Recommendation Request - NEW Rigol DS1054Z or USED Tektronix 2467BHD

[Howardlong]

Just for fun?  Well, one _could_ use scope settings that give the scope a chance to perform, I suppose. But that might be cheating.....   

Source: HP8640B
Scope: DS1054z "unlocked" to 100MHz bw

In fact, I tried a number of settings over the period of about fifteen minutes to get a reasonable display but failed, including number of points, intensity, hold off etc etc. What was your magic sauce?

[alsetalokin4017]

Just for fun?  Well, one _could_ use scope settings that give the scope a chance to perform, I suppose. But that might be cheating.....   

Source: HP8640B
Scope: DS1054z "unlocked" to 100MHz bw

In fact, I tried a number of settings over the period of about fifteen minutes to get a reasonable display but failed, including number of points, intensity, hold off etc etc. What was your magic sauce?

Dots, anti-aliasing, intensity and persistence, mostly.

And I'm even (mostly) in the "analog" camp, too!

[G0HZU]

Just for fun?  Well, one _could_ use scope settings that give the scope a chance to perform, I suppose. But that might be cheating.....   

Source: HP8640B
Scope: DS1054z "unlocked" to 100MHz bw

In fact, I tried a number of settings over the period of about fifteen minutes to get a reasonable display but failed, including number of points, intensity, hold off etc etc. What was your magic sauce?

I can remember that Dave managed to get a pretty reasonable 'graded' display from the 1054 in his youtube review. Even my old TDS2012 looks better on an AM waveform than your previous attempt with the 1054 and my TDS2012 doesn't have intensity grading 

I suspect that the Tek MDO 3000 is capable of a lot better too. At work we have a lot of the big old Tek MSO/DPO 4000 scopes and with a fair bit of menu bashing you can get a fairly acceptable graded display. Not as nice as an old school analogue scope but I suspect that the difference is of limited benefit in terms of extra information anyway. But to someone of my generation the graded display does look a bit lame compared to a decent CRO.

[vk6zgo]

Also, I guess my other scope (WaveRunner 64Xi, unfortunately out of order at the moment) would have been a better choice for that scenario, as it has a mode called WaveStream which much better reflects the behavior of an analog scope:



(the video shows a WaveRunner Xi)

Either the Waverunner is "making heavy weather"  resolving the burst & horizontal sync pulse,or the originator of this video picked a particularly poor example of a video signal.
A clean burst should have a well defined envelope shape,& there shouldn't be that much sync tip noise,to say nothing of the rounding of the sync pulse leading edge & the overshoot preceding the falling edge.

In any case,a reasonably modern DSO should not have problems resolving a signal with a maximum frequency component of 5MHz,at a setting of 10 us/div.
Where many of them had problems was when the user attempted to display the same signal at field rate.or as is the more common test,tried to look at both the odd & even fields,requiring an overall time of 40ms.

My feeling about "intensity grading" is that it arose from a fundamental misunderstanding of people's objections to earlier DSOs---something along the lines of:-
"The silly old b----s won't be happy till we make it look like an analog 'scope"

What they didn't (or didn't want to) understand was that  we would have been happy with a "leaky fountain pen" display  attached to an instrument that wouldn't "fail at every hurdle" during.everyday tests.

[TheSteve]

100 MHz AM 1 kHz @ 50 %, then hit the auto button on my "unlocked" 1054Z.

Second pic with the intensity turned down.

[vk6zgo]

100 MHz AM 1 kHz @ 50 %, then hit the auto button on my "unlocked" 1054Z.

Second pic with the intensity turned down.

As I have already pointed out,this display is not a lot of use in determining any important information about the characteristics of the AM signal.
Neither does it say anything useful about the performance of the DSO.

[TheSteve]

100 MHz AM 1 kHz @ 50 %, then hit the auto button on my "unlocked" 1054Z.

Second pic with the intensity turned down.

As I have already pointed out,this display is not a lot of use in determining any important information about the characteristics of the AM signal.
Neither does it say anything useful about the performance of the DSO.

Fair enough - you can see AM depth and amplitude but that is about it. Adjusting the time base will let you see the modulation frequency easy enough. If I really need details of an AM signal I generally use my spectrum analyzer which has a modulation analyzer built in.

[vk6zgo]

"you can see AM depth and amplitude "---can you,though?

I'd have to play around with it to see how viable a method it is.

The conventional modulation rate triggered display has well established formulas,enabling quick determination of modulation percentage.
Even it gives way to the "trapezoid" pattern method for precision,however.

[Fungus]

Just for fun?  Well, one _could_ use scope settings that give the scope a chance to perform, I suppose. But that might be cheating.....   

Heresy! You'll burn in Analog hell for posting those blasphemous images.

[mtchastain]

Hi All,
Not to interrupt this lively discussion (definitely a bit over my head now) but I wanted to thank everyone for the recommendations regarding my question. Based on all the feedback, I will be planning on purchasing the Rigol scope.

Thanks again everyone!

-Matt

[SteveLy]

Well, just as a teaser - could somebody post a screen shot from the Rigol DS1054Z (or a similar DSO scope) of a 100Mhz signal with 50% AM modulation at 1kHz.

