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

[aghp]

Hi, I have just bought SDS7102 with serial number SDS71021149xxx. I checked it like describe rf-loop.

From Image1 and 2 we can see clearly that my unit have problems.... but when I left BNC sockets open (without terminators .. see Image3) the both channels were the same?? 

I’m going to send it back to service and I’m pretty sure that they will checked it without using terminators.

This problem is fully examined and solved before. Your unit have exactly this "CH1 noise problem".  Your case, the problem is quite clear. There is no doubt.

This problem was in early phase after Owon made this new improved version. There is mistake in construction.
Sometimes it do more, sometimes less level this problem.

If your Owon service do not regognize this problem they are not Owon service at all.
Every Owon service know exatly this problem and they can easy repair it. Also you have seen this small "manual" for this repair what I have made.

If you send it to Owon itself, please write note. "This unit have CH1 noise problem"
If you send it back to some other write more this: "This problem is well known in Owon, please contact Owon service engineer if you do not regognize this problem".

Illustrated guide for repair is here: http://www.box.com/s/pvg1dqtdonx192p4os0m



http://owon.forumup.com/

If you have new Owon SDS7102 with LAN and it have serial
SDS71021143xxx - SDS71021151xxx
(exept if you have purchased it from me = sure it do not have this issue!
-- all units I sell have been in full tests and QC in my lab)


Please check if CH1 have special noise problem.
(you can find english explanation example in EEVBlog forum)

Inside Finland, locally, I can also repair it as Owon service.
Becouse I have not sell it The price of labor is a small nominal charge.

If you want do it your self and you understand that warranty may void after your own work I can give simple instructions how to do it. It is fully mechanical work and no need solder anything.

These two last sentence are for people who can not use or not want use Owon warranty if there is some individual personal reasons.  But remember, after self repair you are responsible. Example ESD may damage so that after repair unit work normally but after some weeks or even after months it suddenly fails.

But first:
1. Ask your seller what to do. (and explain that this problem is well known inside Owon factory)
--if they promise themself repair it it is ok, if they only "change" unit it is not ok becouse all units inside this serial number area may have or have this problem more or less.
2. Ask Owon directly.


-aghp

[kkawula]

Ok., thanks:) I have already written to Owon and to my seller. I hope they will send it to professional service, If not I will simply return it and look for new seller.
Once again thanks. Btw are You selling Owon scopes in Europe or only locally?

[aghp]

Ok., thanks:) I have already written to Owon and to my seller. I hope they will send it to professional service, If not I will simply return it and look for new seller.
Once again thanks. Btw are You selling Owon scopes in Europe or only locally?

In Europe, EU area.
In EEVblog you find this information here.

--------
note:

There may be some unexpected delays now in Owon service becouse they are arranging some customer services and they have  lot of problems with some chinese email services.
They are changing some things  to HongKong but seems it do not yet work well.
Also Owon official internet side have changed: OWON official side is now:

http://www.owon.com.hk/

It have officially changed around week ago.


-aghp

[Nermash]

Looks like Owon released new version of update software, now supporting older HW revisions of SDS7102 with the latest 2.5.1 fw.

[lavo-1]

  Good one Owon

Owon seem to get some bad press on here from the Rigol Mafia.
True the early Owon versions had some real bugs but I think that early Rigol models and the ongoing issues with the Hantek go to prove that they are what they are...lower end equipment and thus you must be prepared for some bugs and performance short cuts.
What I do like about Owon is that they seem committed to getting there customer support right. They have consistently updated the FW and even improved the HW on the latest models. They seem to me, to be trying their hardest out of all the Asian brands to get it right, which is refreshing.
I think the Youtube review of the early SDS7012 by a well known member on here hasn't helped Owons cause, I just wish he would use his obvious in depth knowledge of scopes, to review the updated version which I must admit I love and own.
If you are in the market for a low-mid end DSO then from my experience the Owon SDS models should be in your short list.
There is a EEV member on here (aghp) who deals with Owon in Europe and would be more than willing to help with any questions you have about the Owon kit.

p.s. I am not affiliated with Owon in any way bar that I am a happy Owon SDS7012 owner.

[aghp]

Becouse Owon hk download is some times extremely slow and also it may break connection unexpectedly here is other source.
 
Downloadable zip include: OWON_Patch_1.8.0_Setup_V2.0  + Md5 check tool + Readme.txt
zip is around 81Mb  (directly from Owon it do not have Md5 check)

Here you find  link to downloadable.  (also of course it can find Owon HongKong side but sometimes it is very slow)
Update (SDS7102  FW V2.5.1.x) is now available.
It is for older and new versions.

