Author Topic: 350Mhz Scope, 2020  (Read 4875 times)

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Offline andrea.longobardi85

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350Mhz Scope, 2020
« on: May 04, 2020, 05:33:31 am »
Hi All,

I am scouting for a professional oscilloscope with the following minimum characteristics:
- 4 channels
- 350Mhz bandwidth
- logic analyzer

I am try to find the right brand/model and then I will look for  deal on the web I guess.

I have boiled down to three brands (Rigol, Tek and Keysight) with the Keysight 4000X being my favorite, although the cheaper Rigol MSO5000 is tempting...

Any suggestions?
Anyone has experience buying second hand Keysight scope on Ebay?

As I said I need it for professional usage.

Thanks!

Andrea
 

Offline stafil

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Re: 350Mhz Scope, 2020
« Reply #1 on: May 04, 2020, 05:55:34 am »
Get this for $2000 (he will accept an offer for $2k) and hack it:

https://www.ebay.com/itm/Agilent-Keysight-DSOX3014T-100MHz-4Ch-5GS-s-Oscilloscope-with-N2890A-probes/383339365915


The think is, that even if you buy the MSO5k, if you really want a Keysight or Tek, you will end up buying one of them as well. If I was you however I would wait a bit. DSOX is a pretty old line and probably will get updated soon.
« Last Edit: May 04, 2020, 06:21:21 am by stafil »
 

Offline tautech

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Re: 350Mhz Scope, 2020
« Reply #2 on: May 04, 2020, 07:13:37 am »
Hi All,

I am scouting for a professional oscilloscope with the following minimum characteristics:
- 4 channels
- 350Mhz bandwidth
- logic analyzer

I am try to find the right brand/model and then I will look for  deal on the web I guess.

I have boiled down to three brands (Rigol, Tek and Keysight) with the Keysight 4000X being my favorite, although the cheaper Rigol MSO5000 is tempting...

Any suggestions?
Anyone has experience buying second hand Keysight scope on Ebay?

As I said I need it for professional usage.

Thanks!

Andrea
Welcome to the forum.

Just 3 brands ?  :-//
2 scopes from Siglent that are worthy of study as they fit your requirements:
SDS5034X or SDS2354X Plus are $3570 or less without options.
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Offline jemangedeslolos

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Re: 350Mhz Scope, 2020
« Reply #3 on: May 04, 2020, 07:39:50 am »
Why the SDS2354X+ when there is the SDS5034X for almost the same price ?
 

Offline tautech

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Re: 350Mhz Scope, 2020
« Reply #4 on: May 04, 2020, 08:05:12 am »
Why the SDS2354X+ when there is the SDS5034X for almost the same price ?
SDS5034X is just a bit dearer of the 2 ....both 350 MHz:
SDS2354X+ is $3k plus options but with basic decode free, shared vertical controls, 2 GSa/s and 200 Mpts mem.
SDS5034X is $3569 plus options but with basic decode free, individual vertical controls, 5 GSa/s and 250 Mpts mem and a SAPBus interface for active probes.
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Online nctnico

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Re: 350Mhz Scope, 2020
« Reply #5 on: May 04, 2020, 08:36:50 am »
Hi All,

I am scouting for a professional oscilloscope with the following minimum characteristics:
- 4 channels
- 350Mhz bandwidth
- logic analyzer

I am try to find the right brand/model and then I will look for  deal on the web I guess.

I have boiled down to three brands (Rigol, Tek and Keysight) with the Keysight 4000X being my favorite, although the cheaper Rigol MSO5000 is tempting...

Any suggestions?
Did you look at the R&S RTM3004?
https://www.eevblog.com/forum/testgear/rohde-schwarz-rtm3000-review/msg1604185/
There are small lies, big lies and then there is what is on the screen of your oscilloscope.
 

Offline Wuerstchenhund

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Re: 350Mhz Scope, 2020
« Reply #6 on: May 04, 2020, 09:57:17 am »
Hi All,

I am scouting for a professional oscilloscope with the following minimum characteristics:
- 4 channels
- 350Mhz bandwidth
- logic analyzer

I am try to find the right brand/model and then I will look for  deal on the web I guess.

These are pretty generic specs which leave a wide range of scopes..It would help if you could tell us what the scope is going to be used for. For example, how much memory do you need? Is 8bit resolution sufficient or do you need 10bit or 12bit? Any serial decode options? Power Analysis? Digital filters? Is FFT important? Statistics? What kind of probes do you need? And so on. There's a lot more to finding a scope that just channels and BW.

Also, what budget do you have? Because the price difference between the lower and upper end for 350MHz scopes as specified by you is some $15k.

Quote
I have boiled down to three brands (Rigol, Tek and Keysight) with the Keysight 4000X being my favorite, although the cheaper Rigol MSO5000 is tempting...

Frankly, the fact that you consider a $2800 Rigol as an alternative to a $11k Keysight tells me that you haven't spent enough time to consider what the scope will be used for and what your actual requirements are.

You are running a high risk to waste a lot of money for a scope which may or may not be the best choice for your use case.

I'm also not sure I would recommend Tektronix, which today is pretty much the bottom of the barrel when it comes to big brands, and unless you're really looking for a slow and excessively priced scope with poor support I would recommend to look elsewhere.

Brands you may want to include however are Siglent (especially the SDS5034X which is $3600 and which offers a wide range of functionality), Teledyne LeCroy (they have a new 12bit mid-range scope WaveSurfer 4000HD which offers 12bit resolution, the 350Mhz variant is around $14k) or Rohde & Schwarz (the RTM3004 for example).

Quote
Anyone has experience buying second hand Keysight scope on Ebay?

Yes, quite a lot actually. Mostly positive, and if you buy a 2nd hand Keysight instrument then you can buy new warranty (called 'repair agreements') from Keysight as long as the instrument is still within the support period.

You can do the same for LeCroy and Rohde & Schwarz, too.
« Last Edit: May 04, 2020, 10:05:03 am by Wuerstchenhund »
 
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Offline andrea.longobardi85

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Re: 350Mhz Scope, 2020
« Reply #7 on: May 05, 2020, 07:44:33 pm »
Hi all,

Thank you so much for your inputs. Here more details on what i am looking for:
1) 4 channel
3) 350Mhz at least + probes with same or higher BW
4) digital decoding (I2C, UART, SPI CAN)
5) FFT ( I do like the dedicated RF channel of the Teks...)
6) 10 inch screen will be nice
7) LAN interface
8) 2 channels waveform generator
9) affordable compatible current probe

I have a Siglent sds1102 but not really happy with the speed and user interface, I guess the new 5000 series is much better...

 

Offline tautech

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Re: 350Mhz Scope, 2020
« Reply #8 on: May 05, 2020, 08:01:54 pm »
I have a Siglent sds1102 but not really happy with the speed and user interface, I guess the new 5000 series is much better...
SDS1102..... all of those older variants came from a distant decade.  ;)
Even the SDS1102X while being much more capable has been surpassed by the X-E models and by lightyears further by 5kX and 2kX+ models.

While inbuilt AWG/FG's are convenient and save bench space their output performance sucks in amplitude and for a few $100 you can get a proper 2ch AWG with decent output drive that can interface directly with the scope for stuff like Bode plots.
Eg. The single channel 50 MHz FG option for 2kX+ is $219 and a 2ch 30 MHz SDG1032X is $319.
I know which I'd prefer.  ;)
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Offline Wuerstchenhund

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Re: 350Mhz Scope, 2020
« Reply #9 on: May 06, 2020, 06:19:31 am »
Hi all,

Thank you so much for your inputs. Here more details on what i am looking for:
1) 4 channel
3) 350Mhz at least + probes with same or higher BW
4) digital decoding (I2C, UART, SPI CAN)
5) FFT ( I do like the dedicated RF channel of the Teks...)
6) 10 inch screen will be nice
7) LAN interface

Well, that's not really a lot more information and still leaves you with scopes from some $2k to > $15'000.

FFT is standard on pretty much every scope, but there are differences in resolution capability (oh, and that Tek dedicated RF channel is nothing more than a separate input for scope FFT) and processing speed.

Decoding for I2C, UART, SPI and CAN has also been more or less standard (either included or as option) except for a few really low cost scopes.

Probes, well, pretty much all scopes come with only passive probes which don't go over 600MHz, and which in reality are only good for signals up to 250MHz-300Mhz. Anything better will be at extra cost, and very likely be expensive.

You still haven't told us the important bit, which is what you want to do with the scope and what your budget is.

Quote
8) 2 channels waveform generator

As Tautech wrote, get a standalone one. It's a lot more cost effective and you get a lot more for your money than with any of the buildings-in AWGs.

Quote
9) affordable compatible current probe

As a general rule, current probes from scope manufacturers are not cheap, and what is áffordable'to you depends on how much you want to spend (which goes back to the question about your budget).

Quote
I have a Siglent sds1102 but not really happy with the speed and user interface, I guess the new 5000 series is much better...

SDS1102 what (There's a whole decade of various SDS1102xxx scope models)? CL? CML? CNL? CFL?

In any case, as Tautech said if it's one of the older scopes then a lot has happened since then, and the current Siglent scopes have improved a lot since then.
« Last Edit: May 06, 2020, 06:21:38 am by Wuerstchenhund »
 

Offline EEVblog

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Re: 350Mhz Scope, 2020
« Reply #10 on: May 06, 2020, 07:08:21 am »
Anyone has experience buying second hand Keysight scope on Ebay?

The official Keysight ebay store is excellent. And oyu can often get extra software options thrown in for free if you ask.
https://saving.em.keysight.com/used-equipment/products/search/en?utm_source=eev&utm_medium=ban&utm_campaign=eevblogapr20&q=n99
 

Offline EEVblog

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Re: 350Mhz Scope, 2020
« Reply #11 on: May 06, 2020, 07:10:58 am »
Don't R&S have a bundle deal on their RTM3000 scope at the moment?
The RTM3K-32M would suits your needs, really nice scopes, 10 bit ADC.
https://www.batronix.com/shop/oscilloscopes/Rohde-Schwarz-RTM3K-32M.html
« Last Edit: May 06, 2020, 07:14:22 am by EEVblog »
 

Online TurboTom

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Re: 350Mhz Scope, 2020
« Reply #12 on: May 06, 2020, 07:34:49 am »
When looking at this range, I would rather spend 900 Euro-Bucks more and get the "promotion package" for the full bore version: https://www.batronix.com/shop/oscilloscopes/Rohde-Schwarz-RTM3K-COM4.html
 
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Offline EEVblog

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Re: 350Mhz Scope, 2020
« Reply #13 on: May 06, 2020, 07:37:27 am »
When looking at this range, I would rather spend 900 Euro-Bucks more and get the "promotion package" for the full bore version: https://www.batronix.com/shop/oscilloscopes/Rohde-Schwarz-RTM3K-COM4.html

That's the one I was thinking of. Bargain for such a high spec scope.
 

