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

[chromesphere]

Do you think it would be worthwhile putting something on the screen to protect it?  I still have the original plastic on the screen, but its got air bubbles in it and its a bit distracting.  Where could you get something that would fit the screen?
Paul

[AndrejaKo]

That would mostly depend on how careful you are with the screen. In my experience, the screen is tough and has some sort of coating that masks scratches. I really have to bring out a flashlight and a magnifying glass to be able to find any and I'm really good at noticing  small details such as screen scratches.

[chromesphere]

Cool AndrejaKo, makes sense to me, thanks!

Edit: ah ha!  I took the protective plastic off last night and noticed this morning there is a, sort of shiny line across the top of the screen, basically looks like a there already is a screen protector on it that's not perfectly straight!  So the layer you pull off when you get it, is kind of like the backing layer you pull off of a mobile phone screen protector.  So yeah...it comes with a protector.
Paul

[yuyu11uu111]

hey guys, i got my scope finally    took only about 3 - 4 days in dhl
great seller
i did the deal outside ebay and got this price of about 405$

-- whoever wants to look for him, his name is smtzone on ebay --

he included a free bnc leads, and i got with the scope an original bag (lifesaver to store the scope since i don't have space on my desk at the moment and until i will clean a bit to have space, it's nice that it's not getting dust on the meanwhile) which is great, i'll show in the pics\video i will do when youll just tell me if do you want me to do and how

as i suggested, i think i'm going to use lm386m-1 as an oscillator or some similar circuit to have a base line and not use the build in square wave that the comes with the scope

do you have a suggestions for testing this puppy in a way that will show if the problems that were in the 7102 fixed in this revision and latest firmware? if so, please post them out here with details

thank you

[Donziboy2]

Does the Owon still have noise issues?

[rstoer]

Does the Owon still have noise issues?

I think the reason no one's answered you is that no one really knows. The only person who might (rf-loop) has been strangely silent about Owon lately.
I own an older version of this scope (same generation as marmad reviewed) and I like it quite a bit. I agree with just about everything he said in the review but some of the things that were deal-breakers for him, like screen refresh speed and basic PC software, didn't matter to me. This is a very good scope for the money and the display is a knockout. I hope they get the noise fixed and quit messing around with it. Good luck with your search.

[digsys]

...  I like it quite a bit. I agree with just about everything he said in the review but some of the things that were deal-breakers for him, like
screen refresh speed and basic PC software, didn't matter to me. This is a very good scope for the money and the display is a knockout

Agreed ! Plus the battery option is invaluable if you need it (You do have to fit a Battery on/off switch though, but it's easy).
Even though I've used LeCroys most my life, the several times I had to use the Owon, it has done the job I needed it for. If you get too
carried away with nit-picking every limitation of every scope, you'll never be happy. IF it truly was a piece of cr@p, you'd  hear about it from
a LOT more people, in a LOT more forums.

[yuyu11uu111]

hi guys, how can i test if i have the noise problem your talking about, can explain to me how to test it and having accurate results

thank you

[rf-loop]

Does the Owon still have noise issues?

I think the reason no one's answered you is that no one really knows. The only person who might (rf-loop) has been strangely silent about Owon lately.
I own an older version of this scope (same generation as marmad reviewed) and I like it quite a bit. I agree with just about everything he said in the review but some of the things that were deal-breakers for him, like screen refresh speed and basic PC software, didn't matter to me. This is a very good scope for the money and the display is a knockout. I hope they get the noise fixed and quit messing around with it. Good luck with your search.

Why I'm quiet?

Becouse I do not know.

Sidenote: Also I have been quite busy with some other urgent works and if not enough then also this new Siglent SDG1020 CH1 other issue and CH2 other isue (in some units) but perhaps more rare issue have been "hands full of work". (CH1 square wave jitter/glitch issue have  solved by Siglent but CH2 load and amplitude dependent parasitic oscillation in some units in some situations  have been hard detective work and still it is partially uncnown. It looks like  it is somehow related to  changed highest voltage band output amplifier in CH2 output stage. This Ti OPA965 looks  more critical for components and PCB parasitics than some other nearly similar amplifier what they also have used.

If I tell  they (Owon) have solved it and it is agen just as it have been before it is true but it is true only in these scopes what I have get directly from Owon. I get new lot middle of last month.
It was just time they make changes to HW and I do not know what time they have add these changes to mass production in factory.  Now if I tell it is solved and then someone buy from some seller. Then he may be disappointed and his finger show me: you have told lie.
I know only these units what I have in my hand.
I do not know who seller now have ok units and who have issue units and who may even have units before this issue.

