What you taught in 10 minutes took me ten years to learn on my own. Until now, I harbored the notion that NRZI had something to do with the uniformed arrangement of the bitstream.
Dude, this was super awesome and resourceful! I am learning about eye diagrams for PCIe retimers. Your explanations help really narrow down what they speak about with signal loss.
I started taking a passive interest in DSP and signal processing about two years ago, when I picked up my first RTL-based sdr and started decoding trunked radio and other digital modes. I've seen many of these eye charts and constellations since then but nobody ever takes the time to explain how they work, which i can understand, but it can be frustrating. So thank you for putting together a simple and extremely clear explanation of these figures and how they are useful.
This explanation is great! I'm not speaking english natively and you have explained this better than my electrronic proffessors in my native language years ago. Thank you : )
As ALWAYS, EXCELLENTLY explained, I myself never knew about the eye pattern, having worked with serial interfaces, anyway as usual THANKS and keep them coming!
Alan I wish you would not keep using that MDO4000 I get serious scope envy:) I also have a request. Would you consider doing a video on coax matching stubs and line theory and maybe Smith charts. I was a what you would call a tech class amateur many years ago and this was one area I never really got to grips with. Thanks for all the great videos so far I think I have learnt something from every single one. It's obvious why Tek employ you in your position, clear and concise instructions.
wow, What has the world come to when THE TEACHER googles or you tubes the answer before delivering the lesson.........My God !!! I mean... Great that god use out of this, but.. You're the teacher, You're supposed to know. Just like i'm an Engineer, I'm supposed to know. And i do We are both here for different reasons, Mine is .. I like to browse videos with scopes in them and see who's doing what. but the difference is.. You don't see me saying thanks, now i'll show this to my students I'm just beside myself with your comment.
You answered one of my nagging questions on eye patterns: how to trigger without access to the source (or destination) clock. Is this why it's often cited to reference the third unit interval? Thanks for the very concise and helpful video!
BPSK, QPSK, etc. are all RF modulation types, and thus don't have visible eye patterns directly when looking at the RF signal. When demodulated back to baseband data, then there is an eye pattern that you can view. This requires vector signal analysis or modulation analysis capability that most people aren't going to have available to them. Of course, looking at the output of a receiver that is demodulating these signals will give you an eye pattern too.
Jones Panicker Sure, that shows the resulting eye pattern after filtering and demodulation. The actual BPSK modulated carrier signal looks more like this: electronicdesign.com/site-files/electronicdesign.com/files/archive/electronicdesign.com/content/content/64598/64598_fig02_inline_cropped.gif
That eye would come from performing a phase demodulation on a BPSK signal, using a phase detector or phase locked loop demodulator, or something similar. This would give the baseband digital bit stream which could then be displayed as an eye diagram per this video.
Hi Alen. A great tutorial. I would like to ask you if it is possible to see the eye pattern of a DVB-ASI signal by directly connecting the signal from source bnc connector to this Oscilloscope's input? Can it be possible to see the digital signals in a DVB-ASI source with this Oscilloscope by a bnc to bnc connection? Thanks!
Nice tutorial Alan, but the MDO4k scope, cost around £17,000 ($29,000 US), do you think you could give your tutorials with something hobbyists actually own? Even a Saleae?? Cheers.
The MDO4000 series starts under $10K US, MDO3000 start about $3K US. However, eye patterns like this can be displayed on just about ANY scope, even analog CRT based scopes. As long as the scope has some form on waveform persistence, eye patterns can be displayed. I used the MDO4000 because it's large screen shows up on video very well.
***** hey, don't get me wrong, if I had an MDO 4k I'd be using it too, however, even at $3k for a scope, that's out of reach for your average maker/hobbyist - a $99 scope or saleae is more likely to be in their kit, and so your excellent tutoring would resonate ;-)
i really got some quality information by this video, and i hope you give me some information to generate an eyepattern in matlab , that would be helpful for me. thank you
What you taught in 10 minutes took me ten years to learn on my own. Until now, I harbored the notion that NRZI had something to do with the uniformed arrangement of the bitstream.
This is the best explanation on Earth. Learning by doing is really a thing!
May i use screenshots from your video on my Quora channel? I will give your reference as well.