Offline Gandalf_Sr

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Re: 350Mhz Scope, 2020
« Reply #14 on: May 06, 2020, 09:16:13 am »
Hi all,

Thank you so much for your inputs. Here more details on what i am looking for:
1) 4 channel
3) 350Mhz at least + probes with same or higher BW
4) digital decoding (I2C, UART, SPI CAN)
5) FFT ( I do like the dedicated RF channel of the Teks...)
6) 10 inch screen will be nice
7) LAN interface
8) 2 channels waveform generator
9) affordable compatible current probe

I have a Siglent sds1102 but not really happy with the speed and user interface, I guess the new 5000 series is much better...
The Rigol MSO5074 would look like a good fit for your needs.  They were including all the decode and AWG options for free and that made it great value but, at least in the US, that promotion seems to have ended. You can go up to 350 MHz by paying more ($3,000)  or there is the information here in this forum to hack the firmware up to MSO5354 standard (it's all the same hardware).

Rigol make an $867 RP1001C current probe but I use an old Tektronix A6302 current probe (0-20A, DC-50MHz) with an AM503 Current Probe Amplifier which I refurbished myself.  You simply feed a BNC output to the scope input (on the MS)5074 you will need a $20 50 \$\Omega\$ feed thru BNC terminator).  I got that setup for about $300 on eBay and was using it yesterday.
If at first you don't succeed, get a bigger hammer
 

Offline thinkfat

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Re: 350Mhz Scope, 2020
« Reply #15 on: May 06, 2020, 09:43:29 am »
A lot of scopes will fit. That's the problem with giving advice. When the requirements are too generic and not weighted, everybody will just suggest their personal favorites.
 
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Offline KE5FX

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Re: 350Mhz Scope, 2020
« Reply #16 on: May 06, 2020, 11:00:27 am »
 

Offline EEVblog

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Re: 350Mhz Scope, 2020
« Reply #17 on: May 06, 2020, 01:13:39 pm »
A lot of scopes will fit. That's the problem with giving advice. When the requirements are too generic and not weighted, everybody will just suggest their personal favorites.

Agreed. At least a ballpark price is needed. $3k? $5k? $7k? $10k?
 

Online nctnico

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Re: 350Mhz Scope, 2020
« Reply #18 on: May 06, 2020, 01:56:22 pm »
A lot of scopes will fit. That's the problem with giving advice. When the requirements are too generic and not weighted, everybody will just suggest their personal favorites.
That at least gives a list with candidates. The next step for the OP is do some research on the various models (read datasheets and reviews) and then get a few on loan to see which one fits best. In the end getting hands on experience is the best way to make a good decission.
There are small lies, big lies and then there is what is on the screen of your oscilloscope.
 
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Offline Wuerstchenhund

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Re: 350Mhz Scope, 2020
« Reply #19 on: May 06, 2020, 03:19:57 pm »
A lot of scopes will fit. That's the problem with giving advice. When the requirements are too generic and not weighted, everybody will just suggest their personal favorites.
That at least gives a list with candidates. The next step for the OP is do some research on the various models (read datasheets and reviews) and then get a few on loan to see which one fits best. In the end getting hands on experience is the best way to make a good decission.

I severely doubt that test-driving random scopes with no plan or basic thought spent on what is needed will be a good decision. If you even get the scopes, because if you don't have any idea what you really need or at least what it is used for and what the budget is then they are unlikely to just hand over scopes costing several grands.

Quite frankly, unless the OP comes up with more details then any effort is wasted.
 

Online nctnico

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Re: 350Mhz Scope, 2020
« Reply #20 on: May 06, 2020, 04:55:24 pm »
Well, the OP has stated professional use and he/she already has an oscilloscope. My guess would be that the OP is in a good position to recognize value (improvement) for money.
There are small lies, big lies and then there is what is on the screen of your oscilloscope.
 

Offline Wuerstchenhund

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Re: 350Mhz Scope, 2020
« Reply #21 on: May 06, 2020, 06:24:14 pm »
Well, the OP has stated professional use and he/she already has an oscilloscope. My guess would be that the OP is in a good position to recognize value (improvement) for money.

"Professional use" may well just mean that someone else pays for the scope.

And all we know is the OP has some "SDS1102", which can be everything from the long obsolete CL Series from 2008 or so to the current SDS1102X-E. The only thing we know for sure it's a bottom-of-the-barrel scope.

Frankly, where you see "a good position to recognize value (improvement) for money", I see someone who is about to waste a shitload of money on something without understanding the basics.

Unless of course, the OP knows and just doesn't say, but then what's the point of these postings with only rudimentary information content?

Doesn't matter anyways, as there clearly isn't much engagement by the OP.
 
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Offline Gandalf_Sr

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Re: 350Mhz Scope, 2020
« Reply #22 on: May 06, 2020, 07:16:29 pm »
Don't be so hard on the OP, he's made 2 posts now.  There was once a time (when Pontius was a Pilate) when you had only 2 posts.

If someone else is buying, I want one of these...
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Offline Wuerstchenhund

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Re: 350Mhz Scope, 2020
« Reply #23 on: May 06, 2020, 08:02:08 pm »
Don't be so hard on the OP, he's made 2 posts now.  There was once a time (when Pontius was a Pilate) when you had only 2 posts.

That is true, but it's not the number of posts which I find strange, but the lack of engagement with any of the replies. I just think it's atypical compared with what we normally see from people looking for advice. That's all.

Quote
If someone else is buying, I want one of these...

I'd rather take one of these  ;D

« Last Edit: May 06, 2020, 08:04:31 pm by Wuerstchenhund »
 

Offline andrea.longobardi85

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Re: 350Mhz Scope, 2020
« Reply #24 on: May 06, 2020, 08:02:21 pm »
Here we go the third post!
1) I have got an SDS1102CML, but I have used Teks MDO3000 during my employee life...
1) budget 4.5K. Although it depends, if worthwhile I can get a loan :)
2) usage...I do electronics consulting... so I need it for different things...
Never had the need to go above 350Mhz so far and it think it is unlikely to happen.
But as I said , with my work is hard to know what I am going to debug tomorrow...

I think the best approach for me would be to get the higher spec scope for the budget I have...
 

Offline Wuerstchenhund

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Re: 350Mhz Scope, 2020
« Reply #25 on: May 06, 2020, 08:16:01 pm »
Here we go the third post!

Great!  :)

Quote
1) I have got an SDS1102CML, but I have used Teks MDO3000 during my employee life...
1) budget 4.5K. Although it depends, if worthwhile I can get a loan :)
2) usage...I do electronics consulting... so I need it for different things...
Never had the need to go above 350Mhz so far and it think it is unlikely to happen.
But as I said , with my work is hard to know what I am going to debug tomorrow...

Well, that's something we can work with ;) Sounds what you're after is more like a general purpose scope rather than an analysis scope.

$4.5k sounds solid and should give you some options, although it will rule out many of the A-brand options.

WIth your budget, I'd probably consider the Siglent SDS5034X and maybe also the new SDS2304X+. I only know the SDS5000X but it's a really good scope with a lot of functionality you won't find anywhere else in that price class. It also has 50ohms/1M switchable inputs and an active probe interface (and I believe adapters for Tek and LeCroy probes are in the pipeline).

There's also the Rigol MSO5000 and MSO7000 which both should fit your budget as well, but both don't offer the same level of functionality you get in the Siglent scopes.

Another option could be a 2nd hand Keysight DSO-X3034T, which should be within your budget, too, even with the optional repair package. It's a good scope but the architecture is designed with a strong focus on update rates and comes with comparably small memory (4M vs >100M with the other scopes) and limited functionality.

I'm sure others may chime in with more options.

Lastly, I would not recommend to get a loan for anything more expensive, you're much better off just buying something that is within the budget and then get something else when you feel that it's no longer enough (and by then you'll know exactly what you need).
 
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Online nctnico

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Re: 350Mhz Scope, 2020
« Reply #26 on: May 06, 2020, 08:30:42 pm »
Not sure about the advice not getting a loan. If a piece of equipment generates revenue to cover the costs of a loan then it is not a bad investment. But it should be noted that test equipment devaluates faster than a car. Buying something cheap now and upgrading later may end up costing more compared to a loan. OTOH debt is debt and it causes a long term outgoing cash flow; the business should be able to support that.

To the OP: Regarding the Siglent: one thing to watch out for is that it uses a different memory management compared to the Tektronix you are used to; Siglent typically cuts the memory short to have just enough samples to fit the screen. This has to match your usage. For me this kind of memory management is a hard fail. All in all it still is a good idea to compare several scopes yourself. I think the R&S RTB2004 also fits the budget without needing a loan.

If you really need a lot of bandwidth then getting a used higher end oscilloscope is a cheap solution.
« Last Edit: May 06, 2020, 08:37:37 pm by nctnico »
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Offline tautech

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Re: 350Mhz Scope, 2020
« Reply #27 on: May 06, 2020, 09:15:30 pm »

To the OP: Regarding the Siglent: one thing to watch out for is that it uses a different memory management compared to the Tektronix you are used to; Siglent typically cuts the memory short to have just enough samples to fit the screen. This has to match your usage.

That is utter BS !

As andrea already uses an old Siglent DSO I'm quite sure he knows how Siglent memory depth management works and with later versions of their scopes having substantially more memory depth, 100x in the case of the SDS2000X Plus, it is not the issue that some make it out to be.

