Rohde & Schwarz Oscilloscopes - Questions/Comments? Let me know!

[LaurentR]

Crossposting from the RTB2004 thread a few issues that may not have been reported:
* Protocol decoding for Parallel and Parallel Clocked is only available using the Logic Channels (not the 4 analog channels). Is this limitation necessary?
* When selecting "Parallel" or "Parallel Clocked" in the "Protocol" menu then clicking on "Configuration"and "Bus Width", I haven't found a way to change the bus width using the touch screen or the web UI. It seems doable only through the "Analysis" physical knob.
* User Manual ver2 p115, there is a typo "Troggering on parallel buses is not possible."

[Rich@RohdeScopesUSA]

Crossposting from the RTB2004 thread a few issues that may not have been reported:
* Protocol decoding for Parallel and Parallel Clocked is only available using the Logic Channels (not the 4 analog channels). Is this limitation necessary?
* When selecting "Parallel" or "Parallel Clocked" in the "Protocol" menu then clicking on "Configuration"and "Bus Width", I haven't found a way to change the bus width using the touch screen or the web UI. It seems doable only through the "Analysis" physical knob.
* User Manual ver2 p115, there is a typo "Troggering on parallel buses is not possible."

Hi LaurentR - I've forwarded on your feedback to the team.  Thanks for submitting it!

-Rich

[ruairi]

Hi Rich,

An observation on R&S sales activity.  I bought and RTB2004 and love it. I'm now on the R&S mailing list and receiving the various Application Note / video link emails, this weeks was on measuring DC-DC converters using an RTO.  You are generating some excellent materials thank you.

I understand that the company is set up to sell mainly to corporate but forcing email sign in to get at the various resources is a real turn off, your competitor Keysight does not for example.  I have skipped several assets because of this.  Worse, twice now i have selected the no contact/no imminent purchase options and received follow up sales emails from Kristen anyhow.

I'm not an E.E. but not just a hobby user either, at last count I had 7 pieces of HP/Agilent/Keysight on the bench to my one R&S.  I'd love to make that more but the heavy handed stuff does not work in your favor.

[Rich@RohdeScopesUSA]

Hi Rich,

An observation on R&S sales activity.  I bought and RTB2004 and love it. I'm now on the R&S mailing list and receiving the various Application Note / video link emails, this weeks was on measuring DC-DC converters using an RTO.  You are generating some excellent materials thank you.

I understand that the company is set up to sell mainly to corporate but forcing email sign in to get at the various resources is a real turn off, your competitor Keysight does not for example.  I have skipped several assets because of this.  Worse, twice now i have selected the no contact/no imminent purchase options and received follow up sales emails from Kristen anyhow.

I'm not an E.E. but not just a hobby user either, at last count I had 7 pieces of HP/Agilent/Keysight on the bench to my one R&S.  I'd love to make that more but the heavy handed stuff does not work in your favor.

Hi ruairi - I really appreciate the feedback and understand your frustration (I've had similar frustrations on other websites).  It's a fine line we walk between supplying value-add content and asking for something in return (e.g. an email address).  I'll definitely pass this on to our marcom team to make sure we aren't erring too much on the "we need a sign-in for everything". 

And if you've opted out, you shouldn't be getting contacted.  If you want to PM me your contact info, I can make sure they update that so you aren't pinged again.

-Rich

[mikeselectricstuff]

The goodwill and publicity you get from making quality materials freely available will easily outweigh the badwill of hiding it away.
What do you actually gain from making it harder to access ? 


 

[nctnico]

The goodwill and publicity you get from making quality materials freely available will easily outweigh the badwill of hiding it away.
What do you actually gain from making it harder to access ?

I agree. Also the R&S website is a mess. If you click on a 'datasheet' link on an instrument page you are taken to a long list of seemingly random documents (some of the documents aren't even related to the instrument you where looking at). It is very hard to get a datasheet this way and usually I don't bother to look any further because it just takes too much time. If I click on a link which says 'datasheet' I want to see a PDF on my screen with a datasheet -nothing more nothing less-!

[Rich@RohdeScopesUSA]

The goodwill and publicity you get from making quality materials freely available will easily outweigh the badwill of hiding it away.
What do you actually gain from making it harder to access ?

I agree. Also the R&S website is a mess. If you click on a 'datasheet' link on an instrument page you are taken to a long list of seemingly random documents (some of the documents aren't even related to the instrument you where looking at). It is very hard to get a datasheet this way and usually I don't bother to look any further because it just takes too much time. If I click on a link which says 'datasheet' I want to see a PDF on my screen with a datasheet -nothing more nothing less-!

