Sorry, this was originally posted as a reply to Simon's reaction, where it doesn't belong. This is a nice explanation for real-time sampling but almost all but the very cheapest modern 'scopes are capable of performing "equivalent time sampling" (ETS). This implies that, unless I'm very mistaken about what the 'scopes in the video are capable of, assumed relations in the video between the not-so-steep edges and their "limited" maximum real-time sample rate do not exist. The edge speeds shown are limited by generator capabilities, 'scope analog bandwidth and impedance matching. No relationship exists between maximum sample rate and "analog" bandwidth, if the ETS is high enough. The reason for this is that using equivalent-time sampling, multiple periods of a signal together are used to construct one waveform for displaying. Samples from multiple sampling periods are interleaved. Only the sampling time, i.e. the time the 'scope looks at each and every individual sample, must be short enough. This interleaving has nothing to do with AD converter(s) being interleaved. Using ETS, the highest frequency that can be shown isn't at all dependent on a 'scope's maximum real-time sample rate nor its storage rate. ETS is usable on any repetitive signal, if the 'scope supports it. That's why even many really old 70k Sa/s (yes!) sampling 'scopes show a signal's 50 ps rise time, no problem, just not "single-shot", i.e. not if a one-time event. Many early digital 'scopes had such low sample rates that sampling a waveform of even as low as say 10 MHz in one go wouldn't have been possible. ETS can be many hundreds of times the maximum real-time sample rate. With most "serious" modern DSO's, maximum real-time sample rate is shown on their front. A bit more technical: The Nyquist limit applies to the number of samples necessary to define one complete sinusoidal period (not an edge) and does not apply to ETS in that way.
Gets all complicated with Nyquist frequencies when running out of sample rate. Well explained Tony. When using fast risetimes on the scope termination becomes very important.
The Siglent oscilloscopes: SDS1204X-E 4 Ch 200MHz, SDS1104X-E 4 Ch 100MHz, SDS1202X-E 200MHz 2 Ch, all are [1 GSa/s], and no faster option. memory depth varies. 7 Mpts/CH (non-interleaved) 14 Mpts/CH (interleaved) I am not sure if the 200MHz scope is the way to go? 😎 Thank you Tony. Great information.
Yes i love the Siglent, i have de 1202X-E and it is so easy to operate. i am now looking for the 2202X-E that can be upgraded to 350 MHz and has bodeplot.
The 5 measuring points per period are correct, but these points are always positioned differently. They are not always in the maximum, minimum and zero crossing. Now it depends on the intelligence of the firmware to interpret a waveform here. You can also switch the presentation from vector to dots to see the sample points. I also find the oscilloscope's memory depth to be important in order to save the samples over a larger time frame. The OWON has options in the menu to minimize this restless display. A very nice representation of these parameters, great video 👍
Hello and thank you, yes i over-simplefied thinks just for example, in the end test test shows what really happends, thank you for the extra information.
Thank you George, there is more, also Rise-time and Slew-rate, but when making this video i did not have my Fast-Risetime generator yet, but never the less it gives you a nice idea.
My first test equipment was a RIgol 1054Z. Great machine, but when I began my UHF vintage lab it becomes a secondary friend, I use the SA a lot more. The Rigol is still useful for tiny signals inside of the big fellas from HP :) great video Tony
Thank you Chris! ,. and thank you and Simon for mentioning my Channel on your live stream. Loved the stream, you have a nice group of people around you.
Hi Tony, I like your videos (and your efforts to connect all and everything to your 10 MHz time base) 😀 One not so expensive suggestion for front end measurements of scopes. When I got my new Siglent SDS2000x plus I was keen to measure the “new” bandwith via rise time. But no generator I own was able to provide the needed fast pulses. From the EEVblog forum I got the hint to buy a Leo Bodnar pulser. It came with a measured rise time of about 50 ps. Than it is easy and more reliable to check the BW of the front end of your scopes.
Thanks that is a good tip! Leo has some nice stuff, his gpsdo also seems very popular. this setup was mostly to show that when the scope has 20MHz printed on it, it does not necessarily mean you can measure any 20MHz signal.
