RoadTest: Agilent MSOX2024A with a Development Kit
Author: tekmeister
Creation date:
Evaluation Type: Independent Products
Did you receive all parts the manufacturer stated would be included in the package?: True
What other parts do you consider comparable to this product?: Agilent MSOX-3000, Tektronix MSO2000B
What were the biggest problems encountered?: null
Detailed Review:
A bit about myself first:
I'm a university graduate with a Bachelor's Degree in Engineering (Electronic and Electrical). I've been working for the past 10 years in the embedded world. Currently I'm the primary firmware engineer for a company which designs and manufactures touchscreens. My firmware has shipped on 4 million units worldwide.
Oscilloscopes are an integral part of my professional toolbox and are used daily. They help me verify the firmware/hardware I'm working on is working as expected. Probably the only equipment I use more frequently would be the JTAG programmer/debugger.
In this review I don't intend to cover every single feature on the oscilloscope, but rather to approach it from a real-world perspective. I will examine how the unit performs with everyday use.
As this is my first RoadTest review, I appreciate any feedback. If there are any features you would like me to expand upon, let me know. You can leave a comment below, or send me a private message.
When it comes to oscilloscopes, 2 major brands come to my mind: Agilent and Tektronix. These companies (along with Lecroy) have historically been the leading forces for test equipment.
Quality test equipment generally carries a price premium, but it's mostly a case of getting what you pay for. Accuracy is paramount - you need to know you can trust what the gear says - but other factors also come into play. For instance, the user interface, the output noise from the fans, and the documentation can also make or break a good user experience.
I've had the displeasure of dealing with low-end budget-brand scopes in the past. I've also used some high-end big-brand scopes that were similarly frustrating. This tends to be mostly due to poor user interface, under-par performance, or ill-considered design.
My main scope up to now has been a Tektronix TDS2014B, 4-channel 100MHz. It's a great little unit, but in many respects outdated. It comes from the era of DSOs with very small memory, which makes capturing glitches difficult and is frustrating when you want to zoom into part of the capture. There's no digital serial decoding and limited USB support. For measurements that require higher bandwidth or more memory, I have access at work to a Tektronix DPO7254. This is essentially a full-blown PC built into a box.
I also use a Saleae Logic which to capture and validate digital comms and a Fluke multimeter which comes in handy for quick current/voltage measurements. If needed I have access to a Rigol arbitrary waveform generator.
The MSOX2024A promises to replace all this equipment in a single unit. Sounds great in theory, but how does it work in practice? In order to find out, I brought the MSOX2024A into the office and put it to the test.
The MSOX2024A is the top model in Agilent's entry-level MSOX2000 series of oscilloscopes. It features 200MHz bandwidth with 4 analogue inputs, 8 digital inputs, and optional add-ons for integrated waveform generator, serial protocol decoding and digital voltmeter. Agilent also offer a 5-year warranty as standard.
On the face of it, these specifications are perfect for my day-to-day needs. Mostly I'm dealing with micro-controllers with a system clock of about 48-180MHz, and any external signals are running at much slower clock rates. It's rare that I need to monitor more than 4 analog signals simultaneously.
There is no support for 50Ohm inputs (only 1MOhm), which generally isn't a problem unless you're dealing with high frequencies anyway. There's also no automatic probe detection.
The MSOX2024A is promoted as 5 instruments in one:
Of course, much of the functionality is only enabled after purchasing separate software licences. It's a business model which is becoming increasingly common amongst test-gear and a way of lowering the entry price and allowing users to upgrade as they need features.
Usually my element14 orders ship from their local warehouse. In this case, the unit was shipped from the other side of the world. It took a fair while for it to arrive, but eventually turned up. The box was a little shaken:
Any hoarders who like to keep the packaging will be disappointed that the unit is only single-boxed. Some other test gear I recently received was shipped double-boxed, so while the outer box was showing signs of wear and tear after shipping, there was an inner box that was in pristine condition. It was a nice touch, perhaps something for Agilent to consider.
Besides the scope itself, the box contained 4 N2863B 300 MHz probes, a N6459-60001 8-channel logic probe set, a CD containing documentation and the scope calibration documentation.
As part of the roadtest, Agilent provided me with licences for some of the upgrade options, which will be mentioned later in this review. The STM32 F4 discovery board was also included in the package, but this will be reviewed separately.
The MSOX2024A feels solid, and is slightly heavier than it looks (it's ~3.8kg). It's larger than the Tektronix TDS2014B but not so large as to be cumbersome.
Boot time is 36 seconds - about normal for this sort of equipment and comparable with the TDS2014B. While the unit is starting up, it proudly displays its splash screen. The sticker on the back of the scope tells me it's running Windows Embedded CE 6.0.
The unit runs extremely quietly - I can't hear it over the fan from my laptop - and is cool to the touch. I check the firmware info (Help - About Oscilloscope), it states version 2.35. According to the Agilent website, this is the latest version, dated June 2013.