Totally agree   We are definitely working to fix it, but not as fast as I'd like.  It will get better.

-Rich

[ruairi]

The goodwill and publicity you get from making quality materials freely available will easily outweigh the badwill of hiding it away.
What do you actually gain from making it harder to access ?

This is the crux of it.  The email capture paradigm had it's day maybe 10 years ago and these days just serves to annoy, I have tried really hard to make companies I work with see this. 

Rich - thanks for the quick reply.  Every freely available resource is an opportunity to highlight unique features on your products and to normalize your brand in the eyes of new potential clients. At very least R&S need to consider how they disseminate materials aimed at beginners and students.  Emails offering sales calls are not the right approach for the next generation.

Edit - One easy step for now is to properly identify people clicking through who are already on the email mailing list.  If I click a custom link in an email then you know I'm already in your system and can allow me access to the content without forcing sign up or sign in.

[fonograph]

1. What type of filter does RTE use in its hardware anti aliasing front end? Is it butterworth or gaussian?
2. What order is the anti aliasing hardware filter? Is it 4 order? 8 order??
3. What is the atenuation at nyquist frequency?
4. What filter type is the so called decimator hi res mode?
5. What filter type is the optional 16 bit hi res mode? They say its different from the non-option one,but I cant tell what type is either of them.Hi res is usualy boxcar/rectangular window or gaussian,I want to know what type are both hi res modes.

6. What filter type is the 200Mhz and 20Mhz hardware filter?
7. What order is the 200Mhz and 20Mhz hardware filter?
8. What type is the software bandwidth filter? I mean the filter that exist to block the user from using full bandwidth until he pays for upgrade license.
9. What order is the software bandwidth filter?
10. Does it use any kind of DSP correcting filters? For example phase correcting allpass filters or any kind of phase,group delay or frequency filter on top of any of the filters I already mentioned in previous questions?


I have experience that when I unload avalanche of questions on someone,they are unlikely to answer them all or answer at all.I am considering buying RTE,I absolutely need every single of these questions properly and truthfully answered so I know what is the combined phase and group delay response at every particular software bandwidth and hi res setting resuling from all the filters in the scope.

[Rich@RohdeScopesUSA]

1. What type of filter does RTE use in its hardware anti aliasing front end? Is it butterworth or gaussian?
2. What order is the anti aliasing hardware filter? Is it 4 order? 8 order??
3. What is the atenuation at nyquist frequency?
4. What filter type is the so called decimator hi res mode?
5. What filter type is the optional 16 bit hi res mode? They say its different from the non-option one,but I cant tell what type is either of them.Hi res is usualy boxcar/rectangular window or gaussian,I want to know what type are both hi res modes.

6. What filter type is the 200Mhz and 20Mhz hardware filter?
7. What order is the 200Mhz and 20Mhz hardware filter?
8. What type is the software bandwidth filter? I mean the filter that exist to block the user from using full bandwidth until he pays for upgrade license.
9. What order is the software bandwidth filter?
10. Does it use any kind of DSP correcting filters? For example phase correcting allpass filters or any kind of phase,group delay or frequency filter on top of any of the filters I already mentioned in previous questions?


I have experience that when I unload avalanche of questions on someone,they are unlikely to answer them all or answer at all.I am considering buying RTE,I absolutely need every single of these questions properly and truthfully answered so I know what is the combined phase and group delay response at every particular software bandwidth and hi res setting resuling from all the filters in the scope.

Hi fonograph - thanks for the questions - I'll get answers for you on all of them as soon as possible and post them back up.  Is there a hard deadline of when you need the response by?

-Rich

[fonograph]

No,I dont need the answers fast,take your time,just please give me the answers.

[Rich@RohdeScopesUSA]

1. What type of filter does RTE use in its hardware anti aliasing front end? Is it butterworth or gaussian?
2. What order is the anti aliasing hardware filter? Is it 4 order? 8 order??
3. What is the atenuation at nyquist frequency?
4. What filter type is the so called decimator hi res mode?
5. What filter type is the optional 16 bit hi res mode? They say its different from the non-option one,but I cant tell what type is either of them.Hi res is usualy boxcar/rectangular window or gaussian,I want to know what type are both hi res modes.

6. What filter type is the 200Mhz and 20Mhz hardware filter?
7. What order is the 200Mhz and 20Mhz hardware filter?
8. What type is the software bandwidth filter? I mean the filter that exist to block the user from using full bandwidth until he pays for upgrade license.
9. What order is the software bandwidth filter?
10. Does it use any kind of DSP correcting filters? For example phase correcting allpass filters or any kind of phase,group delay or frequency filter on top of any of the filters I already mentioned in previous questions?


