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

[TomC]

I meant ch1 ch2 on a usb key.

With the type set to Wave, as far as I know, you can only save one channel at a time or math. Once saved, however, you can display up to 8 saved waveforms simultaneously.

With the type set to Image, you automatically save whatever is on the screen, this includes both channels & math.

[TomC]

can someone please export two specific csv's from an Owon?

one when Owon ch1 enabled, no signal connected, AC counpled, timebase set to 500us/DIV, 10Mpoint, 1GS/s and the first volt/div with no bw reduction, so i think 5mV/DIV. And then second one with same settings but ch1 set to gnd.

I don't know of a way to export CSV files from the Owon. The attachments are binary files (.bin renamed to .hex) with the scope setup as you specified and the corresponding images so you can see what the waveforms looked like. I assumed that by no signal you meant nothing connected to the BNC. Hope that helps.

[TomC]

Just wondering, how did it pass the EMI test?

mlhstock, 160mVpp is in the normal range for scopes prior to the June production with modified PSU & Adapter boards. So provided you did the test using the setup guidelines suggested in recent posts, your scope's performance in this respect is similar to what other of us have been experiencing. On my scope, before I added some ferrites, the GND noise level was in the range of 145mVpp.

However, as I understand it, you were promised a scope from the June production. If I was in your shoes, I would try to convince the dealer to stand by their promise. I would state the facts without getting angry, and elevate the complaint to higher management if necessary. As a last resort, I would complain directly to Owon, explain the circumstances, and try to get at least new components to get my scope up to date.

[lemon]

can someone please export two specific csv's from an Owon?

one when Owon ch1 enabled, no signal connected, AC counpled, timebase set to 500us/DIV, 10Mpoint, 1GS/s and the first volt/div with no bw reduction, so i think 5mV/DIV. And then second one with same settings but ch1 set to gnd.

I don't know of a way to export CSV files from the Owon. The attachments are binary files (.bin renamed to .hex) with the scope setup as you specified and the corresponding images so you can see what the waveforms looked like. I assumed that by no signal you meant nothing connected to the BNC. Hope that helps.

TomC, he asked the first scale of Volts (2mV/div or 5mV/div). For what I remember, the SDS limited automatically the BW at these scales. Set the menu "Probe Set" to 10X and repeat the measurement.
There are many convertors "bin to csv", so there is no any problem with the bin files.

[rf-loop]

There are many convertors "bin to csv", so there is no any problem with the bin files.

I'm out from work and can not do it now but with this computer here was old Owon PC soft .11.

With Owon PC software you can convert bin file to .txt, .xls and  .csv.
If there is twi channel in use then there is Ch1 and Ch2 selection. If convert both it go to same file
something like this. (this is not from example image how to use PC soft)
In example image, there is 1M memory Ch1 and it produce around 13M .csv
(it was only Owon  .bin  file in this computer what I find)

(from Owon PC soft example files becouse it have two channel together)
First some information bytes
sample no,Ch1,Ch2
1,-600.00,3440.00
2,-600.00,3360.00
3,-600.00,3440.00
4,-600.00,3360.00
5,-600.00,3440.00
6,-600.00,3360.00
7,-600.00,3440.00
8,-400.00,3360.00
9,-600.00,3440.00
10,-400.00,3360.00
...

In PC soft, (of course first open stored .bin file from PC or USB memory  and then... )  first open View,  select data table, select sequence, Ch1 and/or Ch2 and then Save as...
Select file type and save. (10M bin to .csv  take some time... and result is over 100M if one channel)

[TomC]

There are many convertors "bin to csv", so there is no any problem with the bin files.

I'm out from work and can not do it now but with this computer here was old Owon PC soft .11.

With Owon PC software you can convert bin file to .txt, .xls and  .csv.
If there is twi channel in use then there is Ch1 and Ch2 selection. If convert both it go to same file
something like this. (this is not from example image how to use PC soft)
In example image, there is 1M memory Ch1 and it produce around 13M .csv
(it was only Owon  .bin  file in this computer what I find)

(from Owon PC soft example files becouse it have two channel together)
First some information bytes
sample no,Ch1,Ch2
1,-600.00,3440.00
2,-600.00,3360.00
3,-600.00,3440.00
4,-600.00,3360.00
5,-600.00,3440.00
6,-600.00,3360.00
7,-600.00,3440.00
8,-400.00,3360.00
9,-600.00,3440.00
10,-400.00,3360.00
...

