Maker Pro
Maker Pro

O'scopes - Tek vs HP/Agilent vs LeCroy

D

Dave

Scopes should have knobs and screens.

And a polaroid camera with the little "fixer" container that was so handy
for spraying freeze spray into, snapping the top back on, and throwing
under someones desk or chair. Then waiting innocently to see how they
jumped when it popped the top off. Ahh, those were the days! ;-))


~Dave~
 
D

David L. Jones

Nico said:
I like the mixed signal oscilloscopes from HP. Loads of memory and not
very difficult to use. Never had problems with the trigger.

I second that.
The new 6000 series mixed signal Agilent scopes are supurb. Plenty of
sample memory, very intuitive to use, and no problems with triggering.
The LA part is not as powerful triggering wise as a full blown LA, but
still very usuable for most work.

I would not touch a Lecroy. The older ones were a nightmare to drive.
I've heard the newer Waverunner series is supposed to be a bit better
in this respect, but I have not used one so can't comment.

Dave :)
 
D

Data

John said:
That actually makes sense for data-intensive things like logic
analyzers and maybe spectrum analyzers. Scopes should have knobs and
screens.

I quite agree with you actually -- and in fact, I hate Windows scopes
even more than I hate Windows logic analysers.

--mpa
 
J

John Larkin

On Fri, 15 Dec 2006 08:27:58 -0800,
John Larkin wrote


Why?

robert

I'm still mad at them for something that happened 15 years ago. One of
my customers, from a national lab, was disgusted with their quality
and service on some time-to-digital converters, their 4208. Half of
them were DOA, it took 6 months to recycle the duds (through
Switzerland), and half the reworks were DOA. So I designed a
functional equivalent, *not* a copy. Next time Harry went out for
bids, LeCroy cut their price in half, just to kill us off.

Bless Harry, he disqualified them on technical grounds and I got into
the picosecond electronics business.

Walter thought he'd invented the nanosecond and resented anybody else
who tried to do fast stuff.

John
 
J

Joel Kolstad

Data said:
That doesn't mean it's the right direction.

True, although my opinion is that for complicated test instruments such as
analyzers & scopes, how well the software works has much more to do with the
programmers than with the underlying OS.
And one that crashes frequently

That is generally indicative of bad programmers, not bad OS design. Yes,
Windows (and every other commercial OS out there) has bugs (tons of 'em), but
for every PC that crashes probably only 1 in 1000 if not 10000 does so due to
an OS bug rather than an application or 3rd-party driver bug.
and requires security patches (the
idea!)

If you keep your instrument off the network -- or within a well-firewalled
intranet -- realistically the security patches are highly optional. ANY
instrument -- regardless of OS -- that's sitting directly on the Internet
needs to be kept up-to-date security patch-wise.

This is really only an issue because older instruments didn't *have* TCP/IP
connectivity...
and spends gobs of time booting up

In my experience, QNX, Linux, Windows, and VxWorks all take roughly comparable
(same order of magnitude) times to boot, although I've seen people pay a lot
more attention to getting QNX and VxWorks to boot *quickly*. Of all 4, Linux
is probably the slowest, since it doesn't have the fancy background service
that Windows does that specifically goes around trying to impove your boot
times (but still has just as many services to load).
and uses special PC
components that go obsolete in six months, and special hard drives that
come in special cases so you can't repair them yourself, and so the
maker can charge you ungodly parts & labour cost, is also a giant waste
of time.

Umm... have you hung out on any of the groups where people discuss trying to
clone old instruments' EEPROMs to try to get a dead one working? Or how to
read some proprietary disk imagine format from a 20-year-old instrument? I'd
much rather take my chances with a common PC platform -- even if the
manufacturer has added proprietary disk cases or something -- than with true
fully-custom platforms.
I hated Windows scopes when they first came out, and I still hate them
now (in case you couldn't tell). Not only do they have the same
Fisher-Price feel to them that regular Windows has, they have the same
reliability. A workman is known by his tools.