Also I can not understand who really make this mistake in Owon. Why make lot of changes to product what is ok in this meaning.  These changes are so stupid that even entry level young hobbyist can not do so stupid things.  I have waited that Owon tell apologies and tell that sorry "our EE who make these changes did not have anough experience and knowledge for this kind of changes" just as in history Hantek tell after one quite bad situation. (solved long time ago and today it is not anymore in class "pssst... keep your mouth " Just fun history.) I hope Owon do same: I hope that they may well have to admit that errors occurred due to a lack of experience and competence. Perhaps the changes in an underestimation of the complexity. And it is not the first company, which underestimate the SMPS circuits degrees of difficulty.
Now they know.

I hope they give full support for customers who suffer this issue.  I hope also they inform distributors how to handle this case so that in end there is satisfied end users.

Also it is still good to remember that (even in these units what have this issue what have talked before) there is not noise issue in oscilloscope froint end. If there is clean signal in scope input BNC then Owon is really clean and perhaps one of best in this oscilloscope class.  

There is also published test pictures where can see this issue and what it is after it have modified.

Long time ago I have send recommendations to Owon how they need change/modify circuits and then also recommendations for change some critical layouts on PCB.

What I know is that last time these units what I get from Owon this problem was gone and it looks agen like before this issue birth.

[TomC]

Does the Owon still have noise issues?

What I know is that last time these units what I get from Owon this problem was gone and it looks agen like before this issue birth.

On April 4 I left the following message at Owon's support:

"I bought my SDS71021246320 from Saelig here in the USA on January 17, 2013. Although I'm generally happy with the performance of my unit, this is one of the units that has the "GND noise issue". This is the issue extensively discussed in the EEVblog and ForumUp forums on the internet that involves excessive EMI radiation from the oscilloscope primarily originating from the SMPS circuits. In most applications this is not very bothersome. However, when full bandwidth is required while proving small signals (less than .5V), obtaining a good reading is very difficult unless the application allows use of the spring ground clip instead of the 6.5" ground lead. To alleviate the problem I have been using a 3" ground lead when possible. It is my understanding, that Owon has resolved this problem since around mid March, and is now shipping units that no longer have this problem. While this is great news for new customers, I would like to know what kind of help is or will be in place to fix units like my own."

I have left messages at Owon's support before and got a quick response. However, to this date, Owon hasn't responded to the above note.

I sent and almost identical e-mail to my dealer and got the following response the same day:

"Thank you for your recent purchase of the SDS7102V scope.  At this time, I do not have any information regarding a resolution of this noise issue, either with new products or concerning a remedy for existing scopes.  However, I will take up the matter with my contact at the Owon factory, and will respond to your question as quickly as I can.  I thank you in advance for your patience."

I haven't heard anything else from my dealer since then. Apparently his Owon contact hasn't responded, or as I fear, is ignoring him the same way I'm starting to suspect Owon is ignoring me and the many other customers that are being inconvenienced by this noise problem.

[TomC]

hi guys, how can i test if i have the noise problem your talking about, can explain to me how to test it and having accurate results

thank you

I don't know how familiar you are with your new scope so I'm going to give you extremely detailed instructions:

1) Take all probes and LAN or USB cables off of the scope and do a self calibration (Utility, Adjust, Self Calibration). Wait until it's done before doing anything else.

2) Preferably the scope should be away from other noise sources such as fluorescent lights, computers, switching power supplies, etc.

3) Connect a probe to the CH1 BNC and make sure it is properly compensated (see page 13 of the manual). Make sure the probe switch is set to x10.

4) Connect both the probe and the 6.5" ground wire to the ground lug of the Probe Comp terminals.

5) Set up the scope as follows:

CH1:

Coupling = AC
Inverted = Off
Probe: Attenu = X10, MeasCurr = No
Limit = Full Band
Volts/Div = 50.0mV
Vert Pos = 0.00div

Horizontal:

Horiz = Main
Horiz Pos = 0.00ns
Sec/Div = 500µs

Trigger:

Type = Single
TrigMode=  Edge
Source = CH1
Coupling = AC
Slope = /
Mode&Hold = Auto, Holdoff = 100ns
Level = 0.00mV

Acquire:

Mode = Peak Detect, or, Average
Length = 10M

6) The following is what I get on my scope, which has the noise problem, If you get a much thinner line you probably don't have the noise problem. You may want to post the images from your scope for others to see.

