believe it!

[GEuser]

Q

[aghp]

Hi

June 22, 2012, 03:24:34 AM  I did try help you.

I give to you list of instructions and ask you answer after you have made these tests exactly.

Never get any answer from you for diagnosing this problem and then possible give more advice for continue.

But of course all can do also with diy "try-mistake-try" method. Sometimes is good luck and then ask "oh what happend"...

Also there is available illustrated instructions for disassemble and assemble this scope. (it is littlebit obsolete for newest HW but for its purpose it give enough information - also after some changes in construction. For more deep works it is obsolete and there is not public material for this.

Btw. yellow-green protective ground lead is normally so short that if you do not pull it out from mains plug or take out other end (pow supply PCB)  screw you can not well separate bacside of oscillosccope.  (if pull out from mains connector end, then check connector tightness).  It do not need high force (sometimes it is not very tight) so I'm "nearly sure" (and becouse in disassembly phase you did not know it), you propably have used some (small) force and it have pulled out from connector so that you did not notice it. (of course there is 1:10000 posibility that factory have left it out but it is extremely rare and nearly impossible becouse every scope go to QC and safety check. If mains protective ground is open it fails in test. But humans work all is possible.)

Example Owon oscilloscopes what I have serviced and/or sold I have never find open safety ground connector (and I do this  "safety" test for every oscilloscope).  Also after service this wire need always check carefully and tighten connectors if need. This is normal primary fundamental in every professional electric and electronic service workshop. Also it is good practice for test this kind of things if sell any equipment what is made in developing or underdeveloped or declining countries without tight quality control and standards.

Edit/Addendum:

As normal in serious workshops also I have HP + 2 trimble GPS (tribled for control = If one is different from the other two, it can be voted out)  reference and well adjusted Rb's (tripled) as "house standard" (GPS I use for control that my freq references are ok, this is becouse GPS short time accuracy is not good as all know)

I have not find yet any Owon SDS what is out of specifications reference oscillator. But no one know how these go after long time ageing. Some units are nearly specifications borderline error. (I have not followed long time so I do not know what is typical ageing direction and what amount)

Also I have not find any Owon what is out of specifications if look voltage levels accuracy (after self calibration).
I have checked sold (and stock) equipments with Tektronix CG5011 and or CG5010. (my cal generators do not have certified calibration valid today but all my indirect  tests show also that they both are in ok accuracy (without official ISO certificate))

[aghp]

Hi

June 22, 2012, 03:24:34 AM  I did try help you.

I give to you list of instructions and ask you answer after you have made these tests exactly.

Never get any answer from you for diagnosing this problem and then possible give more advice for continue.

But of course all can do also with diy "try-mistake-try" method. Sometimes is good luck and then ask "oh what happend"...

Also there is available illustrated instructions for disassemble and assemble this scope. (it is littlebit obsolete for newest HW but for its purpose it give enough information - also after some changes in construction. For more deep works it is obsolete and there is not public material for this.

Btw. yellow-green protective ground lead is normally so short that if you do not pull it out from mains plug or take out other end (pow supply PCB)  screw you can not well separate bacside of oscillosccope.  (if pull out from mains connector end, then check connector tightness).  It do not need high force (sometimes it is not very tight) so I'm "nearly sure" (and becouse in disassembly phase you did not know it), you propably have used some (small) force and it have pulled out from connector so that you did not notice it. (of course there is 1:10000 posibility that factory have left it out but it is extremely rare and nearly impossible becouse every scope go to QC and safety check. If mains protective ground is open it fails in test. But humans work all is possible.)

Example Owon oscilloscopes what I have serviced and/or sold I have never find open safety ground connector (and I do this  "safety" test for every oscilloscope).  Also after service this wire need always check carefully and tighten connectors if need. This is normal primary fundamental in every professional electric and electronic service workshop. Also it is good practice for test this kind of things if sell any equipment what is made in developing or underdeveloped or declining countries without tight quality control and standards.

