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User Interface of Major Oscilliscope Brands?
teddaw152 writes "I've been tasked with ordering an oscilloscope and a logic analyzer for use in a university physics lab, and have found several models that will likely suit our technical needs from the major manufacturers (Agilent, Tektronix, and LeCroy). However, I personally have only used legacy HP scopes, and thus I have no idea what modern features are must haves and which brand's user interface is the most intuitive. Is there anyone out there that has used modern Tektronix/Agilent/LeCroy scopes side by side and can comment on their thoughts from the purely subjective side?"
The most important feature, and I cannot stress this enough, is that the oscilloscope be able to display wavy lines. I once got a discount oscilloscope from a back alley dealer, and all it could display was straight diagonal lines. It was an unmitigated disaster.
Not another scopes trial!
Are you really going to come to slashdot with a question including
"I have no idea what modern features are must haves and which brand's user interface is the most intuitive."
The clear answer to your dilemma is that the task should have fallen on someone else. Who is going to be using these things? If it's you, maybe you are best to stick with legacy HP scopes until you figure out what it is that you want.
Assuming there still is one in your area, you might ask the folks at your local amateur radio club. They are more likely than the Slashdot crowd to be familiar with the use of oscilliscopes.
Dude, If you feel comfortable with the old HP, you have to remember that Agilent was spun off of HP back in 2000. Maybe the Agilent one is more to your liking.
I saw a LeCroy we have -- about $10K -- that was freaking amazing. Plugs into a network, has USB, can store waveforms, zoom, virtually unlimited capture, freaking AUTOMATICALLY figured out which serial standard was being used to generate the waveform (the first -- and perhaps only -- time that "autoconfigure" really did the job), etc. They're good. Unless Agilent and Tektronix have come a looong way, LeCroy is going to be the one to beat.
$.02
What range of scope are you looking for? It really depends on which end of the spectrum. In the 100 and 200 MHz range, I think Tektronix blows everyone else out of the water. When you get to the 500 MHz and Gigahertz stuff, I think Tek still has the price advantage, and ease of use, but the competition is a lot closer. All three manufacturers know what the others are offering and price accordingly. I have seen LeCroy ones lock up with a LeCroy rep operating them. On the real high end, the Tektronix logic analyzers can interface with the scopes to give a coherent display of both digital and analog data. The best way to choose is the call the local reps and use a loaner model for a week or so.
-- the computer doesn't want any beer, no matter how much you think it does. NEVER, EVER feed your computer beer.
A few points of advice.
Agilent lets you connect a scope to the logic analyzer and display both waveforms on the same screen.
I did extensive evaluation on the UIs of Tek, Agilent, and Lecroy when I bought. All were approximately comparable. All had things that were great and some that sucked. You should be able to get a demo from sales and possibly keep it for a month.
Do you really need / want a logic analyzer? Unless you're doing FPGAs or pure-digital boards with lots of parallel buses, get a Mixed Signal Oscilloscope instead. They'll decode RS-232, SPI, I2C, and so on and display it on-screen. My high-end scope and logic analyzer lack these features and I am kicking myself. I mostly do microcontroller work and an MSO would have been far more usable. I'm not sure if I have ever even used the logic analyzer.
All old HP scopes were made by the division that is now Agilent. Depending on how old your old HP scopes are, they may resemble newer Agilent scopes the closest. Features have changed a lot in 10, 20, and 30 years on these devices.
Depending on the resources in your lab, and its purposes, you might find that a software-defined interface is more flexible for your needs. You can add any sort of interface or processing capabilities you want.
http://sine.ni.com/nips/cds/view/p/lang/en/nid/205615
If it's a research lab, something like the above may be just what you want. If it's a teaching lab, and you want students to have access to real knobs and buttons, then my experience is specifically with Tektronix scopes that I use at work. Again, without knowing your price range, there are a wide range of options out there.
