1.0 Review Outline
In part 1, I will first give a general introduction to the RTE1204 and take a detailed look at the physical and software user interface. I am continually learning and finding little quirks here and there, so I will be sure to edit and update part 1 as I post the next sections over the next two weeks. I waited a little while to post this, as my RTB2004 just arrived, and I wanted to add some side-by-side comparisons. It's obviously not fair to compare the performance of the two, but if figured that the interface and usability is fair game.
Table 1. Table of Contents for review
| Rhode and Schwarz RTE 1204 Review Section | Link |
|---|---|
| Part 0: Review Proposal | Rohde and Schwarz RTE1204 2GHz Oscilloscope Review: part 0 |
| Part 1: Introduction and User Interface | you are here |
| Part 2: Analog and FFT Functionality | to be added upon completion |
| Part 3: Mixed Signal Domain | to be added upon completion |
| Part 4: Conclusion and User Requests | to be added upon completion |
1.1 Introduction to the RTE1204
The RTE family of oscilloscopes from Rohde and Schwarz caters to the mid-range oscilloscope market, with up to 2GHz of analog bandwidth and a 5GS/s sampling rate per channel. The optional 16-channel, 400MHz mixed-signal and decode capability, powerful spectrum and power analysis, and a wide assortment of eletromagnetic/active probes make it clear that this scope is aimed at signal-integrity measurements in modern mixed/embedded systems. Indeed, I was first introduced to this scope when I was in the systems group at a large consumer electronics company, as we had a few in the lab. The RTE series is now a few years old, being released back in 2014, and I would not be surprised if R&S released a minor update to this line with a capacitive touch screen and button/knob interface that matched the RTB and higher-performance RTO families.
In their promotional material, R&S mentions the 16-bit mode vertical resolution at length, but to be clear, the actual ADC is an 8-bit device. The RTE "high definition" mode uses standard averaging/digital filtering techniques to trade off resolution with bandwidth, as with other scopes. The vertical enhancement vs filtering trade-off for the RTE is shown in the table below.
Table 2. High definition mode bandwidth vs enhanced vertical resolution
| Bandwidth | Vertical resolution (bits) |
|---|---|
| 10KHz-30MHz | 16 |
| 50MHz | 14 |
| 100MHz | 13 |
| 200MHz | 12 |
| 300MHz | 11 |
| 500MHz | 10 |
The RTE1204 has a waveform update rate of 1 million/second and optional increased memory depth up to 50Msamples on 4 channels, 100Msamples on 2 channels, or 200Msamples on 1 channel. There is also an optional 2-channel 100MHz, 500MS/s arbitrary waveform generator, capable of generating differential signals with 0.1 degree phase resolution and <200ps skew. This option also includes an 8-channel 40Mbit/s pattern generator. The unit that I have unfortunately does not have this option, but on paper it seems like a significant step above the 20MHz (Keysight) and 50MHz (Tektronix) arbitrary waveform generators available on comparable oscilloscopes. In my personal opinion, having a built-in function generator is not something I would opt for in this level of oscilloscope, which is intended to be used in a shared lab setting.
Table 3. Specifications for comparable oscilloscopes
Rohde & Schwarz RTE1204 | Keysight MSOX4154AMSOX4154A | Tektronix MSO5204BMSO5204B | Tektronix | |
|---|---|---|---|---|
| Max bandwidth | 2GHz | 1.5GHz | 2GHz | 2GHz |
Sampling rate on all channels | 5GS/s | 5GS/s | 5GS/s | 6.25GS/s |
Vertical resolution (true ADC bits) | 8 | 8 | 8 | 12 |
| Max effective bits in high-resolution mode | 16 | 12 | 11 | 16 |
| Waveform updates per second | 1,000,000 | 1,000,000 | 250,000 | 500,000 |
| Standard/max* record length per channel | 10M/50M | 4M | 25M/250M | 62.5M/125.5M |
| Approximate List price (including 16ch MSO) | $26,150 | $22,015 | $24,800 | $27,800 |
*with upgrade, not reflected in list price
In terms of the major specifications (bandwidth and sample rate), the Rohde and Schwarz RTE oscilloscope family is most easily compared to the Keysight MSOX4000-series and the Tektronix MSO 5000 series (and newer Tektronix 5-series). However, in terms of front-end noise and additional measurement features, the RTE series goes a bit beyond what is offered at least from Keysight here, as it is closer in some ways to their MSO6000x offerings. In particular, the RTE series allows for: eye diagram measurements, histograms, 4 advanced math signals, color grading, customized visualization, as well as a more comprehensive FFT measurement suite. Both Keysight 4000 and 6000 series offer a maximum of 4Mpts of sample memory, which seems oddly low.