Right from the outset, the scope looks and feels like a professional piece of equipment. I really like the layout of the front panel - it is well designed. Controls are clearly labelled and in logical positions. The "Default Setup" and "Auto Scale" buttons are handily recessed to avoid being pressed accidentally.
I'm not sure why the front USB port is so recessed. Some USB keys will not be able to fit into that slot. There is a second USB port on the back that is also recessed but to a lesser degree.
Wow.
At 8.5 inches, the MSOX2024A boasts the "largest screen in its class". The display takes up about 60% of the front face of the scope, and boy is it gorgeous. Colours are vibrant, viewing angles are great.
Agilent have also thoughtfully dedicated the majority of the screen to the waveforms. (On some other scopes I've worked with, half the display is taken up with information about soft-buttons and measurements.)
The screen was also a main attraction when I showed the unit to my colleagues at work - they were amazed at its clarity and rapid update rate.
The MSOX2024A really shines when it comes to analogue. The large high-resolution display and ultra-fast waveform update rate combined make it easy to work with multiple signals. It's a real pleasure to use.
Here's an example where I'm looking at a noisy insertion of a USB cable.
I'm not entirely happy with the probes that shipped with the oscilloscope. Don't get me wrong, they perform fine, but feel a little cheap. There are a number of little things which in my opinion could be improved:
It seems like the probes are excessively long, more so with the "hats" on.
The hats require quite some force before they click onto the probe.
Some of the colours of the clips to help you identify each probe don't match the colours of the waveforms on screen.
This is one area that Agilent could improve.
I'll start by saying the digital probes are excellent. The cable between the probes and the scope is a woven mesh which feels indestructible. The digital probe kit also comes with little hook grabbers in case you want to attach to IC pins.
Eight channels of digital input are supported. The display of digital data on the screen is clear, easy to follow. The logic thresholds can be changed to TTL/CMOS/ECL preset, or user-defined. Note there is only a single threshold setting which applies to all digital inputs.
Along with the option of viewing all 8 inputs separately, you can group the digital inputs into one of two buses and view the bus value as a binary or hex value.
It's possible to display all 4 analogue signals and 8 digital signals on the screen at once, but in practice this is quite crowded and makes it hard to distinguish the signals. Using the bus view instead of individual digital channels makes this easier.
One of my concerns when starting with this scope was that with so many features the unit would be difficult to use, or at least have a sharp learning curve. Well, I'm pleased to report that in fact the converse is mostly true: all the basic functionality is easily accessible from the front panel. The soft-buttons below the screen are used for context-sensitive options and there's a handy 'Back' button to navigate up to the previous level.
Experienced Agilent users will feel right at home with the user interface, which is fairly consistent across their oscilloscope range. I did have to refer to the documentation on a couple of occasions and found it very thorough.
There is a "Quick Action" button which can be configured to run a custom action. I set my unit up to save the current waveforms as a PNG file on an attached USB drive. This is something that I do often, and it's useful to be able to do it with a single key-press.
The "Label" button allows you to annotate the waveforms by assigning a name to each channel. The scope comes with a predefined list of common names (CLOCK, MOSI, etc), but you can also add your own. By far the quickest way to enter a new label is to plug in an external USB keyboard and just type it in. There does not seem to be an easy way to revert the label back to its default once it has been set (although Default Setup will reset all label names).
The standard trigger types available are:
edge
pulse
video
pattern - triggers when the digital channels match the chosen pattern
With the serial-decoding options installed, it is also possible to trigger on I2C/LIN/CAN/RS232/SPI.
If you have the waveform generator option, you can also use the output from the waveform generator as the trigger source.
I would have liked to have seen the ability for more advanced triggers, for instance to trigger on runt pulses or "edge then edge". To be fair though, these are features that the average user is probably not going to need.
Out of the box, connectivity is limited. There are 2 USB host ports, which can be used to attach thumb drives to save/load waveforms and settings, or a keyboard to assist with labelling of channels.
If you want to control the scope with a PC, you can connect using the USB-B port on the back. This requires installation of the Agilent IO libraries (a VISA implementation) which are freely available online.
Once your scope is hooked up to the PC via USB and the Agilent IO libraries are installed, you can then install Agilent Oscilloscope Mobile Agent. This is where things get really interesting. Agilent provides free mobile applications (for Android and IOS) which allow you to control the scope from your tablet or mobile phone! There are some limitations (for example, only analog channels are supported), but the interface is touch-friendly and top-notch. I especially like the ability to save screenshots straight to the mobile device.
An optional VGA/LAN expansion board is available, as is a GPIB interface (but not both at the same time). Apparently the LAN expansion comes with a web interface to access the scope display and controls.
Agilent also sell InfiniiView analysis software to allow control of the scope from the PC. I did not try this, but it could save time when recording and annotating waveforms for documentation or debugging purposes.
The digital voltmeter, enabled by the DSOXDVM option, adds the ability to automatically display voltage or frequency for a single channel. This differs from the regular measurements as the reading is shown as a much larger seven-segment display. This makes reading the number from a distance much easier - I am able to stand more than 3 meters away from the oscilloscope and still read the DVM display without difficulty. This is definitely handy when you need to probe something which is not right by the oscilloscope.
