Author Topic: SDS7102 old stock serial identification (with noise issue)  (Read 9472 times)

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Offline luca1000Topic starter

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Re: SDS7102 old stock serial identification (with noise issue)
« Reply #25 on: May 13, 2013, 11:38:09 am »
Quote
Non of my scopes have noise problems and I measure often signals under 1 mV

can you please share the models of your scopes ?
« Last Edit: May 13, 2013, 11:40:45 am by luca1000 »
 

Offline rf-loop

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Re: SDS7102 old stock serial identification (with noise issue)
« Reply #26 on: May 13, 2013, 11:56:23 am »
If with a standard stock owon probe there is this problem, there is on the market a "particular probe" that can reduce this problem without use "a short ground" ?

It basic fundamental physic. If there is 15cm GND wire in Tektronix probe and 15cm GND wire in Owon pobe these both wires inductance is around equal.

If you compare example Agilent 100MHz (included in this one test image) oscilloscope noise Owon is far better. And THIS noise is inside agilent oscilloscope front end. You can not do there anything, it is made and designed so. Only accept it and live with it.  Owon you can... just care that signal coming to scope input BNC is clean.


These Owons what have this extra noise, it is mainly common mode and radiated noise. It depends now how you connect it to signal. There you can also do many things for reduce this noise. And mofre fun you just need these same methods if you work with higher frequencies and with signals what include fast changes. You need these methods also if oscilloscope do not have this problem.

Buying better probe... oh well. Perhaps you see then more noise if you still use same probing methods.

1. solution for noisy Owon is. REPAIR!
2. solution is try find methods to reduce signal pollution with this Owon spread spectrum radio transmitter.
3. waiting that you are sure Owon have  solved this whole case and what you buy is this improved version.
4. buy what ever, noisy or not if it meets your needs. (ther you can find tests with noisy unit and ok unit.

(and sidenote, if always or often need measure signals where level is around 1mV or less without any additional tools. If I do this I use some Bruel&Kjaer amplifier). Owon alone is just wrong tool. And many many others.

If you need this kind of scope, look also that low voltages are not fake.  (I mean this vertical zoom bullshit))
Oscilloscope what have 100nV/div is not cheap  and if its noise is really also good for this.  Perhaps then is much better to buy active probe what can do it and use normal scope. )

 
« Last Edit: May 13, 2013, 12:13:25 pm by rf-loop »
EV of course. Cars with smoke exhaust pipes - go to museum. In Finland quite all electric power is made using nuclear, wind, solar and water.

Wises must compel the mad barbarians to stop their crimes against humanity. Where have the (strong)wises gone?
 

Offline PA4TIM

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Re: SDS7102 old stock serial identification (with noise issue)
« Reply #27 on: May 13, 2013, 12:34:41 pm »
Quote
Non of my scopes have noise problems and I measure often signals under 1 mV

can you please share the models of your scopes ?
That has no use, unless you are willing to do you budget X 10 or buy a good analog scope. My DSO is a Hameg 350 MHz 2 Channel I  bought new about a year ago. So there are enough scopes with low noise but that are real instruments for real prices.

you are into audio, you now compare a multitech or a lenco amplifier
ect while you expect performances are for a Marantz or NAD (i'm not in to audio so pick your brand)
www.pa4tim.nl my collection measurement gear and experiments Also lots of info about network analyse
www.schneiderelectronicsrepair.nl  repair of test and calibration equipment
https://www.youtube.com/user/pa4tim my youtube channel
 

Offline luca1000Topic starter

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Re: SDS7102 old stock serial identification (with noise issue)
« Reply #28 on: May 13, 2013, 01:08:16 pm »
I suppose with a good old analogue scope (tek 24xx) I will get any performance problem ...

An old analogue scope have nothing to do about current chinese scope (like owon).

The problem is only the space ... I must think ....
« Last Edit: May 13, 2013, 01:17:35 pm by luca1000 »
 

Armageddon

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Re: SDS7102 old stock serial identification (with noise issue)
« Reply #29 on: May 13, 2013, 01:10:58 pm »
To "rf-loop" answer this pelase:  :-X

   a). What noise level is right for OWON?
   b). Will send Owon spare parts to all with this problem?
   c). What items (s/n) are affected? And do not tell me that OWON do not know.
 

Offline rf-loop

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Re: SDS7102 old stock serial identification (with noise issue)
« Reply #30 on: May 13, 2013, 03:46:46 pm »
To "rf-loop" answer this pelase:  :-X

   a). What noise level is right for OWON?
   b). Will send Owon spare parts to all with this problem?
   c). What items (s/n) are affected? And do not tell me that OWON do not know.


a)
Noise levels what are here in images I can accept.
here:
https://www.eevblog.com/forum/testgear/sds7102-old-stock-serial-identification-(with-noise-issue)/msg231565/#msg231565

Also here: tested "normal" and "noisy" SDS7102.


https://www.eevblog.com/forum/testgear/review-of-owon-sds7102/msg226398/#msg226398

This "normal" I can accept. This "noisy", this level I can not accept, but still also in many cases with it can live IF do not need measure very low level signals just with using probe long GND wire. It need also note that this "noisy" scope conducted and radiated RF noise may disturb some sensitive circuits what you are testing.

I can not write rules what noise is accepted and what is limit what can not accept. Also before this need
If someone want define the limit values there ??should first create a definition for it. Who determines what and how to measure.

b) I can not answer this. First people need ask seller. If seller do not want help and or solve this problem then customer need ask Owon. Only Owon make decisions how they handle individual situations.

c) I do not know. Also I have never told that Owon do not know. But, I do not know what Owon know and what not. Who want know he can send fax, call phone or send letter to Owon and ask Then, after get answer from Owon,  he know what Owon want tell. Also in this case you do not know what Owon know, you know only what Owon tell to you. If they give some public information it is as it is. If they give some personal answer it is only just it and nothing more.



-----------------
This is beginning to resemble the ring.
Nature of the problem is quite well aware of when you read and studied here in the forum what all peoples have tested and discussed over long time in many many threads about noise overall and about this case.

Universal noise level threshold value at which the device should reject or accept you're not going to get anywhere.
EV of course. Cars with smoke exhaust pipes - go to museum. In Finland quite all electric power is made using nuclear, wind, solar and water.

Wises must compel the mad barbarians to stop their crimes against humanity. Where have the (strong)wises gone?
 

Armageddon

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Re: SDS7102 old stock serial identification (with noise issue)
« Reply #31 on: May 13, 2013, 04:34:37 pm »
I thought so, ie we are going to anywhere. Or even more explicit: Probably OWON will do nothing for you if you have a machine with this problem, under warranty or not.  :-DD
 


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