We've been over and over this.  ::)
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Online nctnico

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Re: 350Mhz Scope, 2020
« Reply #28 on: May 06, 2020, 09:25:14 pm »

To the OP: Regarding the Siglent: one thing to watch out for is that it uses a different memory management compared to the Tektronix you are used to; Siglent typically cuts the memory short to have just enough samples to fit the screen. This has to match your usage.

That is utter BS !
That is because you want to sell Siglent. Just be fair and see the downsides for a change. No shame in that.
Quote

We've been over and over this.  ::)
And it doesn't work the way I want an oscilloscope to work; the way the Siglent scopes work seriously hamper my productivity. And I'm not the only one who sees shortening the record length to fit the screen as a downside.
« Last Edit: May 06, 2020, 09:26:46 pm by nctnico »
There are small lies, big lies and then there is what is on the screen of your oscilloscope.
 

Offline Elasia

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Re: 350Mhz Scope, 2020
« Reply #29 on: May 06, 2020, 09:32:16 pm »
Best bang for the buck at the moment i'd say is the sds2000x plus line that just came out recently

Just got mine here not to long ago importing from batronix and it works fantastic

Agree about tek... tek has become a dinosaur to avoid.  Keysight or R&S if you want top notch but you will pay for it too


You can get a SDS2350X+ with the MSO options for  3089 euro before vat

But like nconico said.. watch out for the memory model and some of the screen drawing distortions with on screen menus etc.. other than those annoyances it does practically everything i'd ever need
 

Offline EEVblog

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Offline tautech

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Re: 350Mhz Scope, 2020
« Reply #31 on: May 07, 2020, 05:17:52 am »
1) budget 4.5K. Although it depends, if worthwhile I can get a loan :)

USD or euro?

How about a cheap older Keysight 6000 series:
https://saving.em.keysight.com/used-equipment/products/oscilloscopes-digital-waveform-analyzers/dso6034a-e174165392146/en
Used 3000 series:
https://www.ebay.com/itm/Keysight-Used-MSOX3034T-Oscilloscope-mixed-signal-4-16-channel-350MH-/193312457919?hash=item2d025204bf
Yeah well, the OP's stated requirements:

1) 4 channel
3) 350Mhz at least + probes with same or higher BW
4) digital decoding (I2C, UART, SPI CAN)
5) FFT ( I do like the dedicated RF channel of the Teks...)
6) 10 inch screen will be nice
7) LAN interface
8 ) 2 channels waveform generator
9) affordable compatible current probe

Tough ask I know however with a new SDS2354X Plus there's sufficient budget left for a cheaper current probe and a 2ch AWG with decent output.
Knowing the current probe specs required would be helpful.

You need get one of these in your hot little hands Dave to get a proper handle on what you get for the $.
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Offline EEVblog

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Re: 350Mhz Scope, 2020
« Reply #32 on: May 07, 2020, 05:43:03 am »
You need get one of these in your hot little hands Dave to get a proper handle on what you get for the $.

I have got one.
 

Offline tautech

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Re: 350Mhz Scope, 2020
« Reply #33 on: May 07, 2020, 05:45:39 am »
You need get one of these in your hot little hands Dave to get a proper handle on what you get for the $.

I have got one.
Oh, you've been very quiet about that.  :-X
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Re: 350Mhz Scope, 2020
« Reply #34 on: May 07, 2020, 06:12:02 am »
You need get one of these in your hot little hands Dave to get a proper handle on what you get for the $.
I have got one.
Oh, you've been very quiet about that.  :-X

Hardly. Have tweeted photos of it and it's shown in the latest Mailbag.
 
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Offline andrea.longobardi85

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Re: 350Mhz Scope, 2020
« Reply #35 on: May 07, 2020, 07:35:05 am »
Hi All,

Thanks for all your inputs! it is 4.5k Euro and this is the budget I have allocated just for the scope.
Concerning the current probe I would need something > 5Mhz as I do lot of DC/DC.

I am considering at the moment those two options:

1)R&S RTB2000
https://www.batronix.com/shop/oscilloscopes/Rohde-Schwarz-RTB2K-COM4.html

2) SDS5034x bundle:
https://www.batronix.com/shop/oscilloscopes/Siglent-SDS5034X.html

Although the RTM3K bundle is really tempting...but would need to gather more $$$
https://www.batronix.com/shop/oscilloscopes/Rohde-Schwarz-RTM3K-COM4.html

Thanks!
 

Offline tautech

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Re: 350Mhz Scope, 2020
« Reply #36 on: May 07, 2020, 07:46:05 am »
Hi All,

Thanks for all your inputs! it is 4.5k Euro and this is the budget I have allocated just for the scope.
Concerning the current probe I would need something > 5Mhz as I do lot of DC/DC.

I am considering at the moment those two options:

1)R&S RTB2000
https://www.batronix.com/shop/oscilloscopes/Rohde-Schwarz-RTB2K-COM4.html

2) SDS5034x bundle:
https://www.batronix.com/shop/oscilloscopes/Siglent-SDS5034X.html

Although the RTM3K bundle is really tempting...but would need to gather more $$$
https://www.batronix.com/shop/oscilloscopes/Rohde-Schwarz-RTM3K-COM4.html

Thanks!
Interesting are the R&S promos when the SDS5000X promo is not offered in EU.  :-//
https://siglentna.com/digital-oscilloscopes/sds5000x/

There are threads for these DSO's on the forum and Dave has done teardowns and shootouts for some too.

Amp/sensitivity range for the current probe ?
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Offline andrea.longobardi85

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Re: 350Mhz Scope, 2020
« Reply #37 on: May 07, 2020, 07:51:21 am »
10A/10mA will do!
 
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Offline Wuerstchenhund

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Re: 350Mhz Scope, 2020
« Reply #38 on: May 07, 2020, 08:24:33 am »
Not sure about the advice not getting a loan. If a piece of equipment generates revenue to cover the costs of a loan then it is not a bad investment. But it should be noted that test equipment devaluates faster than a car. Buying something cheap now and upgrading later may end up costing more compared to a loan. OTOH debt is debt and it causes a long term outgoing cash flow; the business should be able to support that.

You are right that test equipment depreciates pretty fast, but the worst depreciation is with test equipment from the big brands. It's as simple as that, unless it's some exceptionally specialist or rare piece of kit. Big brand scopes are really poor when it comes to depreciation, and funny enough the B-brands tend to lose a lot less over the years (at least what younger test equipment, i.e 5 years or so) is concerned. Not because they hold their value better but because they already start from a much lower price point when new. So based on the purchase price to resale factor alone, big brand scopes fare pretty bad. So there's that.

Considering this is for electronics consulting in (as it seems) a wide and flexible range of areas, it's unlikely to assume that any instrument bought today will satisfy all requirements which come up with the next 10 years, not only because the accelerated progress of technology. With this in mind, it's futile to buy excessively now just to hopefully be "on the safe side" later on. And even if the original assumption turned out to be correct, the feature will very likely have been bought at a premium compared with what it could cost later if it was acquired when it's actually required. So it makes sense to buy something which satisfies the current needs, and when the time comes the instrument no longer suffices then move to something new.

As to getting a loan, there are situations where it certainly can make sense to get a loan to buy better equipment, but frankly based on the requirement (a 350MHz scope for general purpose work) I can't see any justification for that. Getting a gold-plated solution with no need for it is nothing more than a waste of money.

Because of the end of the day, this thing has to amortize over set period (which also depends on the specific country;'s tax laws). Which for a more expensive scope means you either have to use a longer amortization period (if you can, but which also means you might have to stick with it longer than you want to), or you have to charge your customer more (or live with a lower profit).

Quote
To the OP: Regarding the Siglent: one thing to watch out for is that it uses a different memory management compared to the Tektronix you are used to; Siglent typically cuts the memory short to have just enough samples to fit the screen. This has to match your usage. For me this kind of memory management is a hard fail. All in all it still is a good idea to compare several scopes yourself.

The only fly in the ointment here is that most scopes work that way (and I think that others have tried to make you understand this in a long-winded discussion not too long ago). For the simple reason that people normally capture long sequences on a scope and then zoom *in* on the details, while you for some reason seem to insist on capturing short sequences and then zoom out(?) somehow?  :-//

This is true for the majority (all?) scopes out there, maybe aside from the Keysight DSO-X (InfiniVision) Series, which allow no manual memory management whatsoever.

Now as to what Tek does: the MDO3000, like other Tek scopes, have a function called Auto-Magnify, where on very short timebases the scope continues to use the full record length (or appears to, as in reality it doesn't use that short time base). In Auto-Magnify, when you reduce the timebase, the actual time base is also reduced but only until you reach a point where the scope can now achieve the full sample rate. Any further reduction in timebase will then not further reduce the actual time base, but instead the scope shows a zoomed-in screen while capturing at the unchanged timebase setting. Further reducing the timebase just zooms further into the signal.

That's it.

Also, Auto-Magnify doesn't work when zoom mode is enabled, for obvious reasons.

While this is an automatic mode, the *exact* same effect can be achieved with any other scope using the zoom function (turn the timebase up right until the sample rate reaches max, then zoom in).

Which is what most people do anyways.

Quote
I think the R&S RTB2004 also fits the budget without needing a loan.

The RTB is a very basic scope, and the real only thing it has going for it is the 10bit resolution. Aside from the basic functionality, it also lacks an active probe interface or even simple 1M/50ohms switchable inputs.

I can't see how such a basic instrument would fit the requirements.

Quote
If you really need a lot of bandwidth then getting a used higher end oscilloscope is a cheap solution.

As I understand the 350MHz BW is sufficient. But yes, if more BW (a lot more, i.e. >1GHz) is required, the 2nd hand market becomes a great option.
« Last Edit: May 07, 2020, 08:48:51 am by Wuerstchenhund »
 

Offline Wuerstchenhund

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Re: 350Mhz Scope, 2020
« Reply #39 on: May 07, 2020, 08:43:15 am »
Hi All,

Thanks for all your inputs! it is 4.5k Euro and this is the budget I have allocated just for the scope.
Concerning the current probe I would need something > 5Mhz as I do lot of DC/DC.

I am considering at the moment those two options:

1)R&S RTB2000
https://www.batronix.com/shop/oscilloscopes/Rohde-Schwarz-RTB2K-COM4.html

I wouldn't recommend the RTB2000. It's quite limited in functionality and memory, and lacks an active probe interface or even 1M/50ohms switchable inputs.