HDO Oscilloscopes from Teledyne Lecroy are somewhat harder to directly compare to, given their interleaved-ADC architecture described here. Basically, they use more than one ADC with a clock and code offset to increase their effective number of bits. Their marketing department likes to make things confusing on their website by reporting aggregate sampling rate and making it seem like they use data converters with more than 8 bits. In any case, to match the performance of the RTE series, you have to go to the HDO9204, which has a list price of $25800, excluding the mixed-signal option.
As a comparison with slightly newer models: the MSRP of a R&S RTO2024 (4 channel 2GHz 20GS/s + 16ch MSO) is $29800, and that of a Keysight MSOS204A (4 Channel 2.5GHz 20GS/s + 16ch MSO) is $30800.
This class of scopes are clearly not marketed towards hobbyists, and the pricing of additional software/hardware options is no exception. Below is a quick summary from a few suppliers:
Table 4. Approximate cost for oscilloscope upgrades
| Option | R&S RTE option Cost | Equipvalent Keysight MSO4000 Option Cost (USD) | Equivalent Tektronix 5-series option cost (USD) |
|---|---|---|---|
| channel sample memory upgrade | $5300 -- 50M | N/A | $4990 -- 125M |
| 16-channel mixed signal option | $2950 | ~$2800 | $3600 |
| Power analysis option | $1700 | $1530 (but included in application bundle) | $2300 |
| Arbitrary waveform generator | * ` | $1020 -- 20MHz in application bundle) | $1250 -- 50MHz |
| Frequency/Spectrum Analysis | * ` | $1530 (but included in application bundle) | N/A |
| Eye diagram/Jitter analysis | N/A | N/A | $4720 |
| Individual trigger/decode options | $1550-1675 | ~$1530 | $1850 |
| Application bundle | * ` | $2750 | N/A |
*waiting for this quote.
`Note: the application bundle does not include this feature
I am still waiting for some clarification on the RTE1024 option pricing. I suspect that high-resolution mode and spectrum analysis are now offered by default on the RTE series, but they were formerly upgrades (I certainly hope this is the case). For the RTE1204 under review, the price -- as configured -- is in the neighborhood of $30000. It is clear that Keysight's application bundle offers the best value with respect to software upgrade cost. Tektronix does not seem to offer such a bundle for their 5-series, so trigger/decode options could likely become expensive very quickly.
1.2 Physical User Interface
The RTE1204 is shown below alongside the RTB2004. Being a higher-end scope, the build quality is noticeably better, but this feeling may be due in part to the significant heft of the RTE, weighing in at nearly 19 pounds. The front cover for the RTE is solid with a foam insert that conforms to the features of the oscilloscope and uses the rubber bumpers to mount to the scope. This is infinitely better than the cover for the RTB, which gets caught on a lip before attaching to the front panel, as others have noted. I have stopped using the RTB's cover for this reason, and I would not recommend it given its price. The carrying bags are also shown. Neither is anything special, but again the RTE is noticeably higher quality, as would be expected. It does offer both interior and exterior pockets for probes and the MSO components, whereas the RTB bag just has an interior compartment.
| {gallery:autoplay=false} RTE1204 and RTB2004 Physical Comparison |
|---|
RTE1204 and RTB2004 side by side |
With their covers |
Side profile |
Rear shot of the RTE1204 |
Carrying Bags |
Image Gallery 1. Physical Comparisons between RTE1204 and RTB2004
The front panel of the RTE1204 is shown in image gallery 2. The screen (1) on the RTE scopes is a 10.4" TFT touch screen with a resolution of 1024x728. Truth be told, it works well, and its matte finish does not attract finger prints like the RTB screen does, but it feels dated. TFT screens just do not have the same responsiveness that we have come to expect from capacitive touch screens, and they obviously do not allow for multi-touch gestures (not that an oscilloscope necessarily needs that, but they can be useful). Both the RTB and RTO have 10.1" 1280x800 capacitive touch screens for comparison.