Good video Tony. I've been thinking of getting a new modern scope but there is definitely more to buying one than just the MHz specifications. For the things I work on, old radios and test equipment, probably not much effect with the bandwidth limitations but still very interesting to see this demonstrated. Regards - Andrew
Maybe you could turn off the interpolation sin(x)/x to show the real signal. I do not know what options these scopes have. I know Tekronix has for example the Dots-only mode, where you an see the actual samples. There should be at least 2 ways to interpolate, sin(x)/x and Linear. We can see in your video that the scope is using the sin(x)/x interpolation. At the end you end up with a sinus signal no matter what signal you put in. An analogue scope would have a similar problem. Not using the interpolation, but the rise time decay/limit would also make a sinus out of a square wave if freq. high enough. But I suppose you could go much further above the bandwidth. The amplitude would go gradually down of course. Nice scopes those Siglents. No Owen for me 😁
I have 2 keysight and agilent e9327 power sensor zeroiyis ok but calibration error how can i fix it Power meter agilent epm series one but it work properly
Sorry, this was originally posted as a reply to Simon's reaction, where it doesn't belong.
This is a nice explanation for real-time sampling but almost all but the very cheapest modern 'scopes are capable of performing "equivalent time sampling" (ETS).
This implies that, unless I'm very mistaken about what the 'scopes in the video are capable of, assumed relations in the video between the not-so-steep edges and their "limited" maximum real-time sample rate do not exist. The edge speeds shown are limited by generator capabilities, 'scope analog bandwidth and impedance matching.
No relationship exists between maximum sample rate and "analog" bandwidth, if the ETS is high enough.
The reason for this is that using equivalent-time sampling, multiple periods of a signal together are used to construct one waveform for displaying. Samples from multiple sampling periods are interleaved. Only the sampling time, i.e. the time the 'scope looks at each and every individual sample, must be short enough.
This interleaving has nothing to do with AD converter(s) being interleaved.
Using ETS, the highest frequency that can be shown isn't at all dependent on a 'scope's maximum real-time sample rate nor its storage rate. ETS is usable on any repetitive signal, if the 'scope supports it. That's why even many really old 70k Sa/s (yes!) sampling 'scopes show a signal's 50 ps rise time, no problem, just not "single-shot", i.e. not if a one-time event. Many early digital 'scopes had such low sample rates that sampling a waveform of even as low as say 10 MHz in one go wouldn't have been possible.
ETS can be many hundreds of times the maximum real-time sample rate. With most "serious" modern DSO's, maximum real-time sample rate is shown on their front.
A bit more technical: The Nyquist limit applies to the number of samples necessary to define one complete sinusoidal period (not an edge) and does not apply to ETS in that way.
Thank you Raymond, some good extra information!
Отличное видео с примерами в нюансах работы цифровых осциллографов..
Thank you so much sir!
Dank u wel Tony.
Jij ook bedankt voor het bericht!
Gets all complicated with Nyquist frequencies when running out of sample rate. Well explained Tony. When using fast risetimes on the scope termination becomes very important.
Thank you Simon! yes i terminated with an inline terminator on the last scope on the Siglent. a nice shiny one..
The Siglent is clearly in a different league, thanks Tony.
great!
The Siglent oscilloscopes: SDS1204X-E 4 Ch 200MHz, SDS1104X-E 4 Ch 100MHz, SDS1202X-E 200MHz 2 Ch, all are [1 GSa/s], and no faster option.
memory depth varies. 7 Mpts/CH (non-interleaved) 14 Mpts/CH (interleaved) I am not sure if the 200MHz scope is the way to go? 😎 Thank you Tony. Great information.
Yes i love the Siglent, i have de 1202X-E and it is so easy to operate. i am now looking for the 2202X-E that can be upgraded to 350 MHz and has bodeplot.
Wow! Great vid. I feel like I never understood anything at all until now 😂
Very nice! Nice shirt too 😀
Thanks :)
The 5 measuring points per period are correct, but these points are always positioned differently. They are not always in the maximum, minimum and zero crossing. Now it depends on the intelligence of the firmware to interpret a waveform here. You can also switch the presentation from vector to dots to see the sample points. I also find the oscilloscope's memory depth to be important in order to save the samples over a larger time frame. The OWON has options in the menu to minimize this restless display. A very nice representation of these parameters, great video 👍
Hello and thank you, yes i over-simplefied thinks just for example, in the end test test shows what really happends, thank you for the extra information.
