Five more days in this beach with clear water!
Please for comparison reasons, repeat the test of noise ground as decribed at post #1330, page 89 and give us the Vp-p value and the capture.
More about:
The "Mainboard" also have a DC/DC connected to ~5.54V it generate noise that goes to the analog power of the input stage. This DC/DC supply power to the entire DAC.
Below the shielding metal sheets of the input stage there is a 5V LDO, connected to ~5.54V (i.e Vdo <0.54). And if Owon did not put any filters (F.Bead) in the input of the analog power for the DAC, less to the input of the analog power for the input stage. This LDO is able to reject only some frequencies <1MHz. Similar for the 7905.
Yes, please for comparison reasons, repeat the test of noise ground as decribed at post #1330, page 89 and give us the Vp-p value and the capture.
More:
- To correct variations between channel 1 and 2 in some oscilloscopes Owon add extra resistors there where Owon think.
- The 5V regulator thermally affects more the channel 1, since it is closer, this explains its greater DC drift.
Now I do not think Owon would like to save money, rather it seems that, did not even know how to make the oscilloscope.
Well done Owon... This is not an oscilloscope, is shit.
Carrington, I agree that the SDS7102 is not a perfect oscilloscope, that's probably the reason this thread is quickly approaching page 100. In regard to your comment about the low drop linear regulator (LDO), I'm glad that Owon at least had the good sense to use linear rather than pollute the input stage with another PWM converter. Owon is fairly new in the Test Instruments arena, so I'm sure that there are quite a few tricks they haven't learned yet. However, many of us can't afford a scope from the high end manufacturers, and Owon's SDS7102 features/price ratio is very attractive. I, for one, don't regret buying the SDS7102, it doesn't fulfill all my wishes, but it reasonably fulfills my expectations for the price I paid. We all wish we could get better performance, so we continue to tinker with new ideas on how to improve the SDS7102 ourselves. This doesn't mean that we totally dislike our scopes, and most of the negative comments you may occasionally see are just venting.
Carrington, I agree that the SDS7102 is not a perfect oscilloscope, that's probably the reason this thread is quickly approaching page 100. In regard to your comment about the low drop linear regulator (LDO), I'm glad that Owon at least had the good sense to use linear rather than pollute the input stage with another PWM converter. Owon is fairly new in the Test Instruments arena, so I'm sure that there are quite a few tricks they haven't learned yet. However, many of us can't afford a scope from the high end manufacturers, and Owon's SDS7102 features/price ratio is very attractive. I, for one, don't regret buying the SDS7102, it doesn't fulfill all my wishes, but it reasonably fulfills my expectations for the price I paid. We all wish we could get better performance, so we continue to tinker with new ideas on how to improve the SDS7102 ourselves. This doesn't mean that we totally dislike our scopes, and most of the negative comments you may occasionally see are just venting.
C'mon though - I made the review and started this thread almost precisely two years ago - and Owon hasn't bothered to upgrade the firmware with even the simplest of features which I (and many others) felt were missing - and some of them would have been quite easy to add - so it doesn't seem to me as if Owon has learned anything in the last two years (at least in terms of supporting and satisfying their user base).
Wow marmad, the thread that you started hit a new milestone! 100 pages, Congratulations!
I'm also disappointed with the progress in the firmware side, more so with unresolved bugs than the lack of new features. Owon's behavior in my opinion is counterproductive, but is their choice to decide where they want to go in the future. The main point I've attempted to make, is that in spite of the shortcomings, we don't all consider our Owon scopes to be totally manure. I'm still enthusiastic about the many things that I can do with my Owon DSO that were simply not possible with my old Tek CROs. I know that you now own a 70MHz Rigol DSO with very nice features. In my case, I already owned two 60MHz Tek CROs, so I wanted to get at least 100-200MHz for a new DSO. The SDS7102 offered 100MHz and was usable to 200MHz for a price I could afford. So I still think I did fine for my needs. But I do agree that Owon could do better, at least in popularity, if they would cater to user base needs and desires. There is nothing like word of mouth, in my opinion!
And after check how OWONs customer service work, do you think that they will apply the warranty?
I doubt.
Well I have no doubts. My scope's first fan became noisy after few months of use and was very quickly replaced.
Another problem was with recent firmwares, my scope would freeze from time to time when booting. Owon and my distributor couldn't figure out what was wrong and replaced the main board. It's been working fine since then.
Also it's strange that you, who doesn't care about Owon at all, is spending so much energy hating Owon and spreading the hate. Can't you just forget about us and move on to threads about good scopes?
Also in some cases, Owon, with all of its problems, is the only option. For example in my country cheapest Tektronix or LeCroy scopes cost couple of thousands of Euros. CROs start at around 700€ (and that's for 70 Mhz ones). "Local" Rigol distributor is in Italy, which makes them uncompetitive. This environment combined with salaries makes it worthwhile to take time to work out Owon's quirks.
Great work TomC, keep going in the same way!
Can you give me the Version of the newer psu board? I am looking at your photos that you had upload but there isn't seem nothing!
I am very curious about BBAAHHOO works. He took individual voltages from the psu board without needs the dc-dc adapter convertors that produce a lot of noise.
I've been trying to download BBAAHHOO's zip file from two different computers but all I get is html review of Owon sds... The log next two it says downloaded 2 times, so I don't know if there is a problem on my end or with the blog's download mechanism. Is any one else having this problem?