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5 scopes, spectrum analyzer, signal generator. And i'm sitting here with my tiny soviet analog scope.

14:40 - "It looks like dick and balls". You don't make me laugh very often but when you do, I laugh hard.

Small correction: It does not compute the general DFT algorithm, but the FFT is the algorithm that it uses. That is why the FFT-points are always in always a power of 2^n, due to the nature of the FFT algorithm. The general Discrete Fourier Transform does not have this limitation, but takes far more computing power.

As folks have mentioned, the DS1054Z is capable of a lot better - but it's a trick since you can't directly set the sample rate and adjusting the center frequency can take a lot of knob twisting. On Dave's signal you are shooting for a sample rate of 5Msps to see a symmetric plot or 2 if you want a better plot that just shows the left side (nothing past 1MhH). Use auto to get a nice stable waveform and fine adjust to fill the screen vertically. Under acquisition set the depth to the first value larger than 16k (depending on whether you have 12 or 24M of memory). The FFT memory mode supports 16K samples so there is no benefit to more depth. I can't see a difference between normal/ave/hires but peak doesn't seem to work well. Under the math function turn on FFT and select Hanning window and memory FFT (rather than screen FFT) on the second settings page. The trick at this point is to walk the sample rate down to 5Msps one step at a time by adjusting the horizontal timebase (CCW). Set FFT Hz/Div to its largest available value and the center frequency to 1Mhz. If you don't keep the Hz/Div at max or you skip steps it can take a million turns to move the center frequency. Always adjust the center even if it shows 1Mhz because it LIES and sometimes doesn't update when you change the timebase. Once you've gotten the sample rate down to 5Msps and the center at 1Mhz you can reduce your Hz/Div to 5k. If you get to a point where the center won't go to 1Mhz check that you are still in memory mode with Hanning window. It sometimes returns to defaults for no apparent reason. Check these again at the end just to be sure because the plot will be terrible if Hanning is off. Adjust the vertical size/position of the plot and you are done.

Great job as always. One need consider the cost of each DSO, parenthesis price is list price, otherwise discounted: Rohde & Schwarz HMO1202 Series;1232 $US2300 Tektronix MDO3000 as shown MDO3014 (US$4,110) Keysight 3000X Touch, MSO 3054T ($13,000) Lecroy WaveJet 354 Touch $US5000 GW Instek GDS-1104B $700 ($830) Rigol as 1054z ($US400) Rigol DS2000 as DS2202 ($US1790) You'd expect the more expensive DSOs to give you an FFT closer to a SA but it seems the bang for buck maybe the Instek as despite its poor appearing UI, its keystrokes are similar to the Tek FFT shown. The 2 CH or 50 MHz version street price for much under $400 and is identical except for firmware crippled bandwidth and reduced analog channels.

We have 5 scopes, a spectrum analyzer and a function generator, its dark and we are wearing sunglasses... lets go

14:40 "It looks like dick and balls!" I laughed way too hard at that :D

If a scope doesn't have enough computational power for a good DFT one thing you can do is transfer the waveform to a computer and do the DFT with LabVIEW, or some other software. It's been a long time since I've done this, but I think I remember it working really well.

We used to have some old school 400 MHz scopes when I was in the military. Loved those old CRT displays. I have worked on modern FFT digital scopes...but, not as much raw fun as the old ones. Cheers!

Dave you need to go to page 2 on the FFT and set it to MEMORY Mode when using the FFT or your just looking at the TRACE data. The memory will have a tremendous amount more info to calculate the FFT off and will give a great result! Also set to 5ms on the horizontal!! This is for the Rigol DS1000z of course.

thanks for great info as usual sir....

14:41 Isn't that what dB stands for ???

The Department of Redundancy Department would like to speak with you regarding your FM modulation.

Hi Dave, nice comparison. Just FYI, at 8:50 on HMO, you can actually toggle Horizontal control from FFT to time waveform by pressing on the Time/Div knob. Then you will notice, HMO can also do gated FFT. Btw, apart from the ease of use across different entry level scope, it would be nice to compare on FFT performance on accuracy, noise floor and bandwidth flatness.

Thanks Dave!

Nice video as always. One little technicality: at 4:35, you asked whether the FFT is done as a discrete Fourier transform (DFT). The answer should be yes no matter what, because FFT (Fast Fourier transform) is an algorithm that computes a DFT in a computationally efficient way. A DFT is by definition for discrete signals, i. e. lists of numbers. This is not 100% the same as a regular Fourier transform (defined on continuous signals), but of course mathematically these concepts are closely related.

exactly what I needed thanks!

Yep, carrier nulls at mod index values of 2.405 and others - great way to set transmitter deviation and to calibrate deviation meters. Good demo.

Great video, thanks.

Good video!

hi, was your rigol original or "hacked", so with full bandwidth? or doesn't the number of points have anything to do with the limited functions of the "base" unit?

Johann Carl Friedrich Gauss - pure genius discovered FFT, but didn't have much application for it. FFT was rediscovered for cold war nuclear disarmament verification and useful for a million other things! Very in formative as usual, Dave - we all owe you big time - Merry Christmas!