The best experiment so far!
Thank you George, there is more, also Rise-time and Slew-rate, but when making this video i did not have my Fast-Risetime generator yet, but never the less it gives you a nice idea.
Real eye-opener!.....Many thanks for explaining and showing this!
Glad it was helpful!
My first test equipment was a RIgol 1054Z. Great machine, but when I began my UHF vintage lab it becomes a secondary friend, I use the SA a lot more. The Rigol is still useful for tiny signals inside of the big fellas from HP :) great video Tony
Thank you! oyeah the SA is some nice equipment for sure!
Very good video!
Tony ,Keep on with the GOOD WORK!
Thanks!!
Lovely to see all your oscilloscope. I only have 17 so room for a few more I think.
Thank you Chris! ,. and thank you and Simon for mentioning my Channel on your live stream. Loved the stream, you have a nice group of people around you.
Very very good! A minimum of water, a maximum of facts.
Thank you.
Thank you!
Owon is not bad for budget hobbyist. The Siglent is much higher quality. Very good video.
Thank you!
Hi Tony,
I like your videos (and your efforts to connect all and everything to your 10 MHz time base) 😀
One not so expensive suggestion for front end measurements of scopes.
When I got my new Siglent SDS2000x plus I was keen to measure the “new” bandwith via rise time.
But no generator I own was able to provide the needed fast pulses.
From the EEVblog forum I got the hint to buy a Leo Bodnar pulser. It came with a measured
rise time of about 50 ps. Than it is easy and more reliable to check the BW of the front end of your scopes.
Thanks that is a good tip! Leo has some nice stuff, his gpsdo also seems very popular. this setup was mostly to show that when the scope has 20MHz printed on it, it does not necessarily mean you can measure any 20MHz signal.
www.eevblog.com/forum/projects/yet-another-fast-edge-pulse-generator/
worth reading and worth another video
Loved the video, good content and now i know how good the owon oscilloscopes are.
Thank you..
this was quite helpful.
i've been shopping for a cheap hobbyist bench setup as i'm mostly working with audio and some digital signals (
the whole time i was thinking of that xiph.org video about digital audio sampling, and how similar that is to this.
Thank you very much!!.. the accent will not change to much i am affrait, maybe i will find i better Mic.. but am improving little by little.
Excellent demo, very useful, thank you.
Thanks!..
Good video Tony. I've been thinking of getting a new modern scope but there is definitely more to buying one than just the MHz specifications. For the things I work on, old radios and test equipment, probably not much effect with the bandwidth limitations but still very interesting to see this demonstrated. Regards - Andrew
Thanks andrew! not a tek 475 for you? 😁
@@TonyAlbus I have a silly number of scopes! No totally digital ones though, a HP 56421A and 54601A are the nearest
@@Andrewausfa Wow!.. that is some nice gear!
Maybe you could turn off the interpolation sin(x)/x to show the real signal. I do not know what options these scopes have. I know Tekronix has for example the Dots-only mode, where you an see the actual samples. There should be at least 2 ways to interpolate, sin(x)/x and Linear. We can see in your video that the scope is using the sin(x)/x interpolation. At the end you end up with a sinus signal no matter what signal you put in. An analogue scope would have a similar problem. Not using the interpolation, but the rise time decay/limit would also make a sinus out of a square wave if freq. high enough. But I suppose you could go much further above the bandwidth. The amplitude would go gradually down of course. Nice scopes those Siglents. No Owen for me 😁
Yes indeed something to try... oh yes Owon or Siglent easy choice for sure.
Very, very interesting !
Thank you
grate video thanks sir
Thank you!
I have 2 keysight and agilent e9327 power sensor zeroiyis ok but calibration error how can i fix it
Power meter agilent epm series one but it work properly
someone say diode ditector burent out cant we fix it
Hello, i am not familiar with power sensors, maybe a Agilent service center can help?
sweet collect man
Thanks!
Siglent use persitence mode by default that's why the signal looks better
agree it looked better on the Siglent, whatever trick they did.
👍🎖🎖🎖🎖🎖
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