which oscilloscope?

Hello,

My boss asked me to evaluate oscilloscopes and to recommend one. I know Tektronix and LeCroy. Which is better? Are they any others? Ideally, we would get a 4-channel scope at 300 MHz, with a 5 million sample record length. Thanks for your advise.

T.I.

Reply to
Talal Itani
Loading thread data ...

Agilent scopes are nice, too. Some scope companies have local resellers, which can demonstrate their products at your workplace and even lend you a scope for some days, so you can evaluate it yourself, if it fits your needs.

--
Frank Buss, fb@frank-buss.de
http://www.frank-buss.de, http://www.it4-systems.de
Reply to
Frank Buss

Google is your friend. Find a broker, and then pick brands from that. eg

formatting link

-jg

Reply to
Jim Granville

Agilent is the other "big one". In fact Tektronix and Algilent are the "big two" brands, Lecroy has always come third.

Lecroy have a bad rep for being hard to drive, the newer ones are better though.

IMO the Agilent's are the easiest and nicest to drive.

The Agilent DSO6034A suits your requirement:

formatting link

300MHz, 8Mpoint memory, 4 channel A very very nice scope.

You'll need more specific requirements than that to compare scopes in this category. Any specific uses in mind? e.g. do you need mixed signal analysis?, high speed serial protocol analysis?, what sample rate?

Dave.

Reply to
David L. Jones

formatting link

Or the new 7000 series Agilent:

formatting link

12.1" XGA display!

Dave.

Reply to
David L. Jones

It is nice if we can do mixed signal, but I am sure we have to pay much more. We will use this scope in the product development lab, for embedded work. The signal we are working with is 25MHz digital. Rarely we will look at a clock of 100 MHz. So, I thought 350 MHz analog is what we should get. Some Tektronix and LeCroy have a very short buffer. The ones with large buffer start at $5,000. Is one brand better priced than the others?

Thanks.

formatting link

Reply to
Talal Itani

LeCroy is evil. Weird, too.

John

Reply to
John Larkin

For embedded stuff, get a color digital scope. Analog scopes have zero buffer!

We have one of these...

formatting link

a 2024, and it's the best general-purpose scope around. The fully-floating inputs are fabulous.

John

Reply to
John Larkin

I second that. We bought 4 x 350MHz 4 channel digital LeCroy scopes last year as a 'special deal'.

They are total crap - based on a PC chassis. Take ages to boot first thing in the morning, are forever 'calibrating' - (no you can't turn it off!) - and while calibrating are unusable. As they are embedded PC based the refresh rate is pants as well - sort of 10Hz if you are lucky.

LeCroys are bottom of the heap crap IMHO.

The digital Tektronix scopes we have on the other hand are superb - actually designed to use as a scope, fast, reliable workhorses.

Reply to
Icky Thwacket

Thanks. This is nice stuff, yet the buffer length (2.4k points) is too small, I think, for our needs.

Reply to
Talal Itani

Evil as in Sinner?

Reply to
Talal Itani

(John L. has some personal business wrt LeCroy--sort of like me with Apple. Search back through the archives.)

Old LeCroys had some interesting features, though...I have an ancient

9400 that was the first digitizing scope to scroll the display at slow speeds, like a chart recorder, and let you move the viewing window with the horizontal position knob even while it was taking data. Very very useful for some things.

They have never known how to build vertical amplifiers, AFAIK--at one point they were selling a 2Gs/s scope with a 350 MHz vertical BW. Pathetic.

Cheers,

Phil Hobbs

Reply to
Phil Hobbs

Why do you need a lot of buffer? I test and debug realtime uP-based things, delay generators and arbs and such, with a Tek TDS2012, which only has enough buffer for the screen you see.

At some point, a lot of memory is too much memory. It's easier to think about why something's broken than to analyze a few million stored events. Even easier to design it right in the first place, ie, review the design more, debug it less.

John

Reply to
John Larkin

Yup, they tried to put me out of business. Our friend at Los Alamos didn't let them. That same guy, Harry, swears he was the one who convinced Walter to take his CAMAC digitizer technology into the scope business.

So, what's the story on Apple?

I doubt they can spend as many megabucks on fast adc's as can Tek or Agilent. Anybody can interleave a bunch of slow adc's.