I have been going back and watching some of the older EEVblog educational video's as they are great. I know these EEVblog videos

Dave, great vid as always. I picked up a 1054Z last year but wasn't aware of its limited FFT function. With regards to audio, 20Hz-20kHz, is this scope still lacking severely or is it suitable for analyzing components within an audio circuit..ie, cables, etc? Pr should I look to a dedicated spectrum analyzer. Thanks

The somewhat higher end Rohde & Schwarz RTE and RTO scopes really blow all these out of the water with their FFT. It was one of the main selling points that made me settle on an RTE for my lab.

Fundamentals Friday: how works a spectrum analyser and digital FFT. I love your Videos .

We like it when you waffle on Dave it shows real passion for what you know and love

Great comparison, even when you called my scope a toy. I wonder how fast it would get if use a computer loading data through USB and doing fft on the full sample window.

Reuters latest. 21.07 GMT. Confirmed reports arrived this evening showing Dave Jones actually ''turning it on'' before taking it apart. A group of investigators from Interpol arrived in Sydney this morning and went directly to the offices of Mr Jones. Any repercussions will be reported here and it is expected he (Mr Jones) will defend his position with a stuffed wombat, as usual.

I don't know what any of the words you say mean but I can't stop watching these videos.

Dave, visually the carrier frequency and sidebands seem fine, but how accurate are the amplitudes on each scope? Any different detector settings on those scopes? What are the noise floor levels on each scope? Kudos on the video :)

more scopes?

Hey Dave, are you running the latest firmware on that Tek? I remember there was a firmware update to fix RF self-test failure if there was a signal present on startup.

the exposure thingy setting actually looks really good to me! isn't that's how we see things?

Dave, how about a video for probing techniques video? Most guys like me don't know which probing method to use in which situation.

I like Dave's "quick look"!

I believe the Textronics does the FFT on ALL of the sample points. If you reduce the number of sampling points, then the resolution of the FFT is decrease and the speed is increased. I believe 100K works rather well.

wow thank you dave you have cured me of my lust for a tek 3000 mdo scope one less thing 2 want

Dave, you've gotta lock the focus when filming screens! Just a tip :)

DAVE , what about a review of RIGOL 4000 series? any plans to do one?

the lecroy one seems to show a middle finger instead of the real deal

Dave creams himself over the 128kpt R&S FFT and takes a huge dump on the GW Instek 1Mpt FFT. I'm guessing Dave is looking to score some sweet sweeet R&S free test gear for his lab.

Do any of them display the phase information of the DFT? (as opposed to just the magnitude of the complex transform?)

I found a way to make the rigols output much more usable: In the second menu panel of math go to "mode" and set it to "memory" instead of "trace". Then in the "acquire" settings menu, set the memory depth manually to a higher value. The result isnt top quality, but at least better than with the default settings

On the Rohde & Schwarz, in FFT mode, just push the timebase knob to switch between frequency view, signal view and window adjust.

Hey this is not related to this topic, but what did you do with ya old pc ??

Hi Dave, what is that piece of rack mount equipment on your shelf?

Dave on that Rigol 1000 zed did you have all the upgrades and the latest firmware? If not is it possible you could do the upgrades and firmware and show FFT again please.

How useful would DS1054Z be in the 20-20khz range, I understand with 1mhz center point example..but would it show data points in the lower frequency range? Or would it again only show the carrier frequency and not much detail? Interested in using it just for the audio spectrum, so curious how it works between 20hz to 20khz ...

The Rigol is displaying at 25kHz /Div (300kHz/Span) as opposed to 5kHz (50kHz) with the Rode und GW. Why?

The Keysight version apparently can display Min Hold, Max Hold and Average from your screenshot. Was hoping that you can demonstrate that though.

Hi Dave, not sure if you have a Siglent scope. How does this one hold up WITH FFT. second question, I am a electronics hobbyist and software engineer by trade. What oscilloscope would you recommend for us hobbyists. Thanks keep up the good work. PS apologise if you have covered siglent scope already, if so point me in the right direction.

Dave, did you check to see if every scope was running the latest firmware /os before the test?,,because there could be a lot of changes with that if the fft run in the cpu

Those Hameg 'scopes are really good, the FFT arent that bad either, at least not for low frequency use :) VonHann was fun, what were they thinking?

woooww

Hey Dave, ever got your hands on a Yokogawa DLM2000 type scope? What's your opinion about that?

Dave, you do not need to turn off FFT on HMO, you can push the Time/Div knob then you will get to the upper time domain window, push again you can set gated FFT window size and possition, push third time goes back to the bottom spectrum window.

I've got the 64Xi model which also calls the Hanning for VonHann. It must be some LeCroy jargon. You can get used to it once you know what it is, but yeah, it is weird for the first time.

I do believe the FFT on the Rigol DS1054Z has had a bit of a firmware upgrade since this video was made or am I mistaken?

hey, Dave this is completely off topic but I watched your favorite movie last night, hmm wonder what it could be?

Dave, we're looking forward to a hover board tear down. They're around $200 USD on eBay nowadays. Thanks!