[yuyu11uu111]

hi guys, how can i test if i have the noise problem your talking about, can explain to me how to test it and having accurate results

thank you

I don't know how familiar you are with your new scope so I'm going to give you extremely detailed instructions:

1) Take all probes and LAN or USB cables off of the scope and do a self calibration (Utility, Adjust, Self Calibration). Wait until it's done before doing anything else.

2) Preferably the scope should be away from other noise sources such as fluorescent lights, computers, switching power supplies, etc.

3) Connect a probe to the CH1 BNC and make sure it is properly compensated (see page 13 of the manual). Make sure the probe switch is set to x10.

4) Connect both the probe and the 6.5" ground wire to the ground lug of the Probe Comp terminals.

5) Set up the scope as follows:

CH1:

Coupling = AC
Inverted = Off
Probe: Attenu = X10, MeasCurr = No
Limit = Full Band
Volts/Div = 50.0mV
Vert Pos = 0.00div

Horizontal:

Horiz = Main
Horiz Pos = 0.00ns
Sec/Div = 500µs

Trigger:

Type = Single
TrigMode=  Edge
Source = CH1
Coupling = AC
Slope = /
Mode&Hold = Auto, Holdoff = 100ns
Level = 0.00mV

Acquire:

Mode = Peak Detect, or, Average
Length = 10M

6) The following is what I get on my scope, which has the noise problem, If you get a much thinner line you probably don't have the noise problem. You may want to post the images from your scope for others to see.

Thank you very much, your explanation was accurate and very easy to understand even that i am very new to this scope (or any scope at all )

my scope have the noise problem also, mine get about 86mv in Vp and 29.6mv in Vk, but what i saw is that my scope is on about 2Mhz on the right lower corner and yours shows 470
as i understand it is because you used X1 and i used X10

also, i would love to know about how to test other problems like this if you can post a step by step like you did with the noise issue

thank's again

[Armageddon]

Hello.

I have a SDS8102V and, today I made the "test of noise" using the description of "TomC".

With a 200MHz probe (P6200) I get:
  -Peak:       Vp=24mV, Vk=9.2mV
  -Average:  Vp = 14mV, Vk = 7.8mV

With a 100MHz probe (T5100):
  -Peak:       Vp=19mV, Vk=8.5mV
  -Average:  Vp=12mV, Vk=6.5mV

I suppose that I don´t have the noise problem. What do you think?

Without probes I have measured a level noise of ~1 mV (BW = 20MHz) [x1] and ~2 mV (Full Band) [x1] with or without 50 ohm load.

I hope that these data be useful. 

Best regards.

[electroguy]

You guys have nothing to worry about!
using the same instructions by TomC, my 50mV/div setting is full of noise, and the 100mV/div setting shows that it's about 800mV p-p

sds71021219xx
firmware: 2.7.0

[Hydrawerk]

Oh, and once I wanted to buy this Owon scope... Anyway, is this problem even at the 200MHz version SDS8202??

[rstoer]

You guys have nothing to worry about!
using the same instructions by TomC, my 50mV/div setting is full of noise, and the 100mV/div setting shows that it's about 800mV p-p

Wow! Ladies and Gentlemen, I think we have a winner!

[yuyu11uu111]

You guys have nothing to worry about!
using the same instructions by TomC, my 50mV/div setting is full of noise, and the 100mV/div setting shows that it's about 800mV p-p

Wow! Ladies and Gentlemen, I think we have a winner!

lol 

can someone prepare some step by step ultimate guide to fix the noise all by our own (owon haha)

[rstoer]

As a point of reference, here are some shots of the noise on an SDS7102 with a build date of 2011, 27th week (old hardware and well before the noise issue surfaced). Probe at x1, with the long ground, is attached to the scope's ground point in the first three shots.
Shot #1 Shows noise level of 4.8 mV P-P. Note: 2mV per division automatically limits the bandwidth to 20MHz.
Shot #2 Shows noise level of 11mV P-P at the 5mV per division setting and full bandwidth.
Shot #3 Shows noise level of 4.4mV P-P at the 5mV per division, but with the bandwidth again limited to 20 MHz.
Shot #4 Shows the noise level with the probe held about a foot (30cm) in front of the scope. This measurement was taken with the scope in full bandwidth mode.