In PC soft, (of course first open stored .bin file from PC or USB memory  and then...  first open View,  select data table, select sequence, Ch1 and/or Ch2 and then Save as...
Select file type and save. (10M bin to .csv  take some time... and result is over 100M if one channel)

Thanks rf-loop, now I know how to convert the .bin  files to .csv for tinhead.

[TomC]

can someone please export two specific csv's from an Owon?

one when Owon ch1 enabled, no signal connected, AC counpled, timebase set to 500us/DIV, 10Mpoint, 1GS/s and the first volt/div with no bw reduction, so i think 5mV/DIV. And then second one with same settings but ch1 set to gnd.

Thanks to rf-loop's post I was able to convert to .csv. Here are the files renamed to .txt.

[TomC]

TomC, he asked the first scale of Volts (2mV/div or 5mV/div). For what I remember, the SDS limited automatically the BW at these scales. Set the menu "Probe Set" to 10X and repeat the measurement.
There are many convertors "bin to csv", so there is no any problem with the bin files.

lemon, the probe menu was set to X10, that's why on the image it shows 50mV, but in reality the scope is internally set to 5mV/Div. With the help of rf-loop's post I was able to convert the .bin files to .csv and post them already converted for tinhead. Probably he had already found a way to convert them himself, but just in case I posted them too.

[mlhstock]

Just wondering, how did it pass the EMI test?

mlhstock, 160mVpp is in the normal range for scopes prior to the June production with modified PSU & Adapter boards. So provided you did the test using the setup guidelines suggested in recent posts, your scope's performance in this respect is similar to what other of us have been experiencing. On my scope, before I added some ferrites, the GND noise level was in the range of 145mVpp.

However, as I understand it, you were promised a scope from the June production. If I was in your shoes, I would try to convince the dealer to stand by their promise. I would state the facts without getting angry, and elevate the complaint to higher management if necessary. As a last resort, I would complain directly to Owon, explain the circumstances, and try to get at least new components to get my scope up to date.

Thanks, TomC. Yes, the dealer made a proposal that they will send me "a low-noise board" (I assume it's PSU) and I accepted the proposal. They asked me to replace the board myself and won't void my 3 year warranty.

[J4e8a16n]

I bought mine from a dealer on E-Bay (SMTZONE) that shipped the unit directly from Hong Kong.  Mine is from the new June batch and is very good.

I bought one recently  on E-Bay (SMTZONE) with serial SDS7102 1312 517

Is this a new batch?

As I am a newbe I dont know what to think.  Where is the explaination of the spring test?

What kind of capacitor is the 1000pF SDM: ceramic,  metal, etc.?


See attached the noise test as described in msg #1332

[lemon]

Your oscilloscope was made of 12th week of 2013 (at the end of March).

You measured the square pulse test (1KHz) not the ground noise.
Please look the same post as before at the attachment photo.
Fix the cable like this and connect both the tip and long ground cable (clip) to the same place (ground).
Follow again the procedure and capture the peak of noise.

[TomC]

I bought mine from a dealer on E-Bay (SMTZONE) that shipped the unit directly from Hong Kong.  Mine is from the new June batch and is very good.

I bought one recently  on E-Bay (SMTZONE) with serial SDS7102 1312 517

Is this a new batch?

As I am a newbe I dont know what to think.  Where is the explaination of the spring test?

What kind of capacitor is the 1000pF SDM: ceramic,  metal, etc.?


See attached the noise test as described in msg #1332

As far as I know the first 2 digits of the s/n, in this case 13, is the year (2013 in this case). The next 2 digits, in this case 12, is the week of the year. So your scope was built during the 12th week of 2013. Not quite the June batch, but scopes built during this period have been reported by other members to have lower GND noise than earlier batches. Member dgmoore78@yahoo.com's scope is 1319, so it was built during the 19th week of 2013, which is not quite June, but it's very close. We don't know exactly when Owon started phasing in the PSU and Adapter board changes, judging by dgmoore78@yahoo.com test results, it probably was a little earlier than June.