Indeed the Tek MSO4032 is quite slow too. I don't remember it being THAT slow, but I haven't used it in a while....

RE: MDO3104 being slow, you might have a really wide frequency bandwidth for an FFT? I just sold my BladeRF to a friend (wasn't using it), it had very nice FFT output.

I personally like the rohde&schwarz :-D

"It should be indicative" - Dave Jones 2017

I suspect one of the reasons the Rigols don't look very good is the poor phase noise on the sampling clocks (#683, #699). Would also explain the jumpiness on the 2202. Would be nice if Dave could do some tests to show how stable the sampling clocks are across different scopes. Even the DSA815's phase noise seems poor - note that the noise floor is only -55 dBc at low offsets, while the MDO3104 (in RF mode) had better than -80 dBc.

Hi Dave, if you had to build the ultimate lab, what stuff would you buy, (stuff that worth the money), what your lab dream would contain

Has anyone ever tested the Hantek DSO5202P FFT for comparison? Thanks.

You mentioned that a manufacturer would implement the DFT in different ways, but shouldn't the FFT of any method take the least processing power? I can only imagine it would be small variations on that particular theme.

Is the RS Pro 1100 series the same as the Gw Instek here?

At least the LeCroy got the name of the window right :) You know, the one named after Julius von Hann, and doesn't confuse it with the one named after Richard Hamming

the scope lags when u try to scoll it, and we understand, but whay if it just simply takes a snap shot of the current out put when u are scrolling?

18:55 - Rigol DS1004Z with Hz/Div of 250kHz is good, why change it to 25kHz and messy the graph?

Wondering how you get so many dso's !

Great Video still but the Rigol was not treated fairly! You needed to turn on "Deep Memory FFT" on the DS1054Z and the FFT will come to Life. This feature is on the next page in FFT mode. You most likely had it set to TRACE and only showed the data points that were displayed in the trace window. This upgrade to the firmware was released 1 year before your video. I know It's hard to know all the in's and out's of all the equipment!

Have you ever looked at Owon 'scopes ?

It would be nice to hear more on windowing in FFT and what's best for what i know i just use hanning for everything Also i must say i still hate the Z on the 1054Z ... it looks like someone took a marker to it

one of the performance comparison that I want to see is the maximum frequency that these oscilloscopes can do ... because some can go (as nyquist says) to 2.5Ghz... (I know whit atenuation) but I think that it is on propose limited ... ex:I used to have an agilent DSO-3202 that had best fft performance (in frequency range) than an DSO-1024a that I have now .. but unfortunately I didn't make any specific comparison (maby just impression ???) If you coud let us know the maximum allowed frequency they show) best regards from Brazil ...

What is the cost of those? New and used?

Im after a unit that will allow me to test the SWR of antennas up to 6Ghz. Can anyone recommend a unit that wont cost $10k?

My poor Rigol. :)

Dave, your comparisons of FFTs was very interesting. It would be great if you could compare the Tek 3104 with the GW Instek 4-channel MDO-2204EG (or the 2-channel MDO-2202EG) both of which have FFT of course, BUT, have a dedicated Spectrum Analyzer as well as a 2-channel AWG. In addition, both can do BODE plotting for FRA. And I don't know the street price on the Tek 3104 but I'll bet either Instek (MDO-2204EG or MDO-2202EG) will be less costly than the Tek. And, if you could demonstrat BODE plots with one of the Insteks that would be fantastic. I love your characterization of the RIGOLs "Dick & Balls" model... hilarious! I was laughing my balls off for at least 10,000 milliseconds, if not more!

I wish I had just one of those flat screen scopes. I have a Tektronix 465 that doesn’t work and a 475 that needs alignment.

Number of operations in an FFT is not linearly dependent on sample number. So 2 MegaSamples should take more than twice the time of a 1 MegaSamples...

WOW YOU KNOW OscilloscopeS.. I'D LIKE TO SEE SOME OPERATIONS NOW. Hold on ok, I'll be right back?

Does anyone know how well a siglent SDS1202X-E fares in this regard?

A 128k point FFT implemented in the usual fashion would require 17 passes over the data for 2.2 million operations. That said, you can parallelize it enormously. You could potentially run as many as 32k threads in parallel with no contention and little in the way of synchronization.

POST failure might be a bad CMOS battery failure?

The Rhode & Schwarz claims to use a "Hanning" window. There is no "Hanning" window. There is a Hann window and a Hamming window, but no "Hanning" window.

Brother you have heaven(my dream lab) on earth👌👌👌👌👌

I wonder if anyone really uses the scope FFT for something other than a quick test of the feature?

#EEVblog Frequency bin is exactly the right name!

yes Felix I agree but no body working in a repair workshop would ever use these functions

I have question: What happen if I measure 100MHZ With 50MHZ osliscop?

Hi from Ireland :)

can one of them play my mp3s?

Dave it is not fair . You are compairing a $2000+ Rohde & Schwarz oscilloscope to a $400 Rigol but anyway the video is good I have learnd from it.

what about siglent?

Where is siglent sds1202x 200MHZ osliscope?

voce nao pode doar um osciloscopio aqui pro Brasil ???