Quote
2) SDS5034x bundle:
https://www.batronix.com/shop/oscilloscopes/Siglent-SDS5034X.html

I believe this would be a good option for you. It's a very good scope which gives you a lot of functionality, you get active interfaces (adapters for Tek and LeCroy probes are in the pipeline), and you don't need to break the bank.

Quote
Although the RTM3K bundle is really tempting...but would need to gather more $$$
https://www.batronix.com/shop/oscilloscopes/Rohde-Schwarz-RTM3K-COM4.html

Like the RTB, the RTM has the 10bit resolution going for it, how useful this is for you at this stage is something only you can say. In any case, unlike the RTB2000 this one does have an active probe interface and 1M/50ohms switchable inputs.

If the higher BW is what you're after, there also seems to be an offer for the 1GHz SDS5104X:

https://www.batronix.com/shop/oscilloscopes/Siglent-SDS5104X.html

In any case, try to get some hands-on experience with these scopes. It's a lot of money to just spend blindly.
 

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Re: 350Mhz Scope, 2020
« Reply #40 on: May 07, 2020, 09:13:50 am »
Quote
To the OP: Regarding the Siglent: one thing to watch out for is that it uses a different memory management compared to the Tektronix you are used to; Siglent typically cuts the memory short to have just enough samples to fit the screen. This has to match your usage. For me this kind of memory management is a hard fail. All in all it still is a good idea to compare several scopes yourself.

The only fly in the ointment here is that most scopes work that way
Not most. It seems to be about 50/50. Don't try to twist the reality!
And zooming out after a capture is very useful. Trigger on a detail, check if the detail is right / wrong and then zoom out to check whether the rest of the signal is (still) as expected. This is a very efficient way to do design verification.
« Last Edit: May 07, 2020, 09:16:06 am by nctnico »
There are small lies, big lies and then there is what is on the screen of your oscilloscope.
 

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Re: 350Mhz Scope, 2020
« Reply #41 on: May 07, 2020, 09:24:54 am »

Concerning the current probe I would need something > 5Mhz as I do lot of DC/DC.

10A/10mA will do!
Ok, had a look around at a few and unless you spend a bit they all seem to fall flat on their face with poor frequency derating unless they have higher BW's.
I thought Testec from Batronix looked good for the price but nah.  :--
https://www.batronix.com/files/Testec/Manuals/TT-CC_Manual_EN.pdf

Here's Siglent's offerings FWIW:
https://www.siglenteu.com/wp-content/uploads/2017/11/Current_Probes_DataSheet.pdf

How much is too much for a good current probe ?
I've done a bit of 500 KHz DC-DC convertor work too and always got away with a Tek P6021 AC current probe and apart from only being an AC rated probe they still whip most of the current (excuse pun) offerings
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Offline Wuerstchenhund

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Re: 350Mhz Scope, 2020
« Reply #42 on: May 07, 2020, 09:50:35 am »
Quote
To the OP: Regarding the Siglent: one thing to watch out for is that it uses a different memory management compared to the Tektronix you are used to; Siglent typically cuts the memory short to have just enough samples to fit the screen. This has to match your usage. For me this kind of memory management is a hard fail. All in all it still is a good idea to compare several scopes yourself.

The only fly in the ointment here is that most scopes work that way

Not most. It seems to be about 50/50. Don't try to twist the reality!

OK then, please name some makes and models who do not.

Quote
Zooming out after a capture is very useful. Trigger on a detail, check if the detail is right / wrong and then zoom out to check whether the rest of the signal is (still) as expected. This is a very efficient way to do design verification.

Can you explain with what you mean by "trigger on detail"? Because the trigger doesn't care what the actual timebase setting is, so for a trigger to work it makes no difference if you're on a short or a long timebase.

And if you're interested in the complete signal then the logical process is to capture the whole sequence and then zoom *in* on the "detail" you're interested.

It's also what Auto-Magnify on a Tek MDO does: keep the scope on a longer time base and zoom in on the detail. Only difference is that on the MDO it's default behavior.
 

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Re: 350Mhz Scope, 2020
« Reply #43 on: May 07, 2020, 09:58:57 am »
And if you're interested in the complete signal then the logical process is to capture the whole sequence and then zoom *in* on the "detail" you're interested.
You are starting to sound like Tautech now. Trying to convince people a hammer is quicker than using a nail gun.

If you are a design engineer then you'd understand that least twiddling with knobs is better to get the job done. Bonus points if a piece of equipment does what you want without needing to care how it is setup exactly; it acquires the data you need. That is what this is all about. If an oscilloscope just captures the full record length you set then the zoom and time base settings don't matter much; you get the data you need. I want to concentrate on the problem at hand, not on the test equipment. Again, these are the little details that make life so much easier which don't make it into the datasheet.

Practical case: check data in an SPI frame. Time base & trigger point set so the data in the SPI frame is visible including timing of the edges. Once the timing is correct set the timebase to a lower time/div to inspect the rest of the signal. Be aware that taking one acquisition may several minutes in some cases. Or more if it is a rare bug. Getting a setting wrong means waiting that several minutes (or longer) again. Taking the oscilloscope's precise setup out of the equation just makes life easier especially if this measurement cycles needs to be repeated several times where it is easy to forget about the oscilloscope's setting. Very important if nobody is paying for the extra time spend on a problem.
« Last Edit: May 07, 2020, 10:21:00 am by nctnico »
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Offline Wuerstchenhund

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Re: 350Mhz Scope, 2020
« Reply #44 on: May 07, 2020, 10:24:05 am »
And if you're interested in the complete signal then the logical process is to capture the whole sequence and then zoom *in* on the "detail" you're interested.

If you are a design engineer then you'd understand that least twiddling with knobs is better to get the job done. Bonus points if a piece of equipment does what you want without needing to care how it is setup exactly; it acquires the data you need. That is what this is all about. If an oscilloscope just captures the full record length you set then the zoom and time base settings don't matter much; you get the data you need. I want to concentrate on the problem at hand, not the test equipment. Again, these are the little details that make life so much easier which don't make it into the datasheet.

Well, I spend my time with many other things than designing stuff these days, so I'm probably not an authority here, but I don't tend to just "twiddle knobs" without spending a thought on what I actually want to achieve. In fact, I always think about how the scope needs to be configured to show me the data I want first, and then go do it. I'm not the "let's poke in random stuf and see what we get out" type of guy.

Of course, that doesn't really matter for this discussion. But the other thing is that, in three decades of professionally specifying and procuring test equipment for various labs, not *once* did an engineer tell me that he wants a scope where he can "zoom out". Not. A. Single. Time.

Nor have there been any complains about the fact that none of our scopes do what you suggest.

Which tells me that your expectations of how scopes work aren't exactly mainstream ;)

Quote
Practical case: check data in an SPI frame. Time base & trigger point set so the data in the SPI frame is visible including timing of the edges. Once the timing is correct set the timebase to a lower time/div to inspect the rest of the signal.

Good example, but I still fail to see why this is relevant. I can easily trigger to any point in the SPI frame with serial triggering, which works completely independent on the timebase setting (because it follows the data). I set the trigger (plus any pre-trigger period if desired) and aquire the whole sequence, and then zoom in at the point of interest. Simples.

Quote
Remember that taking one acquisition may several minutes in some cases. Gettting a setting wrong means waiting that several minutes again. Taking the oscilloscope's precise setup out of the equation just makes life easier especially if this measurement cycles needs to be repeated several times where it is easy to forget about the oscilloscope's setting. Very important if nobody is paying for the extra time spend on a problem.

I'm sorry I still don't see it. You have to setup the trigger in any case, so there's that. The whole process is exactly the same, with the only difference that you want to start with a close-in and zoom out while I would start with a longer timebase and zoom in.

Let's just assume that we both use a scope which actually does what you want, there would be no time saving whatsoever between our processes, nor would there be a difference in the level of information. It. Just. Doesn't. Matter.

You're not "taking the oscilloscope out of the equation", besides that if you doing measurements without being aware of what your test instrument is setup to isn't exactly best practice.

Now there's then problem is that scopes don't tend to use more memory than what's necessary to fill the screen at the highest possible sample rate on short time bases.

BTW, I'm still waiting for the some examples of scopes (the roughly 50% of all scopes) that actually work as you claim.  ;)

:popcorn:
« Last Edit: May 07, 2020, 10:35:23 am by Wuerstchenhund »
 

Offline JPortici

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Re: 350Mhz Scope, 2020
« Reply #45 on: May 07, 2020, 10:27:58 am »
The RTB is a very basic scope, and the real only thing it has going for it is the 10bit resolution. Aside from the basic functionality, it also lacks an active probe interface or even simple 1M/50ohms switchable inputs.

I can't see how such a basic instrument would fit the requirements.

This. the RTB is really really REALLY basic and fairly slow to operate compared to the sds5000x

Also, most scopes i've had and used work the "siglent" way: older Tek TDS1000/2000/3000, Picoscope, Lecroy (both "REAL" ones with vxWorks and cheaper "firmware based"), ultimately the SDS-5000x
The "keysight" scopes i've used were keysight (duh) and rigol.
« Last Edit: May 07, 2020, 10:33:12 am by JPortici »
 
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Re: 350Mhz Scope, 2020
« Reply #46 on: May 07, 2020, 10:56:51 am »
I'm not going to debate this any further. I have made my position very clear on how to get work done efficiently. It is up to the reader to decide whether this applies to his/her use cases or not.
There are small lies, big lies and then there is what is on the screen of your oscilloscope.
 

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Re: 350Mhz Scope, 2020
« Reply #47 on: May 07, 2020, 11:12:35 am »
not again! tldr, why if there is a topic like this its treated like a loved wife? if he is really professional, he wouldnt ask in forum, and if he had to he wouldnt post such an open question. let him decide what he like to or not, there are abundant of infos in eevblog alone already. we can only provide infos its not our position to say blue is better than green :palm: if he later figure out its the wrong purchase, let him buy another it will be good for economy of some workers engineers out there...
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Re: 350Mhz Scope, 2020
« Reply #48 on: May 07, 2020, 11:19:29 am »
How much is too much for a good current probe ?
I've done a bit of 500 KHz DC-DC convertor work too and always got away with a Tek P6021 AC current probe and apart from only being an AC rated probe they still whip most of the current (excuse pun) offerings

I have a current probe I'm looking at selling for under US$250 and under $300 for a 2MHz unit.
 