They did a lot of strange stuff when Walter was still running things. One was a scope with a ccd-like analog-storage shift register that captured a small slice of transient data and time-shifted it down into an adc. Occasionally. Spliced into the front end of a gp scope, it made a very weird machine.

They also did a 1-diode sampler (Lumatron/typeN blast from the past, fer sure) and a heterodyne-based sampling scope timebase. I think they may have been mixed up with the PSPL shockline sampler fiasco... not sure about that one.

LeCroy scopes seem to appeal to, err, a certain subset of the population.

I have some Lumatron sampler schematics around here somewhere; even some old rusty hardware.

John

Reply to
John Larkin

One of my clients has a top analog engineer who, when given the choice between getting a dozen $3500 scopes so his whole department can work without constantly stealing equipment vs. getting one $45000 scope so he can measure really fast signals will immediately call Tek, Agilent and LeCroy and ask for them to come out and bring their heavy iron.

For the absolute top of the line stuff LeCroy seems to be quite good -- their triggering sucks, but they can (some years) sample faster than anyone else. At that price point _all_ the scopes are Windows based, and they're all pretty bizarre bits of equipment if all you want to do is see if a processor pin is wiggling at 100kHz.

For the 300MHz range I'd look to Tek or Agilent, although there's a new top of the line Asian brand whose name I can't remember that may be a good choice (they aren't really new -- they had a deal with HP to not sell scopes in North America as long as HP sold scopes; as soon as HP spun off Agilent they were there, chuckling over their good fortune).

--
Tim Wescott
Wescott Design Services
 Click to see the full signature
Reply to
Tim Wescott

Not having to think or jump through hoops to trigger at the right point can save a lot of time. That is where a big buffer comes in handy. Also being able to zoom in at a 'problem spot' without having to re-capture data saves a lot of time and hassle. I do a lot of checking on FPGA designs using a 2M point logic analyzer. One acquisition usually gives me all the data I need to verify the design.

--
Programmeren in Almere?
E-mail naar nico@nctdevpuntnl (punt=.)
Reply to
Nico Coesel

When I was a graduate student at Stanford in 1984, Apple ran a promotion where they sold 128K Macintoshes to students for about half price ($1100, iirc), along with the fairly nice 9-pin dot matrix graphics printer for another $400. I had some code and a thesis to write, and I thought it would be pretty useful.

That was a lot of money to me at the time--I was already married, and my wife couldn't work in the US, so it was two of us living on a grad student's stipend. I also knew perfectly well that you needed at least half a megabyte of RAM to do anything useful (even with the GUI in ROM, which was the big selling point of the Mac at that time). However, Apple had a track record (then) of being relatively generous about upgrades--they'd upgraded their Apple Lisa customers for a very reasonable price, and with the Apple II/III, they'd shown that they understood the importance of the educational market. So I was optimistic that the 512K upgrade was going to be reasonably priced. I mean, even then that was about $100 worth of memory chips, so how expensive could it be?

What actually happened was that they charged $1000 for the upgrade, which amounted to desoldering the 16 (DIP) 4164 chips and soldering in

16 41256s. They attempted to strong-arm everyone into ponying up by saying that only factory upgraded machines would function with future Apple products.

That turned into a bit of a habit with them--they recently did basically the same thing to all the iPhone customers who changed their firmware, except that my computer at least kept working.

After the shooting pains in the backside died away, I calmly decided that I didn't want to play that particular game. I've never bought an Apple product since.

Cheers,

Phil Hobbs

Reply to
Phil Hobbs

I have a Tektronix at home, with the 2.k point, and at times it is painful to use. I see myself trying to scroll and scroll, to see more, and then I realize that the scope cannot show me more. We are debugging some serial protocols, so a buffer larger than 2.4 is really needed.

Reply to
Talal Itani

You really want a logic analyser for that rather than an oscilloscope. You get more triggering options generally and since you only need a single bit per sample much greater storage depth for the same memory. You can get combined scope/logic analyzers like the Agilent MSOs

formatting link
&cc=US&lc=eng that additionally make it easy to trigger digital collection from the analog channels or vice versa. As an added advantage you can generally get a number of logic channels for the cost of an analog channels.

Robert

** Posted from
formatting link
**
Reply to
Robert Adsett

Well, the good Lecroys say Iwatsu on the inside :-)

--
Programmeren in Almere?
E-mail naar nico@nctdevpuntnl (punt=.)
Reply to
Nico Coesel

ElectronDepot website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.