At the low end, the TDS5054B series has an interface likely identical to that of your old scope; they did a reasonable job of replicating the older style of analog interface but added on some processing utilities.
http://www.tek.com/products/oscilloscopes/tds5000b/
I've used a scope the DPO400 series as well. I found it's interface to be rather, well, different at first, with all the options not in the places I'd usually expect them to be with my other Tek scopes. But I eventually grew used to it and found it all perfectly fine - except that the probe connections for some reason don't allow use of our current probes. They work fine on all other scopes, and I see no reason why they molded the plastic on this scope to exclude them.
http://www.tek.com/products/oscilloscopes/dpo4000/
Finally, at the high end, you have something like the DSA8200. This scope runs windows, which you can get to to do some data analysis, but the scope itself is controlled through the Tek application. It looks and behaves like a piece of software; there are buttons on the front for some features, but they are just macro buttons to execute the commands; it's often faster to just use a mouse since the buttons only offer limited functionality.
http://www.tek.com/products/oscilloscopes/dsa8200/
Note how the Tek scopes are all mostly more expensive than the NI scope, with more limited flexiblity in the interface. Again, if I knew what bandwidth you needed or what your budget was or the purpose of your lab, I could give better recommendations.
It doesn't hurt to be nice.
It runs Windows 2000 and takes a cup of coffee to boot up but runs nicely.
We tried Agilent scopes (we were able to try-before-buy) and found them easier to use, more compact, less bloat that the LeCroy.
I think its hard to go wrong with modern oscilloscopes.
But they only have a 200 kHz input bandwidth!
I second this - if you really don't know what to buy, then do the following:
Find your local Agilent (HP), Tek and LeCroy sales reps and give them a call with your needs, and let them recommend you which line of 'scopes will fit your needs best (do you need mixed signal, digital decode, etc). Then go to their websites and research those scopes to narrow down the models to 1 or 2 at most. (They all make tons of scope models, and each has their own ton of options that can be bought with them. The sales guy will help you narrow down that list.)
Call up the reps again and ask for a loaner to try them out - they'll normally give you a week or two to play with them. Play with all the scopes and try to do what the people in the lab do. At the end, find out what features you like, which were redundant, and phone the reps again asking to see if a different model may suit your needs better after having used them.
Lather, rinse, repeat.
If you're going to be buying many of them, mention it to the sales rep, and also the fact you're buying for university - they'll be more accommodating in loaning you units. One thing they would appreciate is feedback on the units - if something really sucks, they want to know about it
Once you've got a list of several scopes that will suit your needs, it's discussion time about prices and discounts.
But do take advantage of the fact that the sales reps will often loan you equipment.
Must haves? What? Besides being able to show a sine, square, and sawtooth waveform, what more are you looking for? Even the legacy oscilloscopes from HP that I've used has had a lot of the modern features that you see on the newer ones today. Sure, the newer ones do certain things more nicely, but there honestly isn't a huge difference, unless you're looking for things like color, USB support for capturing waveforms, super accurate frequency readings, etc... What you need to do is figure out what specifically is going to be needed with whatever projects you're doing.
This is what I use at work. (Specifically the TDS2000B.) I have no complaints with it. I've found this to be intuitive to use. It's simple and robust for what it is. Other people around me have to use the TDS1000B, and really the only difference is the lack of a multicolor display, USB support, and only 2 channels. I haven't had any issues showing our "trained monkeys" (pre-testers who have zero training or education in electronics) on how to use these oscilloscopes.
As a software developer who's trying to learn about hardware, I find the timing of this question quite valuable, as I have a related question.
I'm interested in getting an oscope for my home learning. Typical beginner circuits (low power, inductors, breadboard etc).
Could someone who has more experience in this than I please give some recommendations for a new scope to buy?
The standard Physics lab ones are expensive (or at least they used to be). I'm a little hesitant to pick one up off of ebay, sight unseen.
Any recommendations here for a new one within the budget of a home hobbiest?
Many thanks in advance.
I think its hard to go wrong with modern oscilloscopes.
Well, at my University, about 25 years ago, they started a energy saving plan, and turned off the heat in the classrooms and labs at night. Being that computer/electronics geeks tend to be nocturnal, we were freezing our balls off. So we scrounged up every available big old Tektronix honkers, vintage HP wave generators, anything with TUBES gathering dust in corners somewhere in the department.
We had the place up to sauna temperature.
So, do not neglect the tube factor. Plus, audiophiles claim that tubes are better anyway.
And plan to spend more for your connecting cables, as for the oscilloscope. Big, fat, "Monster" ones, made out of iridium, platinum tipped.
I think I really miss those old Tektronix tubies ... they made a real *whack* when you turned them on, and you could look through the perforated cover to see the tubes light up.
Schroedinger's Brexit: The UK is both in and out of the EU at the same time!