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Re: 350Mhz Scope, 2020
« Reply #49 on: May 07, 2020, 11:39:40 am »
And zooming out after a capture is very useful. Trigger on a detail, check if the detail is right / wrong and then zoom out to check whether the rest of the signal is (still) as expected. This is a very efficient way to do design verification.

No scope I am aware of does this, they won't capture beyond the screen window. So if your timebase at the capture time is set to 1uS then you only capture 10us or so (can be slightly more) worth of data.
So you can't "zoom out" after capture as there is no data capture at longer timebase settings.
What you do is set a long time base and deep memory, trigger on some event, and then zoom in.
Well, this workflow (zooming out after a capture) is available on many DSOs. It is the standard (or at least configurable) on Tektronix, Rigol, GW Instek, R&S, the older Keysight scopes (DSO7000A / B series and derivatives), the original Siglent SDS2000 series and probably several others. However you have to realise that 'capture outside' the screen only works if there is memory left over after filling the screen. So it won't be the case at time/div settings where the maximum samplerate  is dropped. I have been using DSOs like this forever. I strongly recall being very annoyed by the Siglent SDS2000 not remembering this setting in the early firmware.

Edit: forgot to add MicSig.
« Last Edit: May 08, 2020, 09:24:16 am by nctnico »
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Re: 350Mhz Scope, 2020
« Reply #50 on: May 07, 2020, 11:45:25 am »
if only zooming is concerned, i can do that with my Rigol DS1054Z coupled with PC SW like my VisaDSO (if i find the built-in zoom feature is too limiting). i can save as documentations and later comparison with new revisioned circuit, do super long FFT, THD calculation etc to anything you like, the key is loooong memory and pretty good (usable) SW API to start with. if you cant program it, you can hire someone else to do it, isnt all pros work with Matlab nowadays? but i never consider it as pros method as i do this just for hobby. except the 100MHz BW (or attenuated 500MHz Nyquist frequency) limitation, if i need more BW with such a feature, i will buy higher end Rigol anytime. i havent deal so intimately with my used LeCroy SDA6000 yet if it has PC SW downloadable/transferable data but i can already see some of its limitation compared to my cheapy Rigol. another key for "pros" is.... download and study the DSO manual, today its in our fingertip! you can pinpoint your particular interest in there and/or compare with other scopes from their manuals, send the manufacturer a question if it has this or that. then later we can ask more specific, more delusive "brand-unbiased" features in forum with hope there is owner as member. we can save members from scratching each others faces too with unorganized omnidirectional post, ymmv.
« Last Edit: May 07, 2020, 12:02:12 pm by Mechatrommer »
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Offline Wuerstchenhund

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Re: 350Mhz Scope, 2020
« Reply #51 on: May 07, 2020, 12:48:19 pm »
I'm not going to debate this any further. I have made my position very clear on how to get work done efficiently. It is up to the reader to decide whether this applies to his/her use cases or not.

I can certainly accept that (although I really tried to understand your point), however I'm really disappointed that I now will never learn which of the some "50/50" of all scopes will allow "zooming out " on very short time bases  ;)
« Last Edit: May 07, 2020, 01:13:05 pm by Wuerstchenhund »
 

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Re: 350Mhz Scope, 2020
« Reply #52 on: May 07, 2020, 01:36:40 pm »
thats why you dont have to engage to troll like posts. if they dont have a working example, you can safely assume its just out of an air... thats how you survive around here, dont treat anything like a loved wife. and if they dont want to be the "best" like you, so be it.
It's extremely difficult to start life.. one features of nature.. physical laws are mathematical theory of great beauty... You may wonder Why? our knowledge shows that nature is so constructed. We simply have to accept it. One could describe the situation by saying that... (Paul Dirac)
 

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Re: 350Mhz Scope, 2020
« Reply #53 on: May 07, 2020, 02:06:56 pm »

To the OP: Regarding the Siglent: one thing to watch out for is that it uses a different memory management compared to the Tektronix you are used to; Siglent typically cuts the memory short to have just enough samples to fit the screen. This has to match your usage.

That is utter BS !
That is because you want to sell Siglent.
Not here, it's outside my assigned territory, whereas you can and do flog your stuff here:
For that you'll need a high speed differential probe (shameless plug: I sell a relatively low cost one)............
::)
Quote
Just be fair and see the downsides for a change. No shame in that.
There are no downsides other than in your mind, only power to the scope user in their ability to fully utilize the tools in the toolbox which appears you have some great difficulty adapting to.  :-//

We've been over and over this.  ::)
And it doesn't work the way I want an oscilloscope to work; the way the Siglent scopes work seriously hamper my productivity. And I'm not the only one who sees shortening the record length to fit the screen as a downside.
Oh poor didums,  :'( maybe one of these might suit you better:



Really, in this day and age how to use a DSO to best effect still escapes some.  ::)

How much is too much for a good current probe ?
I've done a bit of 500 KHz DC-DC convertor work too and always got away with a Tek P6021 AC current probe and apart from only being an AC rated probe they still whip most of the current (excuse pun) offerings

I have a current probe I'm looking at selling for under US$250 and under $300 for a 2MHz unit.
Yummy, some detailed specs on it would be nice....and current vs frequency derating curves.
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Online nctnico

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Re: 350Mhz Scope, 2020
« Reply #54 on: May 07, 2020, 02:27:24 pm »
I'm not going to debate this any further. I have made my position very clear on how to get work done efficiently. It is up to the reader to decide whether this applies to his/her use cases or not.

I can certainly accept that (although I really tried to understand your point), however I'm really disappointed that I now will never learn which of the some "50/50" of all scopes will allow "zooming out " on very short time bases  ;)
If you cared to read you can find a long list a few posts earlier.

@Tautech: your ad-hominem attack which lacks any technical substance is really mature. It just underlines that you get extremely pissed at anyone who (in your mind) attacks your livelyhood. Way to go!  :clap:
« Last Edit: May 07, 2020, 03:58:00 pm by nctnico »
There are small lies, big lies and then there is what is on the screen of your oscilloscope.
 
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Offline thinkfat

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Re: 350Mhz Scope, 2020
« Reply #55 on: May 07, 2020, 02:59:08 pm »
As far as I can say, all Rigol scopes capture the full sample memory when you ask them to. Of course the waveform update rate will take a hit. I find it convenient. But it didn't stop me from buying the SDS2104X+ instead of the MSO5074. I can achieve roughly the same behavior using the Zoom mode. It just takes a bit of additional setup because I need to first set a timebase that will capture the range I need to inspect and hit the Zoom button. Then, however, I can zoom in and out using the timebase control like on the Rigol.

However, I'd need to do a similar setup step on the Rigol scope, too, in choosing an appropriate memory depth (of course I can just set it to maximum, but then waveform update might be slower than necessary).
 

Offline Gandalf_Sr

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Re: 350Mhz Scope, 2020
« Reply #56 on: May 07, 2020, 03:05:17 pm »
 :popcorn:
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Offline 2N3055

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Re: 350Mhz Scope, 2020
« Reply #57 on: May 07, 2020, 04:41:55 pm »
On Keysight MSOX3000T, if you do single, or stop, it will sample full memory. Even on 1ns/div. Which will be some weird always different amount of time, depending on timebase...
That is why I insist than Nico's argument is wrong.
Yes it will try to capture full memory, (or exact amount of memory you set in digitizer mode, in newer firmware).
Problem is that I don't think and use scope in number of samples. I use it to capture certain time.
For instance I have 10 SPI packets that together are, let's say, 10 ms. I need to capture 10 ms.
Problem starts with fact that my full memory worth of capture means different time, based on timebase. So as I twiddle trough timebase, I need to keep an eye to at what sample rate I'm now so I can make mental calculation how much ms this will be "behind the screen"..
It will change all the time as I change timebase.
So basically Nico relies that his "full memory capture" will hopefully, maybe, with any luck, capture all of the stuff he needs...And will keep calculating in his head if that is going to happen or not.
If that is good workflow, I'm a bycicle...

But guess what, there is a very good way to deterministically do this. Easy too.
You set scope to capture whole time span with timebase (in this case 1ms/div, 10ms full screen if 10 divisions), set memory depth to make sure you have sample rate that is adequate for what you're doing (and verify both settings right there on the screen),capture whole thing in first try, and then zoom in and out of area of interest at will , for as long as you want to.. And it will do exactly as you commanded. Every time.

I did , once give right to Nico that on small scope screens, zoom mode takes up useful space.
I know that on Rigol DS1000Z you don't have to zoom, on stopped capture, you can use time base /hor pos to look around as a full screen zoom, in and out. So you can do whatever Nico does with signal, just captured in normal way, not relying "maybe it will get it". I can do same thing on MSOX3000T.

I don't know if you can manipulate dataset and displayed data on stopped capture in same manner on Siglent SDS2000X+.
I would like to know if that is possible. Could somebody try that please?
If it is, that makes Nico's argument completely invalid.
If you can't, that is a shame because that IS usefull.
BUT, since you have huuge screen10", zoom mode is not that problematic like on a 7" screen.
BUT, it would be nice if you could configure zoom mode size. I personally find that R&S does that nicely...
Regards,
 
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Offline tautech

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Re: 350Mhz Scope, 2020
« Reply #58 on: May 07, 2020, 04:50:39 pm »

 :popcorn:
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Online nctnico

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Re: 350Mhz Scope, 2020
« Reply #59 on: May 07, 2020, 05:00:32 pm »
So basically Nico relies that his "full memory capture" will hopefully, maybe, with any luck, capture all of the stuff he needs...And will keep calculating in his head if that is going to happen or not.
Here your reasoning goes wrong. A modern DSO has 10, 40, 80, 100, X Mpts worth  of memory. At 2 Gs/s 10Mpts is already 5ms worth of data. A time span of 5ms is more than enough to capture 5000 bits of SPI data clocked at 1MHz (which is low for typical SPI). So even when limited to the maximum samplerate you are very likely to capture all of the relevant data you need. There is no luck involved. Ofcourse there are situations where you may need to capture over a longer period of time but that doesn't mean 'my' way of working is useless to begin with.