Well explained as usual. Thanks, Alan. You are a RUclips treasure.
Great video. I am an electronic engineer for 8 years and this is the best explanation for an eye diagram so far
I read a couple of articles explaining the eye pattern, but none of them is as clear as yours, thanks a lot
Thank you for this great explanation. You are now referenced in my graduation paper!
Dude, this was super awesome and resourceful! I am learning about eye diagrams for PCIe retimers. Your explanations help really narrow down what they speak about with signal loss.
Incredible explanation, shown on a real example - just what I needed, thank you!
great video, reading about eye pattern is nothing compared when you see real experiment with great explanations. thanks
This video really helped me out on understanding the eye. A very nice way of building up the information. Thank you!
I started taking a passive interest in DSP and signal processing about two years ago, when I picked up my first RTL-based sdr and started decoding trunked radio and other digital modes. I've seen many of these eye charts and constellations since then but nobody ever takes the time to explain how they work, which i can understand, but it can be frustrating.
So thank you for putting together a simple and extremely clear explanation of these figures and how they are useful.
This explanation is great! I'm not speaking english natively and you have explained this better than my electrronic proffessors in my native language years ago. Thank you : )
Wow what a great explanation, shame i graduated before finding your videos.
I feel the same!
U r d best,,, I searched a lot,,, many websites, for complete setup, to take reference for testing my board, u r d only one who showed complete setup
Excellent. As a novice I found your video the best explanation of the eye pattern on the oscilloscope. Thanks for posting it.
As ALWAYS, EXCELLENTLY explained, I myself never knew about the eye pattern, having worked with serial interfaces, anyway as usual THANKS and keep them coming!
Thank you very much Sir. Your video helped me to reproduce the eye pattern at different frequencies for my presentation.
Alan, I always enjoy your videos, but I really enjoy the ones where you repair a transceiver or other piece of ham electronics. Keep up the nice work!
Please do more eye pattern videos. A digial radio signal would be an excellent real world example.
Such a great video! Thanks
Incredibly educational video. Much appreciated.
Alan I wish you would not keep using that MDO4000 I get serious scope envy:)
I also have a request. Would you consider doing a video on coax matching stubs and line theory and maybe Smith charts. I was a what you would call a tech class amateur many years ago and this was one area I never really got to grips with.
Thanks for all the great videos so far I think I have learnt something from every single one. It's obvious why Tek employ you in your position, clear and concise instructions.
I'll add those ideas to my list of future topics. I did touch on quarterwave stubs in my video on Tracking Generators...
+1 For the Smith charts
Thank you!!... I followed step-by-step your procedure in my MDO3024. Ready for a practical class with my students!
wow, What has the world come to when THE TEACHER googles or you tubes the answer before delivering the lesson.........My God !!!
I mean... Great that god use out of this, but..
You're the teacher, You're supposed to know.
Just like i'm an Engineer, I'm supposed to know.
And i do
We are both here for different reasons, Mine is .. I like to browse videos with scopes in them and see who's doing what.
but the difference is.. You don't see me saying
thanks, now i'll show this to my students
I'm just beside myself with your comment.
You answered one of my nagging questions on eye patterns: how to trigger without access to the source (or destination) clock. Is this why it's often cited to reference the third unit interval? Thanks for the very concise and helpful video!
I thoroughly enjoyed it and learned something new about the process. Thanks for sharing!
Good visual argument for Manchester encoding.
Very clear and concise explanation, thanks.
Thank you very much for this. Very informative.
Excellent explanation and video. Thanks so much!
Thanks Alan.
Its really a very usifull video for a b.tech 3rd year studentThank u very much sir
Thank you.Great video. Finally understood Eye Patterns
This was awesome, thank you very much'!
searched so far to find explanation ! can you do some video on how to drive differential signal with FPGA ?
Nice job! Thanks so much for posting this.
right, now I get it! Thanks!
Outstanding explanation, thank you.
Another excellent video .. Thanks!
This is really informative.. Thanks a lot for sharing
Very informative video as always. Thank You.
Maybe you could some time do a video on I\Q data, modulation?
Yes, a video on IQ data and quadrature modulation has been on my to-do list for a while!