Look fella , do you take me for a idiot!
1> you have a conflict of interest , you sell these , you make money from them , therefore you are biased and would like to keep sales up .
2> If you read , i mentioned that i was very careful in disassembly , take note! slow and methodological and watched and saw everything to the minute'st detail .
3> you tell me now ? how to pull it apart  , "After i do it" , give me a break and get back to the sales office with the calculator , i do not need your free help OR want , what good did it do absolutely nothing , chasing this , do that , do this ,  'I' found the poor pathetic drama , The Scope .

So there you go , all the excuses of being lucky or accident or divine right , but the Absolute main thing is , i found it   without your perfect roadmap , so the story and pictures stand by itself whether correct or not .

Bye.

Now I understand also why your communication with Owon fails.

[digsys]

And readers will understand you . I like to be understood! 

Give the guy a break mate. I bought the same DSO a few weeks ago AFTER carefully reading through ALL the threads.
The aghp user has been VERY helpful to MANY people, without ANY expectations !! Don't go mouthing off without doing
research or you'll quickly find yourself on the "idiot" list, We have a few here already. It's not a nice way to start.
Just about everything you buy now days will have some kind of "bug". Either fix it or put up with it, If you're lucky,
someone (possibly even the manufacturer will solve it). For the price we paid for the SDS7102, it's a bargain !!

[SeanB]

If it is alcohol and you use a little elbow grease it will work. If you have some really potent homebrew ( double distilled or better, and it burns with a blue or colourless flame) it will work as well.

[aghp]

I have seen many Owon SDS series oscilloscopes (made for European markets) inside and never seen like this.

Sometimes I have seen some residues and fingerprints but anything like this total waste station garbage.

Also I see some other signs what let me think this unit is some kind of junk. But why this unit is packaged and sent to some seller and finally to end user. This unit belongs to factory inside material recycle garbage.

Did you find any signs that this unit have been opened before you did it?
( before there was also some suspect that protective ground wire was perhaps not ok)

Also these front end RF shields soldering are strange. What I have seen before it do not match.
Then I can see (perhaps) there is some marking pen traces on the board. Never seen these in new factory fresh unit.
Strange is also in one picture, there can see RF shield can is bent in a lot of.

Are there different standards product lines in Owon for example domestic markets?

If I'm you I send these pictures and explanation to Owon (and not to some basic level "email answering workers") and tell that you do not accept this junk and also ask Owon also inspect  in factory how it is possible this unit have passed QC and  sent out from factory.
Ask Owon give free DHL to return this unit and send unit what meets normal factory quality standards.

This information need reach factory higher level peoples who are responsible about quality and who have real power for solve your case.

-aghp

[marmad]

I have seen many Owon SDS series oscilloscopes (made for European markets) inside and never seen like this.

Rf-loop - I think maybe you haven't been looking that closely. Here is a close-up pic from the inside of one of the very first SDS7102s ever manufactured; I have quite a few photos with fingerprints. I have to assume that it's a common occurance in Owon's manufacturing. Even so, I'm not necessarily worried about fingerprints in the solder mask - but it is rather troubling to see the fingerprints overlapping the BGA devices.

[marmad]

see that dimple there but its protruding up , it nearly looks like something ive seen during my looking abouts inside stuff that when a ic has cooked a thing like that sometimes develops? what you think , just a guess please if you would not mind .

That's just the pin 1 marker for the IC - nothing to worry about with that.

[T4P]

It costs about 80 bucks direct from china, seems like it isn't a cheap arse one.

[saturation]

Thats a lot of work, but great recovery effort!  Thanks for documenting.

[tlu]

Hi GEuser,

Nice tear down, even the battery....wow! I only wish it had better UI and firmware. Features are limited as well. Hopefully this can be hacked. Does anyone know the underlying OS? Is it linux-based or windows-based or neither? I'm in between picking up this scope or the Hantek as budget is the gating factor for me. GEuser, what is your impression of the scope in terms of functionality and signal fidelity?