On your noise test you have the probe connected as you would to perform the compensation adjustment, this doesn't give you a good idea of the GND noise. You need to connect both the probe and the long ground wire to the scope's probe compensation GND lug. You also need to make sure that the scope's bandwidth is not limited, the image you posted shows BW where the Volts/Div setting is displayed, this indicates that you had the 20MHz bandwidth limit turned on. The noise is a low level signal, so you need to set the scope to the lowest Volt/Div setting that doesn't automatically limit the bandwidth, this is 50mV/Div when you tell the scope that you are using a X10 probe. Finally, you have to set the probe's switch to X10, this is because the X1 setting changes the bandwidth of the probe to about 6MHz.  Post #1330 summarizes what you have to do, if you want more details see post #1066.

The package where you received the probes contains a small spring clip that can be used instead of the long ground wire. If you use this spring for your ground connection the GND noise issue should just about disappear. You can test this the same way as explained above, just use the spring clip instead of the long ground wire.

The 1000pF SMD capacitor is most likely a ceramic capacitor, I just received the shipment from Owon, so I'm going to take a look and see what's in there.

Good luck with your new scope, and post the test results again.

[lemon]

TomC, you just received the shipment of Owon...we 'll waiting for the tests! 

[TomC]

TomC, you just received the shipment of Owon...we 'll waiting for the tests! 

Here are some photographs of what came in the shipment, tests will come later. The small package contains 2 power button caps, maybe they are expecting an accidental breakage. It also contains about six extremely small SMD capacitors, I may need to get new glasses to tackle those! I only need to install one, but the other 5 may be good practice.

[J4e8a16n]

I bought mine from a dealer on E-Bay (SMTZONE) that shipped the unit directly from Hong Kong.  Mine is from the new June batch and is very good.

I bought one recently  on E-Bay (SMTZONE) with serial SDS7102 1312 517

Is this a new batch?

As I am a newbe I dont know what to think.  Where is the explaination of the spring test?

What kind of capacitor is the 1000pF SDM: ceramic,  metal, etc.?


See attached the noise test as described in msg #1332

As far as I know the first 2 digits of the s/n, in this case 13, is the year (2013 in this case). The next 2 digits, in this case 12, is the week of the year. So your scope was built during the 12th week of 2013. Not quite the June batch, but scopes built during this period have been reported by other members to have lower GND noise than earlier batches. Member dgmoore78@yahoo.com's scope is 1319, so it was built during the 19th week of 2013, which is not quite June, but it's very close.

Here is another ground test.

[TomC]

Here is another ground test.

The noise level on this image seems to be a little higher than average, but by no means as high as has been reported by a few others. It's possible that some of this noise is not originating from the Owon. To see if this is the case try performing the test away from computers, fluorescent lights, and other electronic equipment. Also, the Owon's TFT panel (screen) radiates noise that we don't usually consider for this test, so keep the probe's cable as far away from the TFT panel as possible when performing the test. See post #1330 for a picture on how to position the probe cable for consistent results.

[TomC]

The new PSU board and the modified Adapter board are in. In general, I'm disappointed with the performance of this upgrade. Without ferrites, the new boards barely approximate the results I previously obtained by just adding ferrites when the old PSU was installed. Combining ferrites with the new boards don't improve the situation in most respects, the only exception is when the probe's cable is positioned next to the TFT panel. In this case you can see a significant change in the noise level.

The following images illustrate the tests I performed. There are four images for each test, sample mode, peak detect mode, average mode, and peak detect mode with the probe's cable next to the TFT panel. The conditions for the 3 tests I performed are as follows:

Test 1 - Old PSU in combination with a modified Adapter Board and no ferrites installed anywhere.

Test 2 - New PSU in combination with a modified Adapter Board and no ferrites installed anywhere.

Test 3 - New PSU in combination with a modified Adapter Board and 3 ferrites installed as I showed in post #1333.

Because captured images don't often convey the dynamics of what is happening, I initially captured 5 consecutive images of the same type as each posted image. The images posted are the one's with the highest noise values. So keep this in mind realizing that the noise fluctuates lower than what is shown in these images.