Look carefully your serial number.

I have tested with couple of units and after update these what I have tested:
V 2.5.1.6

(dependent your model/version there may be 1 or 2 number after 2.5.1 (2.5.1.?.?)


New Download 2.5.1.x

-aghp

[EU1]

Can enybody tell me how the vertical position adjustment is implemented? Is it adjusts voltage bias on analog frontend before ADC input, or it just moves a signal trace?

[rf-loop]

Can enybody tell me how the vertical position adjustment is implemented? Is it adjusts voltage bias on analog frontend before ADC input, or it just moves a signal trace?

It is adjusted in analog front end before ADC

Input (analog front end)  principle is conventional and quite well designed.
Vertical shift is not designed in kindergarten just as digitized trace shift.

First there is some passive components (step attenuator) R,C,(L) + Fujitsu RF relays and AQY214 as AC/DC switch
then:

1. ADA4817  Low noise fast 1GHz FET amplifier
2. ADA4932   >500MHz differential driver  Input offset adj come here from AD706 to ADA4932 Also of course ADC Reference V is here.
3. LMH6518  Digitally controlled 900MHz variable gain amplifier. Primary differential out to ADC and auxiliary differential out to Triger mux
4. MXT2002  2x500M/1x1000M ADC  (ADC08D500  clone) 

[EU1]

rf-loop, thank you for dispelling my doubts.

[rf-loop]

Not very bad.
Measured with peak-peak using 1M memory and 1GSa samplerate with 50us/div.
Persistence infinite. Then stop. Zoom out so whole capture is on the screen. Then with cursors.
 (with this setting Owon capture is 20div lenght so whole capturing is easy to look after one step zoom out and so that it is littlebit comparable to Agilent paper. (not exactly but no big difference in this noise meaning. Of course other kind of setting give lot of better result but this is not AD, so...nearly worst case realism. But this I do not know how much Agilent paper have bias...  )

[saturation]

rf-loop: very impressed that you put together all those noise floors for sample scopes.  I've seen some of those data from the Agilent application guide so I confirm your data.

http://cp.literature.agilent.com/litweb/pdf/5989-3020EN.pdf

[alm]

But this I do not know how much Agilent paper have bias...  )

That's an important point. They won't flat-out lie, but they will optimize the settings/circumstances that make the competition look bad and them look good.

[EU1]

I've just looked at power supply board circuit and have noticed that there is no battery management section except a "fake" battery charging indicator which just turns the LED off when a voltage becomes higher than some constant value.

So it seems that a battery module itself has a charging circuit in addition to a standard protection module.
Has anybody disassembled a battery and know how it is implemented (can it be disassembled without damage at all)? I've ordered a scope with a battery, but it will be delivered to me at the end of this month, so it is too long to wait...

$60 seems to be a very nice price for 4x4000mAh Li-Pol elements with a charger and a balancing circuit, so wondering about using it as a plug-in  module for other devices.

[saturation]

Absolutely true, but that holds for all application notes coming from manufacturers, it is geared subtly to make their products shine over their competitors, such as Tek's own scope notes.

However, its easy to confirm those readings; any owner can measure their quiescent noise themselves; but getting a chart with all the data together is more elusive.  It also serves as a simple yardstick to determine if your DSO noise is a bit more than should be.

I just checked this morning and as expected because of the lower bandwidth, an unmodded 50 MHz Rigol has under half the noise of all V/div ranges, using p-p values, using Agilent's method of shorting the output channel with a 50 ohm terminator.

But this I do not know how much Agilent paper have bias...  )

That's an important point. They won't flat-out lie, but they will optimize the settings/circumstances that make the competition look bad and them look good.

[hugos31]

explain how to measure noise at rest?

[rf-loop]

explain how to measure noise at rest?

In comparation table there read Agilent 5989-3020EN

After then "saturation" have give this link:
http://cp.literature.agilent.com/litweb/pdf/5989-3020EN.pdf

Do it need now copypaste here what reads in this Agilent paper?

I can help: It is explained on the side 4.
But it is better to read whole paper first and try understand what there reads. Then agen side 4.

Idea is collect enough data and find there peak level.

If example set Owon to 1k memory, 50ns/div (1GSa/s) and look what see in display with different V/div settings it looks lot of better. (example around 1.4 - 1.6mV p-p looking when scope is running but if collect more data with 1M or 10M setting and then look whole data there is peaks 2.4mV.
Measurement can do with open input and / or with terminated input. If open input enviroment need be EMI free so that input do not collect outside noise.