I'll start with the open admission that I've worked on Tektronix scope platforms, including software UI development, for the last 7 years or so. That said, our scopes really are the best! Here's why.
Many of the Tek scopes, especially the lower bandwidth ones, really shy away from loads of options menus to get at items. We still have the knob-per-channel ideas, and I know from user testing that's always heavily favored.
Recently (last 2 years) we've also gotten into the pan/zoom knob that makes it far, far easier to look at record lengths. I personally use that feature a lot when I've got high speed stuff over a long time (like SPI transactions compared against analog signals moving around)
Most of the Agilent/Lecroy stuff don't have these two big items (those are my big payoffs).
Also, although I can't speak to Agilent/Lecroy, I know that we release updated firmware on a very regular basis, and have no plans to stop. We continue to improve the UI, performance, applications, etc., long after the product is released. Many of the changes are often directly from user feedback (internal and external).
Another nice part is the Tektronix instruments are very well plugged in driver wise to communicate with them. We've got IVI drivers for labview/teststand, as well as a host of others.
What some of the other posters said is true as well - what really defines what you should get isn't always the UI, but the bandwidth and other features that you need. If you just need slow speed (~10 MHz) then a cheap solution might be just fine.
Our designs do have their flaws, but usability is rarely one I hear of.
Do what my TA's do. Create a Wheatstone bridge and have your students ride an exercise bike until current balances out. The speed's your curve.
Everyone expressing an opinion based on experience is dead right, teddaw152 - I've used all three and can say I see no BS.
But you're missing a most important criterion - how easy will it be to offload your data, because I don't care what you think your requirement is or will be, you're going to need this badly - or the next user will.
For any given model of features/performance/price tickling your fancy, insist to see the full configuration used to offload data to a PC.
I'm dead serious, full configuration. Do not ever accept rep claims of way-easy-all-our-customers-do-it, do not accept quick looks at user manuals showing code slices that make it all so obvious.
Do not accept that USB, GPIB, or Ethernet obviously imply that you can do this.
Do require code that:
1. Is in a language that your site will support long term
2. Allows for external configuration of the scope
3. Allows for external software trigger of recording
4. Allows for data acquisition by a PC
5. Allows for usable data, post acquisition
PLEASE USE THIS DEFINITION ONLY FOR THE WORDS "Allows for" IN THE ABOVE:
1. Full source code in your selected language
2. Full clarity of hardware interface required - price, performance and gotchas
3. You get a peer review of this
For "usable data" this damn well means that the data feed of (usually) start-time, stop-time, delta-time and Y values or X-Y pairs can not only be read in, they can be easily read in, easily put into another format, and easily absorbed by other post-processing software.
And for god's sake, make sure that status register and SRQ handling - in software - is clearly explained, and that you get routines for SRQ handling, and THE RULES FOR WHEN TO USE SRQs or NOT (typical GPIB issue).
I disclose that I have inside info on the brands you consider so I can only give these hints on approaching the problem. I cannot be trusted to be objective - due to associations - on saying which brands/models excel on this.
But I can be trusted to tell you this - your rep for any given brand will shuck and jive a *little* (and that really is an OK thing, it's a people skill), and he/she will give you assurances out the yin-yang (that's their job) - but they fucking-a well know what you're asking and will give you the straight dope if you are friendly while being persistent.
Please believe me, if you overlook this criterion now, you're almost guaranteed to screw the next guys after you - I don't believe you'd want that if you had a choice.
Cheers, best luck.
Pathological kinda promises Path + Logical - but instead, you get stuck with pathetic.
I use tektronix scopes pretty much daily. Almost all of their new stuff, except for the very low end, is Windows based, which, besides the regular negative slashdot bias against windows, can be a real pain when you work in a closed lab with special security rules. Windows (and Unix) boxes are severely tied down in most security sensitive situations, and these scopes either require you to run as admin, or as a non-admin you lose a lot of functionality.
One of our brilliant IT security folks installed a program called Device-Lock on my Tek scope the other day. This was configured to completely disabled all I/O (except mouse/keyboard) on the scope, which is kind of funny considering the purpose of a scope. We got this fixed, after a long and entertaining conversation with security.