Most unfair since the DS1054Z is a 50MHz scope. And yours is not a screenshot. Analog scopes don't do screenshots. I bet with the right settings on the scope and on the camera taking the photo you could get something very similar out of a DS1054Z (or DS1104Z that's actually 100MHz capable).

@mtchastain Great choice! 

[Howardlong]

Just for fun?  Well, one _could_ use scope settings that give the scope a chance to perform, I suppose. But that might be cheating.....   

Source: HP8640B
Scope: DS1054z "unlocked" to 100MHz bw

In fact, I tried a number of settings over the period of about fifteen minutes to get a reasonable display but failed, including number of points, intensity, hold off etc etc. What was your magic sauce?

I can remember that Dave managed to get a pretty reasonable 'graded' display from the 1054 in his youtube review. Even my old TDS2012 looks better on an AM waveform than your previous attempt with the 1054 and my TDS2012 doesn't have intensity grading 

I suspect that the Tek MDO 3000 is capable of a lot better too. At work we have a lot of the big old Tek MSO/DPO 4000 scopes and with a fair bit of menu bashing you can get a fairly acceptable graded display. Not as nice as an old school analogue scope but I suspect that the difference is of limited benefit in terms of extra information anyway. But to someone of my generation the graded display does look a bit lame compared to a decent CRO.

The typical Dave method is with 1MHz carrier and 1kHz modulation, so is far less "stressful": there is little problem getting a reasonable display with this on a DSO with intensity gradient and reasonable deep memory, pretty much the only thing you need to fiddle with is the hold off just as you would in an analogue scope.

Using 100MHz carrier means the scope will have to be able to trigger accurately at nanosecond or less resolution while still being able to display at 1ms/div.

[vk6zgo]

Well, just as a teaser - could somebody post a screen shot from the Rigol DS1054Z (or a similar DSO scope) of a 100Mhz signal with 50% AM modulation at 1kHz.

Most unfair since the DS1054Z is a 50MHz scope. And yours is not a screenshot. Analog scopes don't do screenshots. I bet with the right settings on the scope and on the camera taking the photo you could get something very similar out of a DS1054Z (or DS1104Z that's actually 100MHz capable).

@mtchastain Great choice! 

Quite apart from the fact that he never claimed it as such,it is in fact a screenshot.
The term predated devices which could save their displays to another device by many decades.

Are you implying that the artifacts present on the display are from the transfer process,& were not visible on the original DSO screen?

That "puts the cat amongst the pigeons" for all such postings of a DSO display,unless they are produced photographically.

What is a bit unfair is the high carrier frequency chosen,plus the number of modulation cycles displayed.
That is certainly a savage test for a 50MHz,or even a 100MHz DSO.

A 50MHz analog would just need the signal level increased to compensate for being some dBs down on the response slope.

[BravoV]

I own a comparable Tek 2465B and 2 sub 100Mhz DSOs, my POV is simple ...

Rigol DS1054Z -> Cover by warranty.

Tek 2467BHD -> Full of risk, and if you're running of of luck, it may be dead at the 2nd times you powering it up. And pray really hard that its not those unobtainium hybrid IC that is toasted. 

Also you will need "another" scope to aid the troubleshooting of that dead Tek analog scope if that happened.

Maybe its just me, its so obvious and clear, and no, it is not even about analog vs dso, its a decision to choose on a working and worry free scope that you need it to help your work 1st.

[Howardlong]

Just for fun?  Well, one _could_ use scope settings that give the scope a chance to perform, I suppose. But that might be cheating.....   

Source: HP8640B
Scope: DS1054z "unlocked" to 100MHz bw

In fact, I tried a number of settings over the period of about fifteen minutes to get a reasonable display but failed, including number of points, intensity, hold off etc etc. What was your magic sauce?

Dots, anti-aliasing, intensity and persistence, mostly.

And I'm even (mostly) in the "analog" camp, too!

Hmm, not much luck I'm afraid at 100MHz, lots of beating, but at 101MHz, I got this though (dots definitely at these high carrier frequencies BTW)...



A bit more old school, but one of my favourite scopes, an Agilent 54642D made it easy, no fiddling other than hold off and setting to dots:

[G0HZU]

The typical Dave method is with 1MHz carrier and 1kHz modulation, so is far less "stressful": there is little problem getting a reasonable display with this on a DSO with intensity gradient and reasonable deep memory, pretty much the only thing you need to fiddle with is the hold off just as you would in an analogue scope.

Using 100MHz carrier means the scope will have to be able to trigger accurately at nanosecond or less resolution while still being able to display at 1ms/div.

Traditionally, you are supposed to trigger the scope using the baseband modulation signal rather than try and trigger from the modulated waveform. I can feed >200MHz into my 100MHz TDS2012 and instantly get a stable display by using external trigger from the 1kHz modulation signal. Most sig gens have a modulation out connector. Use this to trigger the scope

[G0HZU]

Maybe its just me, its so obvious and clear, and no, it is not even about analog vs dso, its a decision to choose on a working and worry free scope that you need it to help your work 1st.