I have experience that when I unload avalanche of questions on someone,they are unlikely to answer them all or answer at all.I am considering buying RTE,I absolutely need every single of these questions properly and truthfully answered so I know what is the combined phase and group delay response at every particular software bandwidth and hi res setting resuling from all the filters in the scope.

Hi fonograph - sorry it took a bit of time, but here are answers to your questions - please let me know if you need more details.

-Rich

***************************************
1. What type of filter does RTE use in its hardware anti aliasing front end? Is it butterworth or gaussian?
R&S: See 2.

2. What order is the anti aliasing hardware filter? Is it 4 order? 8 order??
R&S:  The anti-alias filter is a 2nd order Bessel filter. (Bessel filter is that type of linear filter with a maximally flat group/phase delay). Up to 1 GHz the phase is almost perfectly linear (Deviation from linear phase +/-1 degree). Up to 1.5 GHz it's within +/-7 degrees.

3. What is the atenuation at nyquist frequency?
R&S: The attenuation at nyquist is -20dB

4. What filter type is the so called decimator hi res mode?
R&S: See 5.

5. What filter type is the optional 16 bit hi res mode? They say its different from the non-option one,but I cant tell what type is either of them.Hi res is usualy boxcar/rectangular window or gaussian,I want to know what type are both hi res modes.
R&S: The HD mode you refer to is now standard on the RTE1000.  Different filter types are used depending on the bandwidth of the filters: For high bandwidths, a moving average filter is used. For lower bandwidths, FIR filtering is realized with symmetrical filter coefficients. The roll-off for the FIR filter is Gaussian. 

6. What filter type is the 200Mhz and 20Mhz hardware filter?
R&S: 2nd order Bessel filter. (Bessel filter is that type of linear filter with a maximally flat group/phase delay)..

7. What order is the 200Mhz and 20Mhz hardware filter?
R&S: 2nd order Bessel filter. (Bessel filter is that type of linear filter with a maximally flat group/phase delay).

8. What type is the software bandwidth filter? I mean the filter that exist to block the user from using full bandwidth until he pays for upgrade license.
R&S: See 9

9. What order is the software bandwidth filter?
R&S: This filter is also an FIR filter. The roll-off depends on the bandwidth of the instrument.

10. Does it use any kind of DSP correcting filters? For example phase correcting allpass filters or any kind of phase,group delay or frequency filter on top of any of the filters I already mentioned in previous questions?
R&S: The RTE has some symmetrical linear-phase correction FIR filter for some slight equalization of the magnitude of the frequency response.

***************************************

[fonograph]

Wow! Thanks Rich! I was thinking you probably wont answer everything,but you did!

I would like if you could provide same answers but for RTO,both the old and new one.You dont to repeat everything,just mention those questions whose answer is different from the one you gave me now for RTE.

Also,I want to know what are all other differences between the new and old RTO.The newer have bigger screen and different front pannel and knobs,but what else is differet? I think the FFT runs faster on the new one?

edit: I would like to separate this further into 4 categories total.The new and old RTO and  10GS/s and 20GS/s models.I have read that old RTO 10 GS/s had gaussian anti aliasing hardware filter,and the 20 GS/s had butterworth aka maximaly flat filter.The new one 20 GS/s now goes up to 6 GHz instead of 4 GHz for old one,so I am not sure what changed,I suspect the filter changed for steeper one or you started using fir filter compensation to make it flat close to nyquist.

[Rich@RohdeScopesUSA]

Wow! Thanks Rich! I was thinking you probably wont answer everything,but you did!

I would like if you could provide same answers but for RTO,both the old and new one.You dont to repeat everything,just mention those questions whose answer is different from the one you gave me now for RTE.

Also,I want to know what are all other differences between the new and old RTO.The newer have bigger screen and different front pannel and knobs,but what else is differet? I think the FFT runs faster on the new one?

edit: I would like to separate this further into 4 categories total.The new and old RTO and  10GS/s and 20GS/s models.I have read that old RTO 10 GS/s had gaussian anti aliasing hardware filter,and the 20 GS/s had butterworth aka maximaly flat filter.The new one 20 GS/s now goes up to 6 GHz instead of 4 GHz for old one,so I am not sure what changed,I suspect the filter changed for steeper one or you started using fir filter compensation to make it flat close to nyquist.

Hi fonograph,

I'll get the details and come back to you (I'm assuming you don't care about the obvious things like the RTO2000 supports up to 2GSa of memory versus the RTO1000 - you are mainly looking at frontend and filtering differences - is that correct?).