That's naive... I know workmen by their results; I'm not too concerned with
what tools they use. I've seen plenty of guys with far better tools produce
inferior work to someone with low-end tools just because the later was more
experienced, concerned about quality, whatever.
Besides, I've already got a Windows laptop, which I have to use for
work. If I have to use Windows on an instrument, I'd rather just use my
laptop, which has a bigger screen, an attached keyboard, and a known
set of foibles. So give me the PicoScope-type instruments any day, if
Windows has to be in the mix.

There's a good market for that sort of instrument, and they are quite useful,
but there's always going to be demand for an instrument with its own box, its
own custom controls (knobs and buttons), etc.

You have done plenty of complaining :) and made some good points, but let me
query you -- what OS would you *prefer* manufacturers of test equipment to
use?

---Joel
 
D

Data

I don't mean to top-post -- this is a preface: I hear the slow,
agonising creak of my arguments being demolished, one by one, by a
technician .. and yet .. and yet .. I am too much a romantic to give up
altogether (it's nothing I'm proud of). Nevertheless,

Joel said:
True, although my opinion is that for complicated test instruments such as
analyzers & scopes, how well the software works has much more to do with the
programmers than with the underlying OS.

That's difficult to argue against.
That is generally indicative of bad programmers, not bad OS design. Yes,
Windows (and every other commercial OS out there) has bugs (tons of 'em), but
for every PC that crashes probably only 1 in 1000 if not 10000 does so due to
an OS bug rather than an application or 3rd-party driver bug.

And that's also quite true. NT is rather a good design at the core, and
most crashes do indeed come from drivers.

There's still a load of horrible design in the things that go around
it: for instance, can there be any reasonable explanation or excuse for
the way USB driver installation is handled in Windows XP? And however
beautiful the heart, it's wrapped in a pig's skin. It feels to me like
it was made by people with no taste and no concern.
If you keep your instrument off the network -- or within a well-firewalled
intranet -- realistically the security patches are highly optional. ANY
instrument -- regardless of OS -- that's sitting directly on the Internet
needs to be kept up-to-date security patch-wise.

This is really only an issue because older instruments didn't *have* TCP/IP
connectivity...

You are completely correct. I cower corrected.
In my experience, QNX, Linux, Windows, and VxWorks all take roughly comparable
(same order of magnitude) times to boot, although I've seen people pay a lot
more attention to getting QNX and VxWorks to boot *quickly*. Of all 4, Linux
is probably the slowest, since it doesn't have the fancy background service
that Windows does that specifically goes around trying to impove your boot
times (but still has just as many services to load).

Once again, a well-made point.

My life-meter is getting dangerously low ..
Umm... have you hung out on any of the groups where people discuss trying to
clone old instruments' EEPROMs to try to get a dead one working? Or how to
read some proprietary disk imagine format from a 20-year-old instrument? I'd
much rather take my chances with a common PC platform -- even if the
manufacturer has added proprietary disk cases or something -- than with true
fully-custom platforms.

Ouch! Ouch! It hurts!

I was really thinking here of the "golden days", which I admittedly
don't remember myself, when (so I have heard) scope repair was a
routine task in a lab.

But those were fully analog scopes, and at any rate it's rarely wise to
talk about how wonderful the old days were, because mostly, they
weren't.
That's naive... I know workmen by their results; I'm not too concerned with
what tools they use. I've seen plenty of guys with far better tools produce
inferior work to someone with low-end tools just because the later was more
experienced, concerned about quality, whatever.

Now, on this one, I do not bend. There's wisdom in that saying; I
didn't invent it. And it remains that if a craftsman uses cheap, flimsy
tools, he will usually not be as good as one who uses good tools,
because a good craftsman will tend to choose good tools -- not
necessarily fancy and expensive ones, but always the *right* ones.