I wouldn't have a Tek 2465 here anyway. I would buy the 1054 and then buy something cheap like my old Tek 465 to use for certain traditional tests.
I'm one of the few that doesn't rate the Tek 2465 as a good choice for a basic analogue scope. To me it is too big, the trace quality is fairly poor, the UI is fiddly and it has too many distracting lamp indicators on the front panel. So I can't tolerate having one of these things in my face. I don't like the look of these scopes at all.

[Wuerstchenhund]

Just for fun?  Well, one _could_ use scope settings that give the scope a chance to perform, I suppose. But that might be cheating.....   

Yes, I know  I should really have paid more attention  Me culpa!

Anyways, I have provisionally assembled my LeCroy WaveRunner 64Xi and found a chance to give it a try there, this time with the scope set a 1ms/div 

I'll post the pictures later.

[Howardlong]

The typical Dave method is with 1MHz carrier and 1kHz modulation, so is far less "stressful": there is little problem getting a reasonable display with this on a DSO with intensity gradient and reasonable deep memory, pretty much the only thing you need to fiddle with is the hold off just as you would in an analogue scope.

Using 100MHz carrier means the scope will have to be able to trigger accurately at nanosecond or less resolution while still being able to display at 1ms/div.

Traditionally, you are supposed to trigger the scope using the baseband modulation signal rather than try and trigger from the modulated waveform. I can feed >200MHz into my 100MHz TDS2012 and instantly get a stable display by using external trigger from the 1kHz modulation signal. Most sig gens have a modulation out connector. Use this to trigger the scope

That was indeed one of the tests I tried yesterday, it didn't make much difference, and, as it halved the sample rate on the Rigol by using a second channel (no ext trigger, so needed to use a spare channel and even if switched off, if you use the channel for triggering the ADC appeared to be used) I went back to single channel.

[Wuerstchenhund]

Either the Waverunner is "making heavy weather"  resolving the burst & horizontal sync pulse,or the originator of this video picked a particularly poor example of a video signal.

I think the idea was to present looking at a poor video signal, but yes the video isn't great.

There's another one:




At the end of the day the idea of WaveStream was to provide a mode that looks and feels "analog" like. Nothing more. I can't say I've ever felt the need to use it, though.

[EV]

Rigol DS2202

[Rupunzell]

Gigatronics 1018 generator, Tektronix 7104, 7A29, 7A24, 7B10, 7B15, Krohn Hite 1000 FG, hp 3326A synthesizer, Vari-L mixer.
Have a Tek 2467B, it is used only when a portable is required. Sits in storage most of the time. Tek 7000 simply has better performance, ergonomics and MUCH better configurability due to plug-ins.


Balanced mixer, 1.5Ghz carrier, 1Khz sine modulation, trigger on modulated signal.


Balanced mixer, 1.5Ghz carrier, 1.25Mhz triangle modulation, trigger on modulated signal.


Gigatronics 1018 set to AM, 1.5Ghz carrier, 30Khz modulation. Trigger on modulated signal:


Tek 7104 has zero problems triggering on a modulated signal at 1.5 Ghz carrier.


Using both time bases, top is the 1.5Ghz carrier, bottom is the 1Khz sine wave carrier:


2 Ghz sine wave:


Another way to measure this:
Gigatronics 1018 to 1.5Ghz carrier, 30Khz sine AM mod, hp 8566B:


Gigatronics 1018 to 18Ghz carrier, 30Khz sine AM mod, hp 8566B:





Bernice

[Rupunzell]

There is also Mr. Gibbs to consider:
https://www.eevblog.com/forum/testgear/my-first-oscilloscope/75/

Really comes down to knowing test gear limitations, how to get the best of them and their limitations. While there are user preferences, that is a matter of individual choice in the same way as food preferences. Still, technical limitations apply.


Bernice

[Wuerstchenhund]

Most unfair since the DS1054Z is a 50MHz scope. And yours is not a screenshot. Analog scopes don't do screenshots.

Actually, that is exactly where the term 'screenshot' comes from - taking a picture of the image on an analog scope's CRT with a special photographic camera.

BTW, what modern scopes like the DS1054z do is not a 'screenshot', it's actually a 'screen dump' because they don't take a 'shot  of the screen but dump the content of the video memory into a file. It's just because people were more familiar with the term 'screenshot' so they still use the term for DSOs.

[Wuerstchenhund]

Next try, this time I did even pay attention to the timebase settings 

Again, source is a R&S CRTU-RU at 100MHz modulated at 1kHz AM 50%. The scope is a provisionally assembled LeCroy WaveRunner 64Xi, and since the CRTU-RU has no Mod out it's triggered from the input signal.

These screenshots show the signal in Persistence (intensity graded) mode at 500MS/s and 1GS/s:



https://www.eevblog.com/forum/testgear/recommendation-request-new-rigol-ds1054z-or-used-tektronix-2467bhd/?action=dlattach;attach=180776;image


And this is what it looks like in Normal mode:

At 2GSa/s:




And at 500MSa/s:




Anyways, as it was said above that's a pretty synthetic test for a digital scope which is unlikely to matter in a practical sense.