the SW version of my car's engine control unit because I can't update it on my own anyway. And I don't call support when my car doesn't work, but I bring it to a garage.
In a garage though, they can of course read the HW and SW revision from my ECU. And of course they will do a field upgrade when necessary. So in this case the guy in the garage is the user and it would be as dumb to hide a SW revision from him as it is when Owon is hiding it from me.

Also, of course if a (simple) device is working perfectly, I don't need firmware updates. I don't need fw updates for my mouse or LCD monitor, but many of the technical devices I bought over the last years are either so buggy or leaving out so many functionalities in the first SW revisions, that updates are necessary to make the product usable and worthwhile. There are even system that need updates because the world around them changes after release. E.g. DVD burners need a new media database or revised burn strategies and operating systems etc. need updates to react on security issues.

So the idea of perfectly running complex system is simply not true any more. And as long as my Owon freezes and crashes in certain situations, it's certainly not perfect. And apart from the bugs, there are quite a lot of functionalities that are kinda crippled and could be more or less easily fixed or improved (e.g. saving two channels at once or triggering on both rising and falling edge).

In a nutshell, there is no reasoning that could convince me that this approach of showing dummy fw numbers is not extremely stupid. There is no reason whatsoever to display a wrong (!) firmware version and Owon guys are shooting themselves in the foot with this approach.

Also, there is no reason for not making the firmware update freely available. If they wanted to protect their firmware, they miserably failed by decoding it on the PC before sending it to the scope. By reading the public key from a accordingly named file in the patch folder, they kinda invited hackers to use the patch tool for their own software encrypted with a different private key. So instead of hiding their firmware updates, they should have put a little more thought into their update process.