TomC's noise, while nearly twice mine, is probably not considered a problem. Electroguy definitely has an issue. It would be interesting to know the build dates of those units, and to get a few more points of reference.

The sharp-eyed among you will notice that my scope is actually a Aktakom. This is just a rebranded OWEN SDS7102. My serial number even reads: SDS71021127xxx

rf-loop's fix for the new models actually appears to reduce the noise to a point slightly below my version. Let's hope OWON implements his fix and then leaves the damn thing alone!

[Hydrawerk]

It is better to save the images in png format.

[rstoer]

It is better to save the images in png format.

Yes, I noticed that myself. I've updated the post accordingly.
Thanks.

[rf-loop]

Oh, and once I wanted to buy this Owon scope... Anyway, is this problem even at the 200MHz version SDS8202??

This whole terrible issue is in some manufacture lots.

Owon make some modification for main PSU (there is 2 SMPS) and adapter board what have also SMPS circuits.

Some schoolboy "EE" propbably do this work becouse of course this kind of small changes are easy.. only move some components and small changes in layout and then some components away what looks like do nothing... ... oh yes.. simple woirk and then becouse it is so simple directly order new PCB's for factory product line.

Yes, if look with signal generator etc.. all looks ok.  So, go on...

But in test lab... they do not as usually some peoples do... connect probe GND to somewhere and center to somewhere..   professional peoples have  mesurement practices  and  probe  with GND longwire is only for some  "blinking led" measurments.

Also I do not this if can avoid. Only for slow high level signals and so on in some service situation where only fast need look like "are there anybody home". And no problem with this common mode noise. 

Also there was no any reason to measure GND. Why I measure and watch just GND with oscilloscope. Is it fun, or just becouse  bored and nothing better to do..

But then, some really may use oscilloscope probe with long GND wire  for low level signals or fast signals.

If there is noise, first thing is take this short GND spring. 

Oh well... then connect probe longwire inductor as GND    to scope GND together with probe tip... and  voila...screenfull of noise...  what hell is going on - nearly drop from my seat.

After then start investigations that what hell is going on and why...screen is full of noise.
If connect clean signal to input BNC all is ok and more than ok... it is very good ok, also if use normally used short GND there is no problem at all.


 There is common mode high frequancy noise what is just converted to differential mode with this probing.

Now we know. Now also Owon know.

Later after I have time I will show some test pictures what ahave made using with one original "noisy GND" issue oscilloscope from factory and then just with exactly same tests using  factory new unit after this issue is repaired by Owon.

[hmlittle59]

Hello All,
My first Post.
I wanted to buy a O'scope soon and the Parallax Forum.com pointed me to this Site for Test Equipment feed back.  I had read in the Nuts & Volts magazine about the SDS5032E Scope.  They mentioned the SDS7102.  That was about 2 mths ago.  I've read most of the reviews about it and its noise problems.  I did email Owon and got a quick response about them working the problem and how to avoid it about a month ago.  I'm still waiting to see something on this forum about the problem being  99 - 100% fixed before I buy.    This Scope is in my price range that I want to spend.  I'm working with Parallax.com Micro-controller (BS2 MC & my own OEM's).  Some day soon I may move up to the Spin MC from Parallax, but not much more for now so this Scope should be more then enough.  But, I don't want to buy....I will NOT buy...a known problem.  I just read the latest feedback and will be waiting for more.   If the fix's works, how can I be assured that I get the latest/newest units off the assembly line. 

I'll be holding on to my dollars til I read here that its fixed.

Thanks to all who have given feedback(s) about the problems.

waiting.........

[electroguy]

TomC's noise, while nearly twice mine, is probably not considered a problem. Electroguy definitely has an issue. It would be interesting to know the build dates of those units, and to get a few more points of reference.

sds71021219xx
2012 week 19
firmware: 2.7.0

[Donziboy2]

Maybe this has been answered before but how badly does this affect normal signals you are checking on the scope?
Does it make small 100-200mVpp signals unreadable, or just butt ugly?
Is it noticeable with say 3.3V logic?
There is no perfect scope, I just want to know how crappy it is, to tell if it will interfere with what I may be doing.

[Hydrawerk]

I would not buy any Owon today, but if yes, try the scope at the shop, if it is OK. Do not buy over internet. It seems that Rigol DS1000, Siglent or Hantek hardly ever have such problems with noise.