[TomC]

For those interested in the Adapter board modification, here is one image illustrating the capacitor installed ( my wife's eyebrow tweezers came in handy to hold and position that little SMD capacitor ). The other image shows the version number of the Adapter board I modified.

[lemon]

Here is another ground test.

As TomC you said, this noise level is a little higher than average.
My opinion is that noise is high if you set the schema of probe cable as we told you. If you set the schema of probe cables "free" and straight, OK this is an average noise.

(sorry for my english...)

[rf-loop]

The new PSU board and the modified Adapter board are in. In general, I'm disappointed with the performance of this upgrade.

Please can you take pictures from new adapter board (whole board) bottom and top side.
Same for new PSU board.

This picture what you now show about adapter board..... 
I really think now that Owon want totally shoot down themselves.
I can not see on the adapter board any signs of Owon made needed modifications.
5.5V and TFT backlight SMPS circuits need redesign! There need only follow simplest rules for design low noise SMPS circuits. I have done lot of free work for Owon and send lot of documents how to do it. 
(there need redesign PSU 8.4V  and -7.6V,  Adapter board TFT backlight, 5.5V and also 3.3V.
Also there is some other small things but they are not so acute - Example TFT databus)

And I can see they have not understood anything. (in this partial picture what TomC show)

I'm so angry now that it is better I do not write more...

[lemon]

No rf-loop there is no any new adapter board.
They did only the psu board.
They suggest to TomC (probably, because they haven't any new redesign adapter board), to adds only the smd 1000pF (bypassing a specific capacitor). Absolutely, they need to modificate the adapter board.

I compared the new psu board (from TomC photos) with an older that upload somewhere at 60-66 pages at this forum. I devided the board to two parts, the left and the right one. The left is until to two optocouplers and include the Richtek 7731 PWM (smd), the right is at the rest.
As you can see there is no any modification at the left side. All the modifications was at the right side, they rerouted some paths, they applied more gnd plane and of course they used (as you very well suggest) a lot of decoupling capacitors (smd type). I measured 23 smd decoupling capacitors, almost. Additional they cut the connection of power switch (metal cage) with the gnd.

[J4e8a16n]

Here is another ground test.

As TomC you said, this noise level is a little higher than average.
My opinion is that noise is high if you set the schema of probe cable as we told you. If you set the schema of probe cables "free" and straight, OK this is an average noise.

(sorry for my english...)

The negative clamp and the positive on the ground.
All equipement shut down. (I dont have much!)
Loose cable away from the screen.

So if I put ferrite, the noise  should be lower than average?
;-)

JP

[lemon]

If you put ferrites like TomC does, your sample noise gnd falling to 60-70mV (very good for my opinion). Don't forget to put and to battery cable (if you had battery as option).

[lemon]

Just, I finished the study of TomC's captures and see the following:

1) the decoupling capacitor of 1000pF, decreasing the noise 5-10% almost. He had 143mV and falled to 120mV. Perhaps, Owon doesn't any ready for the new adapter boards and it suggests a smal impovement without a lot of mods.
2) they have done some works with psu board. Of course, they followed the rf-loop's suggestions and I think that it works!. If you see my post #1306 (ac without 2 ferrites inside, mod electrolytics_smd.png) with the related mods like Owon's, I had almost 68mV ground noise. If you see the TomC's post #1333 (Ferrites In sample mode.png) he had 56mV almost. If you see the TomC's results at post #1373 (Sample-new psu, mod adptr, no ferr.png), with the new psu board the noise is 74mV. All these results is unrelated from the initial noise level and provides same noise level with a small differences.
For me, the new psu board seems that has eliminate the noise that related from itself.

I understand that TomC has disappointed about this result, but he is at the right way. He is like running the half race. For me, must to wait for the next level of adapter improvement.  The ferrites now can't to improve the noise, except the case that the probe's cable is positioned next to the TFT panel.  I suggest to him, add a ferrite to battery ribon cable, also)

[J4e8a16n]

Hi,

Did you meant  Vp or Vk  volts?

Joined: my last noise test.  Moving the oscilloscope in the lab does not change the result.

JP

.