Visually with scope running it looks even better becouse eye do small trick with fast noise peaks. (in analog oscilloscope phosphor do this "noise filtering")

So, stop scope and then take whole collected data to screen so that it is example inside 5 - 10 horizontal divs. Then it can clearly see how fat is trace.
Also it can analyze from stored data file.

[Ryl]

Hi guys,

I am very interested in this Owon SDS7102, because my analogic scope seems to have some problems recently...
I searched where to buy this Owon and, except buying from China on ebay at ~380€ (with battery), it seems that I can't find it anywhere else with its battery for less than 500€, which becomes quite expensive...
But buying from China does not make me very confident about warranty, shocks during transport,... And what about any duty (because it comes from China) ? Sorry my English if I don't express myself clearly.
Another problem when buying from China is that I don't know if it is the latest version of the scope, I heard that some bugs have been fixed recently.

So it would be great from you to answer my wonderings about buying from China. And if not, where (in the EU) could I buy this scope with its battery for less than 500€, latest version ?

Thanks a lot for your help,
Ryl

PS : I still wonder which one is the best between this Owon and the Rigol 1052E (which isn't expensive at all)... But I heard about the fan noise (I hate that) and I don't want to take the Rigol apart to change it.

[Spawn]

So it would be great from you to answer my wonderings about buying from China. And if not, where (in the EU) could I buy this scope with its battery for less than 500€, latest version ?

I think nowhere Ryl, if I may ask where are you from?
There is a little online store in the Netherlands, price without battery is 449 Euros + 75 Euros for the battery:
http://www.eleshop.nl/nieuwe-serie-owon-sds7102-p-480.html

[alm]

Don't forget about VAT and import duties. A large, high-value item is more likely to be picked up by customs than a small padded envelope. Expect ~€70 VAT + €0-€38 duty (don't know the tariff for DSOs by heart) + whatever the transport company wants to charge for taking your money (eg. brokerage fee).

aghp on this forum appears to offer reasonable prices (cheaper than the above 'eleshop.nl' price) and good support. You won't find many other vendors offering burn-in testing for free.

[Ryl]

Thanks for the tips, I'll look at those sellers.
When looking at ebay sellers, I forgot the duties il my calculations... That makes a difference.

Ryl

PS : I just updated my profile, I live in Belgium.

[marmad]

DSOs made in China are duty free in EU - the base TARIC code is 9030 20:

http://ec.europa.eu/taxation_customs/dds2/taric/measures.jsp?Lang=en&SimDate=20120311&Area=CN&Taric=9030&LangDescr=en

Edit: Of course, you would have to pay VAT on price + shipping.

[Spawn]

Alm, he is from Belgium and eleshop is even closer to him than me while I am in the Netherlands 
There is no big price difference if you ask me, I would rather go for a shop which is closer to me than one further away, the option with battery is only 13 Euro more and without battery same.

That’s nice to know marmad,  but is that for company’s? Because on some Dutch forums people got caught with an oscilloscope and had to pay VAT.

[marmad]

I'm talking about personal import - not commercial.  There are two different 'taxes' we are talking about:  duty (douanerechten in Nederlands) and VAT (omzetbelasting).  In principle, when you import from a non-EU-country, the following rules apply (based on the value):

0 to € 22 = No duty / No VAT
€ 22 tot € 150 = No duty / Yes VAT
€ 150 and above = Yes duty / Yes VAT

If the customs people don't look at your package at all - then, of course, you might not have to pay anything.  But if you must pay duty, the amount that you must pay is based on the TARIC code and tariff (which you can look up at the site which I linked in my previous post).  In this case, a DSO made in China has a 0% duty - so no extra import fee even though the value is more than € 150 - but you still ALWAYS have to pay VAT if the value is listed as more than € 22 (and/or customs check the package).

Edit: Also, the values listed above (and the amount on which VAT is applied) is the cost PLUS shipping - in order to avoid people getting around duty/VAT by claiming the value is € 1 - but the shipping cost is € 100.

[Spawn]

Thanks marmad nice explanation, yeah the VAT (BTW in Dutch) is 19 to 21% over here, I am not sure which applies to an oscilloscope.

[EU1]

4. MXT2002  2x500M/1x1000M ADC  (ADC08D500  clone)

Is there any documentation available? I've found only two links, both on Chinese and both have quite a bit useful information:
http://www.mxtronics.com/NewsInfo.aspx?titleID=301
http://www.spacechina.com/n25/n144/n206/n216/c190964/content.html

Also on the photo you posted here it seems that the ADC package is brown. Is it just a uncommon compound color or something else?