-Rich

[fonograph]

I am interested in other things too,but the thing is,if its in datasheets,then I can look that up myself without bothering you,but these filter details arent in datasheet.So if there is any significant differences then tell me,I am especialy interested on things that arent in datasheet.For example the new RTO might have faster cpu and run faster,or new fft asic or something and if its not mentioned in datasheet I would never know.

[nctnico]

This kind of info is never in test equipment datasheets. Sometimes the user manual has more information but in many cases you are expected to use more generic literature to research how filtering and signal reconstruction is done.

[rhb]

As I read the user manual, the RTB2004 will do an FFT for the entire record for the length currently set which would be 20 Mpts for two channels from different groups or 10 Mpts for 4 channels.

Is that correct?  The record lengths are not powers of 2, so does it do a prime factor mixed radix FFT, round up with zero padding or round down?

[rhb]

As I read the user manual, the RTB2004 will do an FFT for the entire record for the length currently set which would be 20 Mpts for two channels from different groups or 10 Mpts for 4 channels.

Is that correct?  The record lengths are not powers of 2, so does it do a prime factor mixed radix FFT, round up with zero padding or round down?

[nctnico]

As I read the user manual, the RTB2004 will do an FFT for the entire record for the length currently set which would be 20 Mpts for two channels from different groups or 10 Mpts for 4 channels.

Is that correct?

Nope. The same datasheet says 128kpts max.

[casinada]

New firmware was promised for October. May be Rich can give us an update. 

[Rich@RohdeScopesUSA]

I am interested in other things too,but the thing is,if its in datasheets,then I can look that up myself without bothering you,but these filter details arent in datasheet.So if there is any significant differences then tell me,I am especialy interested on things that arent in datasheet.For example the new RTO might have faster cpu and run faster,or new fft asic or something and if its not mentioned in datasheet I would never know.

Got it - let me see what I can find out. 

-Rich

[Rich@RohdeScopesUSA]

As I read the user manual, the RTB2004 will do an FFT for the entire record for the length currently set which would be 20 Mpts for two channels from different groups or 10 Mpts for 4 channels.

Is that correct?

Nope. The same datasheet says 128kpts max.

Correct.

-Rich

[Rich@RohdeScopesUSA]

New firmware was promised for October. May be Rich can give us an update. 

Should be out shortly!  If not this week, next.

-Rich

[mike_b_]

Hi Rich,

First of all, thank you for spending time answering so many questions.

I received my new RTB2004 a few weeks ago and I think it's really amazing.  I did notice an oddity though that I wanted to ask about.

I'm noticing that on certain signals at certain timesteps, the rendered waveform appears to dramatically change -- please see the attached images.  In this case, at 1.9ms the signal is as it should be, but at 2ms it changes dramatically.  I tested it further by manually entering in time steps, and I can get really close to the 2ms point with the correct result still produced -- 1.999ms and 2.001ms both produce the correct waveform, for instance.  Do you have any idea what's going on here?  Apologies if I'm making an obvious mistake -- I haven't used scopes as sophisticated as this before.

It appears to be purely a rendering issue, rather than an aquisition issue -- if I one-shot the trigger, the artifact still appears at 2ms, but disappears when paused if I change the time step.  It also disappears if I mess around with the memory depth.

Anyway sorry for the rambling question.  Apart from this weird issue I'm having a great time with the scope!

[Rich@RohdeScopesUSA]

Hi Rich,

First of all, thank you for spending time answering so many questions.

I received my new RTB2004 a few weeks ago and I think it's really amazing.  I did notice an oddity though that I wanted to ask about.

I'm noticing that on certain signals at certain timesteps, the rendered waveform appears to dramatically change -- please see the attached images.  In this case, at 1.9ms the signal is as it should be, but at 2ms it changes dramatically.  I tested it further by manually entering in time steps, and I can get really close to the 2ms point with the correct result still produced -- 1.999ms and 2.001ms both produce the correct waveform, for instance.  Do you have any idea what's going on here?  Apologies if I'm making an obvious mistake -- I haven't used scopes as sophisticated as this before.

It appears to be purely a rendering issue, rather than an aquisition issue -- if I one-shot the trigger, the artifact still appears at 2ms, but disappears when paused if I change the time step.  It also disappears if I mess around with the memory depth.

Anyway sorry for the rambling question.  Apart from this weird issue I'm having a great time with the scope!

Hi mike_b - first, congrats on the new scope!

Second, I believe the issue you are describing is a known bug that is fixed in the upcoming release.  Please let me know if you still see it after the update (should be out later this week or next).

-Rich