Great explanation
It's a really good video. Thank you.
Very instructive. Thanks.
Thank you very much, very informative video
Super Great Video! in case of TDS2000 scope, howto setup proper parameters to view eye pattern? thanks agian.
Great explanation! Thank you!
Whow, great explanation.
excellent video. it would be great if you could show the eye patterns of bpsk, qpsk all compared...
BPSK, QPSK, etc. are all RF modulation types, and thus don't have visible eye patterns directly when looking at the RF signal. When demodulated back to baseband data, then there is an eye pattern that you can view. This requires vector signal analysis or modulation analysis capability that most people aren't going to have available to them. Of course, looking at the output of a receiver that is demodulating these signals will give you an eye pattern too.
how about this then? en.wikipedia.org/wiki/File:Binary_PSK_eye_diagram.svg
Jones Panicker Sure, that shows the resulting eye pattern after filtering and demodulation. The actual BPSK modulated carrier signal looks more like this: electronicdesign.com/site-files/electronicdesign.com/files/archive/electronicdesign.com/content/content/64598/64598_fig02_inline_cropped.gif
hmm. but i don't understand how en.wikipedia.org/wiki/File:Binary_PSK_eye_diagram.svg came about. if anyone could explain that it would be great.
That eye would come from performing a phase demodulation on a BPSK signal, using a phase detector or phase locked loop demodulator, or something similar. This would give the baseband digital bit stream which could then be displayed as an eye diagram per this video.
Hi Alen. A great tutorial. I would like to ask you if it is possible to see the eye pattern of a DVB-ASI signal by directly connecting the signal from source bnc connector to this Oscilloscope's input? Can it be possible to see the digital signals in a DVB-ASI source with this Oscilloscope by a bnc to bnc connection? Thanks!
Super helpful! Thank you!
Thanks Alan: Cheers, Mark
Never understood the topic like this
Thank you! This was great :)
Thank you sir!
Thanks Alan
The inventor of the Eye Patten has passed away 4/25/22 RIP Dennis
Address bus can be degraded by EMC components ( RF cokes ) ,and detected by eye pattern. Thanks
Thank you.
Thanks!
Nice, thanks
I notice that the "mokay" was gone also, so double thumbs up.
Nice tutorial Alan, but the MDO4k scope, cost around £17,000 ($29,000 US), do you think you could give your tutorials with something hobbyists actually own? Even a Saleae??
Cheers.
The MDO4000 series starts under $10K US, MDO3000 start about $3K US. However, eye patterns like this can be displayed on just about ANY scope, even analog CRT based scopes. As long as the scope has some form on waveform persistence, eye patterns can be displayed. I used the MDO4000 because it's large screen shows up on video very well.
***** hey, don't get me wrong, if I had an MDO 4k I'd be using it too, however, even at $3k for a scope, that's out of reach for your average maker/hobbyist - a $99 scope or saleae is more likely to be in their kit, and so your excellent tutoring would resonate ;-)
Thanks
i really got some quality information by this video, and i hope you give me some information to generate an eyepattern in matlab , that would be helpful for me. thank you
If you have a vector of simulated serial data, then you can plot it vs. a sawtooth waveform that you can create using the mod() function.
whether data should be in binary? and why only sawtooth..
Sawtooth is the X variable - this is what will help you to overlay consecutive groups of bits on top of each other.
I'll ask Dennis what he thinks of your video.
What usb test board and how to wire it??
The test board used is a DPO DEMO 2 test board that Tektronix made as a demonstrator aid for their oscilloscopes.
kool scope
so is this similar to mask testing?
Yes, masks are often used in conjunction with eye patterns.
Eye patterns rule.
👍👍👍🙏
Going to fast
I want that scope, give it to me please....buy urself a new one...u seem like a rich guy...I know u can afford it.
I can't even afford this one! It belongs to my employer...
I forgive the fancy equipment because you occasionally break out the modest Heath 4552 (which is all I have! ).
***** In fact - I'm thinking about doing a video on scope calibration using that 4552 as the subject scope, since it is relatively simple and basic.
Real great explanation and well made video very understandable. Thank You fellow ham for education videos really learn a lot and very enjoyable wb7qxu
Very informative, thank you!
Thanks!