I saw the video by marmad and the over all scope is physically beautiful and nice big display. However, the firmware seems lacking in features such as dual window is not even implemented and no fine adjustments pointed out by marmad. Well, since you have the scope on hand I would also like your opinion.

Thanks,
Tim

[Dread]

I love my 8202V   
Works very well and I have had no issues with it.  The Battery pack is a fantastic option, I have already used the scope on a remote location and it really was nice not having to look for a spare power plug when I was working in the field also during battery mode the scope is not grounded so that could come in handy. (Assuming you of course plugged it out  )

[muvideo]

Hello, thank you for the info, so the battery is simply two cells in series and two
wires to connectors? No other electronics inside, balancing the cells and
checking the temperature and voltages? If so it's not good.

tlu the software is Java , Java Eclipse it seems
http://www.eclipse.org/ and http://en.wikipedia.org/wiki/Java_Eclipse

I hope someone savvy with Java reads and owns a 7102 and figures out how to stop chan2 being displayed when one actually turns off chan2 (bottom left corner) it's stupid having it there all the time imo ...

Afaik eclipse is only a general purpose ide, and java enviroment needs a "normal" OS.
I remember somewhere that tinhead mentioned that owon doesnt use any OS, or
uses some proprietary/non standard one, is it also possible that they programmed
the thing "bare metal" ?

Fabio.

[Bored@Work]

Java Equinox is the other mentioned and i think they are class files? , cheers...

Equinox would mean they use the Eclipse rich client platform. Equinox provides an OSGi framework - a thingy to plumb together components. You hack and slash your application into so many small components and libraries you no longer understand what all this is about. Then you use a component framework to glue it all together again, full with enterprisy stuff and management and whatnot, and hope it all starts up, and all the components are finding together.

Now, I have seen OSGi used on an embedded system once. But it was running on top of an operating system, and was a prototype ported from a desktop system. Could it be that the Java stuff was for the PC part of the software, i.e. the firmware updater, not the firmware itself?

[PA0PBZ]

It certainly looks like OSGi:

Code: [Select]

#Product Runtime Configuration File

osgi.splashPath=platform:/base/plugins/com.owon.uppersoft.patch
eclipse.product=com.owon.uppersoft.patch.product
osgi.bundles=org.eclipse.equinox.common@2:start,org.eclipse.core.runtime@start,RXTXcomm,ch.ntb.usb,
com.owon.uppersoft.common,com.owon.uppersoft.patch,javax.servlet,org.eclipse.core.commands,
org.eclipse.core.contenttype,org.eclipse.core.jobs,org.eclipse.core.runtime.compatibility.auth,
org.eclipse.core.runtime.compatibility.registry,org.eclipse.equinox.app,org.eclipse.equinox.preferences,
org.eclipse.equinox.registry,org.eclipse.jface,org.eclipse.osgi.services,org.eclipse.swt,org.eclipse.swt.win32.win32.x86,
org.eclipse.equinox.launcher,org.eclipse.equinox.launcher.win32.win32.x86
osgi.bundles.defaultStartLevel=4


[tlu]

If the firmware is implemented with Java, does this mean we can write custom firmware for this device?

Thanks,
Tim

[0xdeadbeef]

The firmware updater is a poor Eclipse rich client implementation, the scope's firmware isn't of course.

[tlu]

Help me understand where in the schematic did you applied your modification for the switch? Why did Owon design to have small current drain when battery not in use? Poor design or  intentional?

Tim

[digsys]

Here is a PS schemmy , i don't know how old/version it is , as noted previously there is a 4ma draw with the battery in and "off" , which surprises me as the scope needs no power as it has a button cell battery for the clock/time/date .. Reason i fitted a battery switch!

Very handy, I was about to pull mine apart to do similar. Do you have a slightly better res of the P/Supply? Did you get ALL the schematics?