| {gallery:autoplay=false} Rohde and Schwarz Front Panel Comparison |
|---|
RTE front panel |
RTB front panel |
RTO front panel |
Image Gallery 2. RTE, RTB, and RTO Front Panels (images from Rhode and Schwarz user manuals)
Upon first glance, the button placement is logical and intuitive. Those familiar with Keysight and Tektronix oscilloscopes will notice that each channel does not have its own dedicated vertical controls, which I do not mind, as the LED channel/color indication works very well. The knobs are all detented, and it is obvious that some oscilloscope users on the internet have very strong feelings about this, which I do not. They work well and are all press-able to change their mode/step size. My only complaint with the layout is that it is not efficient. There is a lot of real estate devoted to buttons on this oscilloscope (real estate that could be going towards a larger screen), and some of these buttons seem redundant or not very useful. For example:
- In the horizontal options, the "res rec len" and "horizontal" buttons bring up the same dialog box
- The vertical channels require a separate "signal off" button to turn off a trace, rather than just pressing the same channel button twice
- The escape button in the navigation does not actually escape from any dialog box. I did not find the navigation buttons, with the exception of the main knob, to be very useful -- this scope cannot be realistically operated without either the touch screen or a mouse, which is understandable but should be noted.
The next-generation RTO series front panel does have an updated look with colors that are more inline with the RTB series, and it does seem a little better in its use of space. However, the buttons are not fundamentally different. The RTB series does feel like a refinement, though. Here, the user can turn off channels without needing a dedicated button, and the button choice seems more useful (for example, it includes a force-trigger button that the RTE does not). Overall, I think R&S could benefit from a standardization of all aspects of their oscilloscope front panels. They seem to be moving in that direction, but there are still major differences between the RTO, RTM, RTB and especially the HMO (formerly Hameg) lines.
Given that the GUI of this scope is so customizable, it is a little disappointing that there are not more user-programmed options for hard keys. Only the print button has some degree of customization, allowing for different screenshot/report saving options. I would happily trade some buttons on the left hand side for macro-programmable buttons. The horizontal and vertical knobs can be switched from position to offset/ref point, and the navigation knob acceleration can be changed. It is nice that the LCD backlight intensity can be changed (unlike for the RTB), and the LED brightness can be turned fully off.
| {gallery:autoplay=false} Frontpanel software configurability |
|---|
LCD Screen and LED Brightness control |
Print button control |
Knob control |
Image Gallery 3. Front panel software controls
Booting the machine, as shown in the video below, takes approximately two minutes. You will also notice that the fans and relays get very loud during the self-test phase -- luckily it returns to a dull hum within another minute, and in all of my testing so far, I have never had it reach the same volume as it does while booting.
Video 1. Boot time and noise of the RTE1204.
1.3 Graphical User Interface
Having used a number of R&S instruments (mostly vector network analyzers), I always find it interesting to compare their interface with Keysight's. My opinion -- and feel free to correct me if I am wrong -- is that you get a lot more customizability with R&S. From which side your signal menu "bar" shows up on, to the font size, to the color of almost everything, you can control it. Of course, you can configure it to be totally overwhelming and user-unfriendly, so there is a bit of a learning curve. Keysight, by comparison, feels like a more controlled (and restrictive) experience. This is neither a good nor a bad thing -- it's just an observation.
I'll start with my favorite feature about this oscilloscope's interface: the "Smart Grid". It is a phenomenally different way of using an oscilloscope, and it lends itself extremely well to a touch screen. In a nutshell, "SmartGrid" allows you to drag and drop channels measurements, math functions, etc. into different sections of the screen. It's not just limited to quadrants -- you can stack up to 4 sub-windows in both x and y directions, and you can also sub-divide each window until the screen is jam-packed with information. Each tab can be annotated with a little menu that allows an easy way to close it, or you can alternatively "dock" your waveform back on the signal bar to be displayed later. It is possible to drag each window to individually control the size as well. See below for some screen-captured videos of these features.
Video 2. Demonstration of the "SmartGrid" -- moving traces/functions/FFTs and resizing the windows
I became so accustomed to this feature that I was very disappointed to find that my RTB scope only has a very primitive version of the Smart Grid (despite what the marketing material claims). In particular, the RTB scope does not allow a user to drag and drop different channels to different sub windows -- that would make for an impressive firmware update!
The two menu bars that are most accessible are those on the top and the bottom. The top toolbar is user-configurable, and this is what I use most often to get to the core features of this scope. To use any of the pinned actions, you simply click the icon and then click the trace that you want to apply the action to. The bottom toolbar mostly overlaps with hard-key functionality and it would be nice if you could hide it.