I agree that results must be the measure of everything (well, to a
point). But sometimes I must judge a worker before I've seen results,
and if he is unconcerned about his tools, he is either third-rate or
(much rarer) a craftsman of unusual skill.
There's a good market for that sort of instrument, and they are quite useful,
but there's always going to be demand for an instrument with its own box, its
own custom controls (knobs and buttons), etc.

I didn't mean to say there wasn't -- I'm a tremendous fan of knobs and
buttons (and flashing lights), and the more the better.
You have done plenty of complaining :)

Well, to be honest, I was in a bad mood, and probably shouldn't have
been posting. I'm better today. :)
and made some good points, but let me
query you -- what OS would you *prefer* manufacturers of test equipment to
use?

This is where my inexcusable romanticism and personal prejudices come
to the fore.

I would prefer that they use any OS at all, even Windows, as long as
the instrument itself has a solid feel -- as long as it feels like an
instrument. I want it to be something that isn't cheap -- something
made by people who think, and who care.

But Windows is a special problem, because I regard it as the triumph of
the cheap and second-rate. I don't want my bench infected by its
shoddy, amateurish presence (my own presence fills that quota and then
some). Perhaps I should relax and be more objective -- but it's hard
for an inveterate perfectionist.

Well, sir, if you didn't leave me in a heap on the floor, I at least
require a trip to First Aid. Good work, and good points all.

cheers --mpa
 
J

Joel Kolstad

Hi Data,

Data said:
There's still a load of horrible design in the things that go around
it: for instance, can there be any reasonable explanation or excuse for
the way USB driver installation is handled in Windows XP?

You mean from a programmer's perspective? Or the users?

I'm fairly certain that Windows XP has the capability to perform true "plug
and play -- at least after being prompted to insert the driver CD" and that
all those bits of hardware that warn, "You MUST run our install program BEFORE
connecting the hardware!" are due to programmers who are too
lazy/uneducated/whatever to install their drivers "the Windows way" --
although I wouldn't be surprised if, due to some dumb design in Windows, that
does take more effort than "just run setup.exe first and you'll be fine."
And however
beautiful the heart, it's wrapped in a pig's skin. It feels to me like
it was made by people with no taste and no concern.

I think I agree with you there...
But those were fully analog scopes, and at any rate it's rarely wise to
talk about how wonderful the old days were, because mostly, they
weren't.

Like antique furniture, the stuff that survives often is the really well
designed bits that eveyrone *does* want to remember.
Now, on this one, I do not bend. There's wisdom in that saying; I
didn't invent it. And it remains that if a craftsman uses cheap, flimsy
tools, he will usually not be as good as one who uses good tools,
because a good craftsman will tend to choose good tools -- not
necessarily fancy and expensive ones, but always the *right* ones.

OK, I'll give you that.
I would prefer that they use any OS at all, even Windows, as long as
the instrument itself has a solid feel -- as long as it feels like an
instrument. I want it to be something that isn't cheap -- something
made by people who think, and who care.

I wholeheartedly agree and endorse your viewpoint, and I'm completely
convinced there's plenty of market share for such designs. However, I'm also
not surprised that so much of the equipment we get today is not exactly
"inspired." Devivces are so complicated (i.e., no one single person is going
to design an 802.11 wireless card -- much less a cell phone, a PlayStation 3,
etc. -- starting at the transistor level and finishing with Windows device
drivers in any reasonable time frame) that it tends to require large design
teams, and my experience is that the Law of Large Numbers holds true in these
cases: Once your organization becomes big, even though you can remain quite
competitive, a smaller and smaller percentage of your workers will be the real
stand-outs, the people who really did *think* and *care* about what they were
doing.

As far as I'm aware, about the only way around this problem is to work for (or
start) a smaller company or become a consultant.
But Windows is a special problem, because I regard it as the triumph of
the cheap and second-rate. I don't want my bench infected by its
shoddy, amateurish presence (my own presence fills that quota and then
some). Perhaps I should relax and be more objective -- but it's hard
for an inveterate perfectionist.