Do realise that once you get below the point where the oscilloscope drops the samplerate, an oscilloscope will use the full memory length (typically configurable) for the acquisiton. There will be no data outside the screen in that case.

Quote
But guess what, there is a very good way to deterministically do this. Easy too.
You set scope to capture whole time span with timebase (in this case 1ms/div, 10ms full screen if 10 divisions), set memory depth to make sure you have sample rate that is adequate for what you're doing (and verify both settings right there on the screen),capture whole thing in first try, and then zoom in and out of area of interest at will , for as long as you want to.. And it will do exactly as you commanded. Every time.
That is way too much work for me. The DSO is there for me, not the other way around. The less twiddling knobs and the less clutter on the screen, the better. And increasing memory depths on DSOs keep pushing the need for using an exact time base setting further away. Actually I prefer not having to think about the time base setting. When I'm interested in a time aspect of a signal I'll zoom in/out to show certain parts of the signal and use the cursor readings to tell me. Ask yourself: Where is time/div even relevant in that?
« Last Edit: May 07, 2020, 05:32:51 pm by nctnico »
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Offline 2N3055

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Re: 350Mhz Scope, 2020
« Reply #60 on: May 07, 2020, 05:32:11 pm »
So basically Nico relies that his "full memory capture" will hopefully, maybe, with any luck, capture all of the stuff he needs...And will keep calculating in his head if that is going to happen or not.
Here your reasoning goes wrong. A modern DSO has 10, 40, 80, 100Mpts worth  of memory. At 2 Gs/s 10Mpts is already 5ms worth of data. A time span of 5ms is more than enough to capture 5000 bits of SPI data clocked at 1MHz (which is low for typical SPI). So even when limited to the maximum samplerate you are very likely to capture all of the relevant data you need. There is no luck involved. Ofcourse there are situations where you may need to capture over a longer period of time but that doesn't mean 'my' way of working is useless to begin with. And increasing memory depths on DSOs keep pushing that boundary further away.

Quote
But guess what, there is a very good way to deterministically do this. Easy too.
You set scope to capture whole time span with timebase (in this case 1ms/div, 10ms full screen if 10 divisions), set memory depth to make sure you have sample rate that is adequate for what you're doing (and verify both settings right there on the screen),capture whole thing in first try, and then zoom in and out of area of interest at will , for as long as you want to.. And it will do exactly as you commanded. Every time.
That is way too much work for me. The DSO is there for me, not the other way around. The less twiddling knobs and the less clutter on the screen, the better.
No I'm not wrong. And you were mentioning, for instance,  Keysight DSO7000A / B that don't have 100MS memory.
What you don't understand is that my way of working and your way of working  is exactly the same...
We both get same amount of data, except you do mental math (as you did in your response) to calculate sample size to  get amount of data you want, capture and then zoom out (with timebase knob), and I simply use timebase to capture whole event exactly, and use zoom in...
Neither is wrong, my way is a bit simpler (no mental math, all is already displayed on screen), and both get same results.

Only thing that is wrong is that you, quite theatrically if I may add, proclaim scopes useless if they don't conform to your way of use. And while I, on occasion, when looking at some fast edge, was able to zoom out with timebase, to see some parts of curve afterwards without need to reacquire, it is not something I rely on. The way I see it it is not a favorable feature, but more of your bad habit to capture data on wrong timebase, relying on scope to compensate for that. Sorry, that is my stance on the issue.

But I agree with you that:
- Most of the scopes use too much screen space for zoom mode. It should be tiny scroll bar just to get general idea of waveform and position in the buffer
- Preferably zoom window size should be user configurable (half, quarter screen, minimum, or even better infinite variable like R&S)
- Taking long capture at high sample rate is priceless. I have a deep mem scope because of that.
- When stopped, you should be able to "zoom in and out" with timebase and hor.pos. knob over full capture, like a sorts of "full screen zoom mode". That makes "zoom mode screen problems" go away completely, and is intuitive (same behaviour running and stopped).

Best regards,
 
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Online nctnico

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Re: 350Mhz Scope, 2020
« Reply #61 on: May 07, 2020, 05:34:49 pm »
I never proclaimed oscilloscopes which don't record beyond the screen if there is acquisition memory leftover are useless. I just noted that for me personally it is a hard fail. Sure you can get similar results using zoom mode but it also means more fiddling with knobs and settings things up just right. I like fire & forget better. You may call that a bad habit but I call needing to bother with the exact time/div setting a waste of my time and attention.
« Last Edit: May 07, 2020, 05:48:03 pm by nctnico »
There are small lies, big lies and then there is what is on the screen of your oscilloscope.
 
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Offline 2N3055

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Re: 350Mhz Scope, 2020
« Reply #62 on: May 07, 2020, 05:47:17 pm »
I never proclaimed oscilloscopes which don't record beyond the screen if there is acquisition memory leftover are useless. I just noted that for me personally it is a hard fail.
I will take this statement at face value, and will agree that you have all the right in the world to think so four you personally.
I appreciate you honest opinion. Thank you for taking the effort to clear that out for me.

All the best, Nico.
 
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Offline maginnovision

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Re: 350Mhz Scope, 2020
« Reply #63 on: May 07, 2020, 07:03:11 pm »
And zooming out after a capture is very useful. Trigger on a detail, check if the detail is right / wrong and then zoom out to check whether the rest of the signal is (still) as expected. This is a very efficient way to do design verification.

No scope I am aware of does this, they won't capture beyond the screen window. So if your timebase at the capture time is set to 1uS then you only capture 10us or so (can be slightly more) worth of data.
So you can't "zoom out" after capture as there is no data capture at longer timebase settings.
What you do is set a long time base and deep memory, trigger on some event, and then zoom in.

You literally have an R&S scope(any of their newer 'power of 10' scopes) which does it Dave. If you set the memory acq to auto it will capture screen(maybe extra), however you can specify the memory depth and regardless of your time/div window it will fill the memory. The result is a tight window focused on your trigger which you can pull back on to view surrounding events/data.
« Last Edit: May 07, 2020, 07:06:59 pm by maginnovision »
 

Offline stafil

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Re: 350Mhz Scope, 2020
« Reply #64 on: May 07, 2020, 07:54:38 pm »
I never proclaimed oscilloscopes which don't record beyond the screen if there is acquisition memory leftover are useless. I just noted that for me personally it is a hard fail. Sure you can get similar results using zoom mode but it also means more fiddling with knobs and settings things up just right. I like fire & forget better. You may call that a bad habit but I call needing to bother with the exact time/div setting a waste of my time and attention.

Sounds pretty useful feature.

Is there a name for it? How do you find out which ones do and which ones don’t.

 

Online nctnico

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Re: 350Mhz Scope, 2020
« Reply #65 on: May 07, 2020, 08:08:08 pm »
I never proclaimed oscilloscopes which don't record beyond the screen if there is acquisition memory leftover are useless. I just noted that for me personally it is a hard fail. Sure you can get similar results using zoom mode but it also means more fiddling with knobs and settings things up just right. I like fire & forget better. You may call that a bad habit but I call needing to bother with the exact time/div setting a waste of my time and attention.
Sounds pretty useful feature.

Is there a name for it? How do you find out which ones do and which ones don’t.
There isn't a specific name for it; you may be able to deduce it from the user manual but it is not clear cut. Hints may be automatic memory length versus being able to set a specific length but this doesn't guarantee that the full memory is used. The easiest way to test is to connect the probe to the calibrator output, set the memory depth to maximum, the trigger mode to normal and the level so the scope triggers to the calibrator signal, disconnect the calibrator signal so the triggering stops (do not go into stop mode!). Now turn the time/div knob to 200ns/div and see if you get more signal on the screen. If there is no extra signal on the screen then the oscilloscope does not record beyond the screen.
There are small lies, big lies and then there is what is on the screen of your oscilloscope.
 

Offline tautech

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Re: 350Mhz Scope, 2020
« Reply #66 on: May 07, 2020, 08:15:32 pm »
@Tautech: your ad-hominem attack which lacks any technical substance is really mature.
Oh that is a big word like  m-e-m-o-r-y  m-a-n-a-g-e-m-e-n-t  that you seem to not grasp why it's implemented.

Such are the advances in off the self componentry that entry and midrange DSO's are constructed with today to sustain another specification that you have many times claimed to loathe is WFPS which certainly matters to the A brands as they pursue it with custom ASIC's at great expense to endeavour to maintain high data throughput speeds although at the expense of memory depth the user has available to them. Choose your poison.

As you might know in some ASIC based DSO's the user often has little idea of the actual memory depth in use while the modern method of displaying memory depth available properly informs the user so they can make choices to best suit their needs.

As others have mentioned Zoom mode, where this really shines is to allow the full memory available for detailed long captures and still have almost seconds of data to pan through to inspect and all made immensely easier with a touch display.

All scopes have evolved and changed dramatically from the CRO's we used as youngsters and we've all needed to learn different methods of DSO usage and this still changes today as we know there are different design paths that groups of manufacturers each belong to. Each do very similar things albeit using different methods to obtain much the same result. Users need evolve also to fully take advantage of all the fruits the modern DSO offers.

However what mostly troubles me is when the OP says:
I have a Siglent sds1102 but not really happy with the speed and user interface, I guess the new 5000 series is much better...
You jump in with your standard anti Siglent memory management tirades as you commonly do and heavily pollute this thread just you have on numerous occasions.  :-//
Did you even consider the OP might be well aware of his old Siglents memory behaviour, somehow I doubt you did and just saw it as another good chance to have a good rant.  :rant:

It seems both reading posts and learning DSO memory management techniques are beyond you.  :-//
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Online Martin72

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Re: 350Mhz Scope, 2020
« Reply #67 on: May 07, 2020, 09:22:19 pm »
Siglent follows the way lecroy are handling the memory.
Rigol (surprise, surprise) does it to when the memory depth is setting to auto.
Apart from really special needs it´s normal behaviour.
So we should return to the first post of the thread starter.
Siglent got two mighty scope models in his pricerange, the sds5000x and the sds 2000x+.
Rigol too, but he want 10" screen therefore only the 7000 rigol range would be interesting.
For several reasons actually I won´t go for rigol models, siglent should be the choice when "pure" chinese scopes are interesting.
The Rode&Schwarz offering too less for the money, what RTB2000 series concerns.
Sure, it got 10" screen and higher screen resolution, but that is it at all.
Keysight and Tek I didn´t know really at all.