This issue doesn't apply to the submitter most likely, but anyone else reading and looking for advice, take into account rules regarding OS security at your work / school when looking at a new scope. Frequently I will look for one of the older scopes running proprietary OSes (like the old HPs) to avoid the hassle entirely. To answer your original question, you really need to define requirements before your start picking out scopes. It's like buying a vehicle with your only criteria being it's color.
I highly doubt that you will find ...
(1) *qualified* people who've used oscilloscopes from all three of these manufacturers
(2) *and* who are willing to take the time to write out a lengthy reply to your questions.
You are, however, likely to find people who've used 1 brand (largely because their employers/universities had a contract with a specific supplier). So you may get some firm opinions about one company or another, but probably not much unbiased consensus.
So, the only way to form a complete, impartial comparison is for you to try out the scopes yourself; contact an authorized dealer for each of the major manufacturers, and ask to try out the models in your price range.
Doing your own due diligence is the only way that you'll be able to answer your questions to any high degree of satisfaction. This isn't an example of where you should trust random comments from the interwebz to help you do your job.
Agilent will definitely do loaners. I'm not sure about LeCroy. There are essentially three models of scopes. The lowest tier gets you the scopes you remember - analog, limited digital capability, probably little capture memory - those are about $5k USD or less. The middle tier gets you digital scope, shallow memory, some math functions, typically data rates to about 500Mhz. Those can cost up to about $20k depending on your individual wishes. The top tier can cost $50k or more for some features. They have math modules that you buy and install, deep memories, USB ports, sampling rates up to Ghz, measurement, logic analysis, just about anything you could ever want. Personally I've been using LeCroy WavePros for years - they're windows-based platforms for what that's worth. The interface was highly non-intuitive but really came to grow on me. They use context-reactive controls that can be very confusing at first but become very powerful as you get used to them. Then recently borrowed a high end Tektronix. Didn't like it at first, couldn't get used to the sort of "classic" control scheme they use, but then got used to those as well. Found the high-end scopes from LeCroy and Tektronix overall very comparable.
Jealously hoarding mod points since 2007.
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Agilent has a modular USB oscilloscope with 200 MHz bandwidth. Though, it is 10x more expensive than the Parallax model recommended by GP. You control it through software front panels or program your own via IVI drivers (both provided).
I use oscilloscopes almost daily in my job as an EE, and I've found that I very much prefer the scopes that don't use Windows in any shape or form to the ones that do. If a scope requires a mouse, it's really a portable computer with an integrated DAC subsystem. You have to wait for it to boot up and shut down, and you have to have the flat space necessary to drive the mouse (or use a trackball). They are also generally less responsive to input and take longer to change modes than an embedded-system style scope.
My current desk unit is a Tektronix MSO 4054, which is ideal for what I do. Everything is adjusted using good old-fashioned knobs and buttons on the front panel. I also use several higher-end Teks that run Windows and various Agilent scopes, both from the 54600-series and the Infinium series.
It's true that the Windows-based scopes can often run other software and do more detailed analysis of data. However, I prefer to use the scope to acquire data, store it on a USB drive and then do that analysis at my desk later using my main computer.
In our corporate environment, having oscilloscopes on the network is frowned upon by our IT.
My dislike for oscilloscopes that run Windows is shared by most of my EE and technician colleagues. Non-EE types (physicists, MEs) seem to like the Windows interface because they use the scopes less often and they feel more at home with a PC-like interface.
In another vein, I despise touch screens. This is simply my personal preference, as I realize that many people like the way they link the data on screen to actions. I just hate fingerprints, and the tactile feedback provided by real buttons and knobs is far superior in my mind.
Spent a minute trying to understand the above comment... it must be a joke. Straight diagonal lines would be a characteristic of a digital storage scope with serious Analog-to-Digital converter problems.
Although it wouldn't be used in a university physics lab, I suggest Slashdot readers download a free PC sound-card-oscilloscope program. They are basically *free* Digital Storage Scopes with a limited input frequency of 44KHz to 96KHz depending on the particular sound chip in the PC. Many of these programs include spectrum analysis and FFT features.
These are invaluable for audio and other low frequency work. It's necessary to scale the input to the sound card to about 1-2 volts peak-to-peak max, because these programs are working with the audio line-input signal. A couple of $0.40 op-amps work fine. I've used *free* sound card oscilloscopes to verify MIDI in/out streams from synthesizers, RS-232 signals, and the design/repair/calibration of hundreds of guitar stompbox circuits.