Screenshot 1. Top Tool bar customization options
Having the "show signal bar" paired to the top toolbar comes in very handy if you need to free up some real-estate when there are a lot of tabs open on the smart grid. You can switch this signal bar position to either the left or the right, control the transparency, or even enable "auto-hide" after a select-able amount of time. It is also easy to scroll through all of the available signals, measurements, and math functions.
Video 3. Signal Bar options on left/right and auto-hide
The next notable feature is the zoom. This option, when paired to the top toolbar, actually has 4 modes, selectable via a drag-down menu, as shown. Note-able differences are that standard zoom keeps the original waveform and settings in a top tab, and opens a separate zoomed tab. It is possible to create multiple tabs with different zoom locations of the same waveform and couple these zoomed regions either by position or by size. Adjusting the size (and to a lesser extent the position) of the zoomed regions can be somewhat difficult with the touch screen, and the navigation knob helps a lot. Hardware zoom changes the vertical resolution and time-base on the current window, and fingertip zoom just gives a snapshot of the signal below your finger.
Video 4. Normal Zoom
Video 5. Hardware Zoom
Video 6. Coupled Zoom
Video 7. Fingertip Zoom
With the SmartGrid, it is very nice to be able to display cursors on different tabs simultaneously. Luckily R&S thought of this, and I've shown how it is implemented in video 8. Unfortunately, you are limited to only two sets of cursors, so if you have all 4 (or more) channels up on separate tabs, you will have to pick and choose. It is also nice that you can pin the cursor measurement results to a separate area of the SmartGrid.
Video 8. Using separate cursors on different SmartGrid tabs
As you would expect, the same "pinning" can be done using both the quick and normal measurement functions. The quick measurements can be configured such that the user's the most desired measurements all come up with a single click. Normal measurements work the same way, and statistics are available with both, as shown in videos 9 and 10. In Video 10, you can see an issue that I came across frequently -- during a single trigger, the scope seems to display many waveforms overlapped for any trace that is not set as the active trigger. Fiddling with the horizontal position fixes this, but it gets a bit annoying, as that also resets the statistics.
Video 9. Quick measurements with statistics (also showing a single-trigger bug)
Video 10. Normal measurements
The last measurement I will cover in part one is the histogram (I'll save masks, search, FFT, etc. for later). You have the option of choosing up to 4 vertical or horizontal histograms. With multiple traces in a single window, you can only display one at a time, but again using the SmartGrid allows simultaneous histograms to be shown. Changing their relative size requires going into the menu -- you cannot simply drag it. I also found that occasionally the histogram icon in the top toolbar became grayed out for reasons I cannot explain. I could still go into the histogram menu and enable them via the bottom toolbar, but not the top.
Video 11. Histograms
I'll skip adding a bunch of additional videos (unless there are specific requests) about how to add labels to traces, change diagram names, etc. Suffice it to say that the user has a lot of control when it comes to customizing how it looks and how traces are displayed. You cannot draw on the screen as you can with the RTB -- it would be interesting to know if that feature has been added for the RTO scopes.
1.4 External Display
Normally this would not deserve its own section, but this is the one area where the RTE really falls short. For the life of me, I just could not get an external monitor functioning properly with the RTE1204. I tried different monitor sizes, resolutions, options within the R&S scope application and directly from the Windows control panel. Extending the display worked well enough if I wanted to use the external monitor for something else, but not with the scope application. Duplicating the screen or using only an external display resulted in odd behavior -- the oscilloscope application does not seem to like non-native resolutions. Using only the external display was the closest I got to "working", but then there is an issue with the mouse being offset from where you actually click in the application. Maybe I am doing something horribly wrong, but I would expect this to work without any major changes needed outside of the oscilloscope application.
Video 12. External Display Issues
1.5 Computer
Because this is a scope with an embedded Windows interface, the computer running the OS also deserves some attention. The specifications are shown below in screenshot 2.
Screenshot 2. Computer specifications
While its not very powerful by most modern computer standards, it seemed to have more than enough power to chug through whatever I could throw at it without any signs of slowing down. The oscilloscope application does indeed eat up a lot of power when running many SmartGrid screens at once with measurements and especially FFTs and spectrograms. In video 13, I show a case where I am using a significant amount of processing power to display two simultaneous FFTs and spectrograms.
Video 13. Performance when displaying many traces and math functions
That concludes part 1. As always, I will be paying attention to the comments, and I will also be actively updating this section (with edit dates and highlights) if I find errors or things to add. Expect part 2 soon. Thanks for reading,
James
Top Comments