Offline 0xdeadbeef

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Re: 350Mhz Scope, 2020
« Reply #68 on: May 07, 2020, 09:48:15 pm »
The Rode&Schwarz offering too less for the money, what RTB2000 series concerns.
Sure, it got 10" screen and higher screen resolution, but that is it at all.
Keysight and Tek I didn´t know really at all.
Some might say it offers a 10bit ADC but there seem to be justified concerns if the RTB/RTM/RTA scopes by R&S are truly 10bit.
Trying is the first step towards failure - Homer J. Simpson
 
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Offline maginnovision

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Re: 350Mhz Scope, 2020
« Reply #69 on: May 07, 2020, 09:49:35 pm »
The Rode&Schwarz offering too less for the money, what RTB2000 series concerns.
Sure, it got 10" screen and higher screen resolution, but that is it at all.
Keysight and Tek I didn´t know really at all.
Some might say it offers a 10bit ADC but there seem to be justified concerns if the RTB/RTM/RTA scopes by R&S are truly 10bit.

I haven't heard about that, what are the justifications for the concerns?
 

Online Martin72

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Re: 350Mhz Scope, 2020
« Reply #70 on: May 07, 2020, 09:59:05 pm »
Plus the question, do I really need 10 bit...why and when….

Offline 0xdeadbeef

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Re: 350Mhz Scope, 2020
« Reply #71 on: May 07, 2020, 10:00:55 pm »
I haven't heard about that, what are the justifications for the concerns?
First of all, the higher end R&S offerings (like RTO2K) feature an 8bit ADC and use digital filtering to offer "up to 16bit" with reduced sampling rate. So it seems strange that the entry level scopes should offer a true 10bit ADC while the much more expensive models don't. I recently stumbled over a LeCroy document "Comparing High Resolution Oscilloscope Design Approaches" which goes in some detail how even the RTA4000 doesn't really provide 10bit noise performance. I'm fully aware that this document is written by a competitor but in contrast to the braindead Keysight marketing videos, it provides some technical background that seems to be valid to some degree.
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Offline maginnovision

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Re: 350Mhz Scope, 2020
« Reply #72 on: May 07, 2020, 10:07:44 pm »
The RTA/B/M are significantly newer so that just seems like conjecture if I've ever heard it. And saying the RTA doesn't offer 10 bit noise is also probably because the noise levels at higher levels can be worse than others. The old ENOB argument. That doesn't mean the ADC isn't 10 bits.
 
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Online Martin72

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Re: 350Mhz Scope, 2020
« Reply #73 on: May 07, 2020, 10:11:50 pm »
With the lecroy HDO6034A, we got a "true 12 Bit" scope plus a WR9054 ( 500Mhz, 8 bit).
Until now, I couldn´t detect any advantages between the both, 12bit vs 8bit.

 
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Offline maginnovision

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Re: 350Mhz Scope, 2020
« Reply #74 on: May 07, 2020, 10:16:12 pm »
With the lecroy HDO6034A, we got a "true 12 Bit" scope plus a WR9054 ( 500Mhz, 8 bit).
Until now, I couldn´t detect any advantages between the both, 12bit vs 8bit.

No but claiming the manufacturer is knowingly lying is a fantastic claim that requires proof, and if proven, companies typically have to pay to make things right.
 

Online nctnico

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Re: 350Mhz Scope, 2020
« Reply #75 on: May 07, 2020, 10:29:20 pm »
I haven't heard about that, what are the justifications for the concerns?
First of all, the higher end R&S offerings (like RTO2K) feature an 8bit ADC and use digital filtering to offer "up to 16bit" with reduced sampling rate. So it seems strange that the entry level scopes should offer a true 10bit ADC while the much more expensive models don't. I recently stumbled over a LeCroy
I'm not quite sure whether this is a good assumption. The entry level models have 2.5Gs/s ADCs where the higher end ones have 20Gs/s. Also the RTB2k and RTM3k are general purpose oscilloscopes where the RTO2k and up are more geared towards dealing with high-speed signals. For a general purpose oscilloscope which is likely used to look at small signals having a 10 bit ADC can be an advantage. High speed signals OTOH need active probes so signal levels are far less of a problem.

Edit: I just did a test on the RTM3004. The smallest step I can get (using sample-hold mode display) is consistent with a 10 bit ADC.
« Last Edit: May 07, 2020, 10:59:40 pm by nctnico »
There are small lies, big lies and then there is what is on the screen of your oscilloscope.
 
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Offline 0xdeadbeef

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Re: 350Mhz Scope, 2020
« Reply #76 on: May 07, 2020, 10:58:06 pm »
Well, let's not focus on the RTO2K then. The RTE1K was presented around late 2017 or early 2018 AFAIK, so about at the same time as the RTB/RTM/RTA lines. Its price starts slightly above the RTA4K with similar technical specs. Still, as the RTO2K, it uses an 8bit ADC but provides up to 16bit with digital filtering. AFAIK the only other R&S model with than alleged 10bit ADC is the hand held "Scope Rider".
But anyway, as others stated before, even a good 10bit ADC doesn't provide much benefit in most situations. A 10bit ADC with the baseline noise performance of an 8bit ADC in most gain ranges doesn't seem like a major benefit.
But sorry, this has gotten pretty off-topic.
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Offline EEVblog

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Re: 350Mhz Scope, 2020
« Reply #77 on: May 07, 2020, 11:19:25 pm »
Well, this workflow (zooming out after a capture) is available on many DSOs. It is the standard (or at least configurable) on Tektronix, Rigol, GW Instek, R&S, the older Keysight scopes (DSO7000A / B series and derivatives), the original Siglent SDS2000 series and probably several others. However you have to realise that 'capture outside' the screen only works if there is memory left over after filling the screen. So it won't be the case at time/div settings where the maximum samplerate  is dropped. I have been using DSOs like this forever. I strongly recall being very annoyed by the Siglent SDS2000 not remembering this setting in the early firmware.

Sorry, I stand corrected, I had a brain fart, you are right. Both Rigol (2000) and (modern Megazoom IV) Keysight do this, they will capture full memory depth and allow you to "zoom out" from a shorter time base trigger capture.
Siglent (5000X) however does not do this, it captures the screen and that's it, you can't "zoom out" either in STOP mode or single shot triggered mode.
The Siglent sampling architecture must be implemented very differently.
Through habit I guess I've just learned not to rely on this when capturing.

Now I'm curious to see a list of scopes that do this and those that don't. But this should have it's own thread.
 

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Re: 350Mhz Scope, 2020
« Reply #78 on: May 07, 2020, 11:23:03 pm »
But anyway, as others stated before, even a good 10bit ADC doesn't provide much benefit in most situations. A 10bit ADC with the baseline noise performance of an 8bit ADC in most gain ranges doesn't seem like a major benefit.

Sorry I don't agree. It's trivial to show examples where the 10 bit ADC in the R&S has advantages, I think I may have done this in one of my videos.
I won't argue that for most general uses it doesn't make a big difference, but it's really nice to have.
 
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Offline andrea.longobardi85

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Re: 350Mhz Scope, 2020
« Reply #79 on: May 08, 2020, 06:22:44 am »
Thank you all for your comments, I am inclined to go for the SDS5034X bundle, it doesn't seems the SDS2000X + has any advantages compared to the SDS5000X...
From your inputs the is seems R&S RTB2000, beside 10 bit ADC, doesn't have any significant advantage compared to the SDS5000x.
I do like the RTM3000 but it is out of budget I am afraid:) Thank you all!   
 
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Offline tautech

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Re: 350Mhz Scope, 2020
« Reply #80 on: May 08, 2020, 07:30:31 am »
Thank you for sticking around.  ;)

Anyways, based on my use of SDS500X and SDS2000X+, do get yourself a cheap USB mouse to compliment the physical UI and touch display as it certainly opens up a further dimension when using these DSO's.

Is the current probe an urgent requirement or will you take a while to seek out what you need ?
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Offline andrea.longobardi85

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Re: 350Mhz Scope, 2020
« Reply #81 on: May 08, 2020, 08:06:54 am »
I Guess I can wait a bit, although will be nice to know have some option in mind in case suddenly needed.
Any suggestion for a current probe >2MHz?
 

Offline Wuerstchenhund

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Re: 350Mhz Scope, 2020
« Reply #82 on: May 08, 2020, 08:12:56 am »
Well, this workflow (zooming out after a capture) is available on many DSOs. It is the standard (or at least configurable) on Tektronix, Rigol, GW Instek, R&S, the older Keysight scopes (DSO7000A / B series and derivatives), the original Siglent SDS2000 series and probably several others. However you have to realise that 'capture outside' the screen only works if there is memory left over after filling the screen. So it won't be the case at time/div settings where the maximum samplerate  is dropped. I have been using DSOs like this forever. I strongly recall being very annoyed by the Siglent SDS2000 not remembering this setting in the early firmware.

Sorry, I stand corrected, I had a brain fart, you are right. Both Rigol (2000) and (modern Megazoom IV) Keysight do this, they will capture full memory depth and allow you to "zoom out" from a shorter time base trigger capture.
Siglent (5000X) however does not do this, it captures the screen and that's it, you can't "zoom out" either in STOP mode or single shot triggered mode.
The Siglent sampling architecture must be implemented very differently.

Indeed, it seems the Keysight InfiniVision scopes perform the last sample at full max memory independent on the timebase.

The Rigols seem to do it when memory is set manually (well, the memory management is pretty basic).

However, Keysight Infiniium scopes (at least for DSO8k and newer) don't.

LeCroy scopes don't, and as Siglent follows LeCroy their scopes don't, either.

Tek MDO3k & Co do through a trick (leaving the timebase longer and zooming in when selecting shorter ones), other ones don't (I can't remember so I have to rely on 3rd paty info here).

R&S I don't remember but I don't believe they do.

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Through habit I guess I've just learned not to rely on this when capturing.

Now I'm curious to see a list of scopes that do this and those that don't. But this should have it's own thread.