.. where in the schematic did you applied your modification for the switch? Why did Owon design to have small current drain when battery not in use?
Poor design or  intentional? 

Looking at the schematic, if SOCBAT is connected directly to the battery, then the leakage is due to the battery powering the feedback circuit
located next to it. In which case, the charge circuit is a basic trickle charger ONLY. Not a "nice" method, but unless the current is set too high, reasonable
enough. Definitely something that could be "fixed".

EDIT: Posted this 2 secs after your post GEuser

[digsys]

As far as reading schematics go or understanding them i'm at my limit when it comes to ic's , but just following the b+ around it looks like it is the ic's that consume the current as it seems they need to be active to sense a AC/mains in , but hopefully someone more knowledgeable might take a look .

It is QUITE a common "problem" with switch-modes ONLY IF you have backup-power tied directly to the Output. In these cases, rather than waste power / efficiency / regulation by adding a 2nd series, say shottky diode, on the output, you put up with the leakage.
The circuit doesn't care, there's no AC mains to control. It can be designed "properly", but sometimes they don't care.

[digsys]

Do you mean actual picture of ps or the pic of schemmy ?, i can make a better one ...
Thanks for looking too digsys , i just assumed there would be a "fix" for it .

LOL, cross posted again :-)
Of the schematic. I am a bit confused as to what the AC Trigger cct does. J3? bottom left. Timebase? AC fail early warning sense?
Probably not important.

[digsys]

Service manual(basic 3.7mb with pictures and ps schemmy) and it is a earlier version as there is a connector on the video board that is there now in manual but not as now , i hope from memory at least as its been back together for a week or so .. 

Thanks a lot for the link, but my NOD A/V has flagged it as "on a list of potentially hacked links". Do you know it to be safe?

[digsys]

... that U3 is a led thing coupler yes? , there is a ma or 2 straight away? yes....

Yes, it's the DC regulation feedback. The entire op-amp circuits feeding it are also "always on".

See that manual , has better picture , and J3 , turns on led on front? i dunno , its a bit hard for me as ic's would be a weak point as i can not see any thermionic glowing going on

It's not important for this exercise. What you've provided has been very helpful. I'll do a google and look for another pdf source.
NOD definitely does NOT want me to d/load from that site :-)  Best I listen to it .. will update once I get further.

[muvideo]

From a first sight to the PSU schematic, seem that R11+U1 should sink almost 5mA, and more
than 2mA trough R14-R27, and remains U4, probably somewhere around 1mA.
That is the feedback circuitry from the flyback, I see no need to keep it powered while running on battery,
let alone when unpowered. If I didnt made any mistakes, and if the pcb permits, a possible
fix could be to power U4 and U1 from a second rectifier connected to T1 pin 10 instead of D4
that is always powered. Remains R14-R27, probably R14 could be disconnected from ground trough
a small mosfet (2n7002 for example) with the gate connected to U4 power, the same can be done
more cleanly with a pfet that disconnects R27-R28 from battery when the psu is off.

When my unit will be a little older I will try to mod it, it's VERY annoying to find the
battery flat after few weeks, and if we let it unpowered for few monthes we risk also to
damage the battery.

Fabio.

[aghp]

Hello, thank you for the info, so the battery is simply two cells in series and two
wires to connectors? No other electronics inside, balancing the cells and
checking the temperature and voltages? If so it's not good.

Fabio.

There is normal Lithium double cell's controller (afaik including balancing of course, hangzhou wanma is not whoever manufacturer)  circuit inside battery module.
(published picture do not show it, but sure it is "hidden" there)

Also you know it shut off outputs after cells are under safety level. In this state it can only charge.

In Finland I have one fully disassembled battery. (It was manufacturing fail, so I use it for study.) After I'm back in Finland I can send picture to you if you are still interest.

In China I do not have any disassembled battery.

Btw.. I have thinked EEVblog is blocked inside China but surprice... today I get it open but nearly unusable becouse veeery slow..