This DVM display is completely separate from the regular measurements facilities (which are available free on all models), but I'm not a fan of this approach. Instead of having 2 distinct systems to measure the waveforms, why didn't Agilent just allow any of the normal measurements to be displayed using a larger font? This would make this option much more powerful.
Note that the normal retail price for this privilege is US$76. I think Agilent should consider adding this feature as standard.
Agilent offers a number of options for enabling additional features. Mostly the new functionality is enabled using a software licence, for example to enable the built-in Function Generator or Digital Voltmeter.
These options are fairly pricey, but keep your eyes peeled - Agilent has run "buy 1, get 1 free" deals in the past which make things more affordable.
Of the options, I think the most useful will be DSOX2MEMUP, which increases memory from the standard 100 kpts per channel to 1 Mpts per channel. It's fantastic to be able to acquire a signal at a large time-base and then be able to zoom all the way in to a region of interest.
Full details of all options and accessories are available on this page. Free 30-day trials of most options are also available.
Agilent kindly made their serial protocol decoding options available for this roadtest.
It's very easy to set-up. You hit the 'Serial' button, select the mode and the inputs and any other options, and you're ready to go. There is also a Lister showing a table of timestamped serial events.
One limitation is that even though there are 8 channels of digital inputs available, you can only select the analogue inputs on the MSOX2024A for serial protocol decoding. I2C only requires 2 lines, leaving 2 spare for normal analogue use, but in the case of SPI, all 4 of your analogue channels could be used for serial decoding.
Another surprise is that you cannot use serial decoding and display the digital inputs at the same time. This seems strange given that the digital inputs can't actually be used for serial decoding.
Like DVM and serial-decoding, the waveform generator is an optional addon. The internals of the scope contain all the necessary hardware, but a software license is required to activate the feature.
As far as waveform generators go, the specs are a little tame: up to 20MHz for sine waves, and 10MHz for square waves. Feature set is good, with support for AM/FM/FSK modulation and the ability to add noise to the output waveform.
The interface to control the waveform generator is simple and intuitive. The waveform type, the frequency, amplitude and DC offset are adjustable from the main Wave Gen menu. There is no direct display of the generator waveform on the screen, to view it you'll need to hook the output to one of the analog inputs.
Using the math FFT function on the scope, I can see the output of the waveform generator has a 125MHz component - this must be the internal switching frequency.
Like all engineers, I love to know how things work. I was not game enough to pull apart my unit, but luckily I didn't have to. Dave Jones of EEVBLOG has a video showing a full tear-down of the unit. You can watch it here, it's well worth a look.
I also found the Agilent website to be a great resource - the latest documentation and firmware/software updates are available along with training videos and application notes.
The MSOX2024A is a fantastic unit in both looks and function. It feels well-designed and well-built and I am more than happy with its analogue and digital performance. It surpasses my old scope in every way. In fact since receiving the MSOX2024A, the Tektronix TDS has sat on the shelf gathering dust.
What's interesting is that in some ways I was previously unaware of what I was missing out on. I was used to having to deal with slow waveform updates and low screen resolution. The deeper memory and analogue performance of the MSOX2024A have already saved me time and frustration. The glorious screen and digital/serial decoding capabilities are like icing on the cake.
The unit is almost flawless, but there's a few things it loses points for. While the DVM option can be a useful addition, Agilent should have included this functionality as standard and it should be enhanced to allow any measurement to be displayed.
The fact that serial decoding (assuming you have bought the option) is only supported on the analogue inputs is disappointing. This means the MSOX2024A is often limited to being a logic analyser OR protocol analyser OR oscilloscope, rather than a logic analyser AND protocol analyser AND oscilloscope.
These niggles aside, I recommend the MSOX2024A as an excellent easy-to-use mixed-signal oscilloscope, a suitable candidate for the professional or serious hobbyist. Those who are more cautious with their budget may decide a lower-end model will be sufficient. Agilent offers a number of models which differ solely in terms of bandwidth (70/100/200 MHz), number of channels (2 vs 4) and whether digital inputs are included (MSOX vs DSOX). These models are all upgradeable to the equivalent of the MSOX2024A (except for upgrading from 2 to 4 analogue channels!) , allowing you to get a more affordable unit up-front. I also notice Agilent are running a promotion until the end of March 2014 giving you a free upgrade in bandwidth. Further details are available at this page.
If budget is less of an issue, you might be more interested in Agilent's MSOX3000 series. It's a big brother to the MSOX2000 series, with a similar user interface, but offers a higher bandwidth and 16 digital channels. It also has the ability to use the digital inputs for serial decoding, leaving the analogue channels free for analogue capturing.
Special mention goes to Christian of Element 14 and Joe of Agilent for assistance in getting the review unit to me.
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An addendum:
One of the ways manufacturers are keeping their scope prices down is to provide a basic (scope-only) model and then charge extra for addons (eg. serial protocol decoders, waveform generator…