Wouldn't this make a nice topic for one of your videos? Maybe coupled with a comparison of the nctnico method vs everyone else's method?  :-DD

I would watch that  :-+
 
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Offline Wuerstchenhund

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Re: 350Mhz Scope, 2020
« Reply #83 on: May 08, 2020, 08:17:26 am »
I Guess I can wait a bit, although will be nice to know have some option in mind in case suddenly needed.
Any suggestion for a current probe >2MHz?

Have a look at Hioki, they have various current probes and are also the OEM for many A brand probes:
https://www.hioki.com/en/products/list/?category=17

Based on your requirements (10A/10mA, >5MHz) the 3273-50 might be an option:
https://www.hioki.com/en/products/detail/?product_key=5717
 

Offline EEVblog

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Re: 350Mhz Scope, 2020
« Reply #84 on: May 08, 2020, 08:18:12 am »
Wouldn't this make a nice topic for one of your videos? Maybe coupled with a comparison of the nctnico method vs everyone else's method?  :-DD

What's his method again?, I must have missed that.
I just set the scopes max memory depth and a 1us timebase and STOP it. If it lets me zoom out to slower timebases and still show data then it passes.
Then repeat using a trigger signal just in case there is a difference between manual STOP mode and a trigger event capture.
 
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Offline tautech

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Re: 350Mhz Scope, 2020
« Reply #85 on: May 08, 2020, 08:28:39 am »
I Guess I can wait a bit, although will be nice to know have some option in mind in case suddenly needed.
Any suggestion for a current probe >2MHz?
Some but there rise time is not good and current vs frequency derating not very good either.

Maybe if you can find the cheap Pintek PA-699 in the EU it might just do your work:
http://www.pintek.com.tw/
Not to be confused with Pintech that have copied many Pintek products.

Otherwise good current probes are like good scopes....they cost a lot..... but maybe Dave could indicate more specs of the one he's looking at selling and how far away it might be.
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Offline 2N3055

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Re: 350Mhz Scope, 2020
« Reply #86 on: May 08, 2020, 08:33:35 am »
There is Micsig CP2100B current probe that looks interesting.. It's rather new and there are not many reviews yet.
It seems OK. It's 2.5MHz AC/DC 10/100 A probe. Maybe you can give a call to Batterfly and arrange test....
It has very good price. I have Micsig High voltage probes and they are working very well. Good quality so far.
 
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Offline Wuerstchenhund

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Re: 350Mhz Scope, 2020
« Reply #87 on: May 08, 2020, 09:23:12 am »
Get this for $2000 (he will accept an offer for $2k) and hack it:

https://www.ebay.com/itm/Agilent-Keysight-DSOX3014T-100MHz-4Ch-5GS-s-Oscilloscope-with-N2890A-probes/383339365915

So your solution for a 350MHz scope which is for professional use is to spend $2k on a second hand 100MHz scope and then void any chance of warranty and manufacturer support by hacking it? Seriously?

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The think is, that even if you buy the MSO5k, if you really want a Keysight or Tek, you will end up buying one of them as well.

Only if you're brand fixated. Which is quite common if you're a hobbyist.

If the scope becomes a tool that makes you money then price/performance and suitability for the tasks at hand count much more than brand image.
 

Offline maginnovision

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Re: 350Mhz Scope, 2020
« Reply #88 on: May 08, 2020, 05:48:39 pm »
In my case that's not true. If I pulled out initially to always see everything I'd spend more time calculating the timing measurements of the different signals than I would simply viewing the waveforms. Another issue I've run into is some scopes changing measurement resolution based on timebase in a way I lose the resolution I needed. I don't use $20k - $50k scopes though, I only need and use general purpose scopes. Maybe some more expensive scopes are better about that.
 
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Offline jemangedeslolos

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Re: 350Mhz Scope, 2020
« Reply #89 on: May 08, 2020, 06:56:47 pm »
Which Picoscope model do you have 2N3055?
It seems interessting to investigate  ;)
 
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Offline Gandalf_Sr

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Re: 350Mhz Scope, 2020
« Reply #90 on: May 08, 2020, 07:36:40 pm »
Is this the right forum for an argument?
If at first you don't succeed, get a bigger hammer
 

Online Martin72

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Re: 350Mhz Scope, 2020
« Reply #91 on: May 08, 2020, 08:09:46 pm »
There is Micsig CP2100B current probe that looks interesting.. It's rather new and there are not many reviews yet.
It seems OK. It's 2.5MHz AC/DC 10/100 A probe. Maybe you can give a call to Batterfly and arrange test....
It has very good price. I have Micsig High voltage probes and they are working very well. Good quality so far.

It seems to be an interesting thing for it´s Price(Batronix).
Like (almost?) other probes, it´s accuracy decreases when measuring higher currents(40-100Apk, 15%...), but comparing to other probes, much expensive ones, it seems to be a real bang for bucks thing.
 
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Offline maginnovision

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Re: 350Mhz Scope, 2020
« Reply #92 on: May 08, 2020, 08:15:28 pm »
Yes the spec is conservative but the typical isn't bad. Once you start hitting those high currents you're probably comparing to known good waveform or estimating power where it's probably good enough. If you really wanted you could probably characterize it yourself for the frequencies you need if it were a critical measurement and the low cost was important or made you feel better.
 
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Online nctnico

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Re: 350Mhz Scope, 2020
« Reply #93 on: May 08, 2020, 08:20:27 pm »
Is this the right forum for an argument?
For as long as people keep playing the ball and not the person there is no argument. Just an exchange of opinions and information.
There are small lies, big lies and then there is what is on the screen of your oscilloscope.
 
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Online Martin72

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Re: 350Mhz Scope, 2020
« Reply #94 on: May 08, 2020, 08:25:46 pm »
Yes the spec is conservative but the typical isn't bad.

Yepp, an interesting thing, makes me curious to compare it with our tek probes or lecroy ap011 at work and my owon cp05+ at home…

 
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Offline maginnovision

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Re: 350Mhz Scope, 2020
« Reply #95 on: May 08, 2020, 08:26:52 pm »
Yes the spec is conservative but the typhttps://jlcpcb.com/vical isn't bad.

Yepp, an interesting thing, makes me curious to compare it with our tek probes or lecroy ap011 at work and my owon cp05+ at home…

Sounds like fun!
 

Online Martin72

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Re: 350Mhz Scope, 2020
« Reply #96 on: May 08, 2020, 08:33:51 pm »
Slightly OT, but one more time:

At work I´m used to using the lecroy ap011 current probe, because it´s so handy.
Someday I used this for measuring switching current from an Inverter.
The next day, I must change for some reasons to the tek A6303, a 100A/2Mhz probe.
The ap011 got 120khz bandwith…
Boy, what a difference concerning the visible waveforms...
 
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Offline 2N3055

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Re: 350Mhz Scope, 2020
« Reply #97 on: May 08, 2020, 08:45:45 pm »
Yes the spec is conservative but the typical isn't bad.

Yepp, an interesting thing, makes me curious to compare it with our tek probes or lecroy ap011 at work and my owon cp05+ at home…
Yes, please!!! ^-^
 

Online Martin72

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Re: 350Mhz Scope, 2020
« Reply #98 on: May 08, 2020, 09:02:07 pm »
I´ll take the challenge, more to come in an separate thread, could last some weeks...
 
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Offline Someone

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Re: 350Mhz Scope, 2020
« Reply #99 on: May 09, 2020, 12:57:36 am »
So when nctnico says a scope can't do this very specific (and not fully explained) thing, just ignore it. Because with only a tiny change to any part of the application or acceptable solution, just about any scope will do the job.

Yeah, but he's not wrong.
It's an interesting and demonstrably potentially useful benefit.
But nctnico is wrong to generalise it as something other scopes can't do, because they can but in subtly different ways. Its a very narrow (and poorly/not defined) example to try and push some point like the marketing "comparisons" people keep laughing at.

The case of slow and infrequent triggers allows that type of use, and impedes/prevents acquisition of more rapid events (or they get lost in the long capture). Its a simple tradeoff (or "trap" as you might embellish it) that is chosen for the specific setting.

The inflammatory nature of this discussion has been the refusal of nctnico to acknowledge either the narrow applicability of the use case, or that it can be achieved by using a zoom window/view, or other methods.

Its a massive blow up over different methods to set the memory depth (auto vs manual vs implicit vs explicit).
 

Offline Someone

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Re: 350Mhz Scope, 2020
« Reply #100 on: May 09, 2020, 01:01:09 am »
Yet it's arguably DSO user error when any capture is required that an appropriate timebase was not previously selected.

No. I'm talking about legitimately setting the timebase to capture the thing you wanted, no user error. Then perhaps you saw something unexpected and though "gee I wonder what happened before or after that".
I understand what are you saying, but when working on, say,  CAN bus, what are the chances you will happen to capture exactly packet with error if you looking at single edge? You don't capture that way looking at that kind of data. You use larger time period, with hundreds of packets and then search and scroll and zoom in and out.

You can't say you understand what I'm saying then immediately go into an example where it's not going to be of value. That is completely opposite to my point!
I'll repeat, there is no logical argument you can make to say that this isn't a potentially useful feature in some circumstances.
Yes, but as these seem to keep coming back to:
Poster A says a scope is not worth considering because it can't do some very specific feature..... not mentioning how that feature might be useful or what situations might make it applicable.
Poster B points out the holes in their point and explains other comparable methods.
Poster A keeps narrowing the goalposts to be "right"

Time was wasted by all and a confusing mess is left behind. The generalised answer is there are many corner cases for test/measurement and they generally aren't applicable unless that matches the users application.
 

Offline EEVblog

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Re: 350Mhz Scope, 2020
« Reply #101 on: May 09, 2020, 01:01:41 am »
NOTE: I've split this topic out to a new thread. Got most of the posts I think.
https://www.eevblog.com/forum/testgear/oscilloscope-zoom-out-quirk/
 
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Offline tautech

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Re: 350Mhz Scope, 2020
« Reply #102 on: May 09, 2020, 01:14:47 am »
NOTE: I've split this topic out to a new thread. Got most of the posts I think.
https://www.eevblog.com/forum/testgear/oscilloscope-zoom-out-quirk/
Not quite and the word Capture needs be added to the new thread title.
« Last Edit: May 09, 2020, 01:16:59 am by tautech »
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