I see your point!

---Joel
 
N

Nico Coesel

Joel Kolstad said:
True, although my opinion is that for complicated test instruments such as
analyzers & scopes, how well the software works has much more to do with the
programmers than with the underlying OS.


That is generally indicative of bad programmers, not bad OS design. Yes,
Windows (and every other commercial OS out there) has bugs (tons of 'em), but
for every PC that crashes probably only 1 in 1000 if not 10000 does so due to
an OS bug rather than an application or 3rd-party driver bug.

Don't forget about bad hardware. How much of the price of the
oscilloscope goes into the PC hardware? I suppose not much. Windows by
itself is rock solid if you run it on the proper hardware + drivers
and don't connect it to the internet.
 
J

Joel Kolstad

JeffM said:

I don't think you quite got my points. They were:

* Although there are plenty of "zero day" exploits for Windows and its various
applications, the vast majority of infections are still due to people clicking
executing some file they shouldn't.
* If you're going to let people like that use your scopes, well... I'd be a
little bit more worried about their *PCs* being infected and their *design
files* getting trashed than the scope's OS getting hosed and having to
re-install its brains.
* An easy solution to the 'scope problem is to just unplug it from the network
anyway and transfer data using USB memory sticks (although those could be
infected too...)

This isn't being blind to a problem, it's prioritizing the problem in the
grand scheme of things and taking actions appropriately. Indeed, in reference
to your article, it's all about trying to prevent unintended consequences by
considering what the "worst case scenario" is before it happens: Having a
scope lose its mind is far less "deadly" to your business than having your
engineers lose their design files.

---Joel
 
R

Rocky

Nico said:
Don't forget about bad hardware. How much of the price of the
oscilloscope goes into the PC hardware? I suppose not much. Windows by
itself is rock solid if you run it on the proper hardware + drivers
and don't connect it to the internet.

We had an issue with WinNT that 'Blue Screened' about 5 times during
install, required rebooting every day - until we replaced the hardware.
--Rocky
 
M

Mike Monett

Joel Kolstad said:
This isn't being blind to a problem, it's prioritizing the problem
in the grand scheme of things and taking actions appropriately.
Indeed, in reference to your article, it's all about trying to
prevent unintended consequences by considering what the "worst
case scenario" is before it happens: Having a scope lose its mind
is far less "deadly" to your business than having your engineers
lose their design files.

Ha! I have a slave drive connected at all times, so backup of the
entire partition is a simple XCOPY32. I keep the partitions at about
2050 megs to stay compatible with DOS, and a complete backup only
takes a few seconds. So I do it quite often, and have no problems
when Windows decides to trash the drive, or I download something I
shouldn't have:).

As far as a scope losing its mind, that is completely unacceptable.

That is another reason for making your own equipment. Then you can
run critical applications in DOS on some older computer that won't
even run XP:)

Regards,

Mike Monett

Antiviral, Antibacterial Silver Solution:
http://silversol.freewebpage.org/index.htm
SPICE Analysis of Crystal Oscillators:
http://silversol.freewebpage.org/spice/xtal/clapp.htm
Noise-Rejecting Wideband Sampler:
http://www3.sympatico.ca/add.automation/sampler/intro.htm
 
C

CBFalconer

Rocky said:
Nico Coesel wrote:
.... snip about scopes running under Windoze ...
We had an issue with WinNT that 'Blue Screened' about 5 times
during install, required rebooting every day - until we replaced
the hardware.

Microsoft has only itself to blame for much of that. It has
encouraged the 'cheap' machine without ECC protection (saving maybe
$25 per machine). Note that even the original PC had parity
protection for memory errors.
 
S

Stef

In comp.arch.embedded,
Mike Monett said:
Ha! I have a slave drive connected at all times, so backup of the
entire partition is a simple XCOPY32. I keep the partitions at about
2050 megs to stay compatible with DOS, and a complete backup only
takes a few seconds. So I do it quite often, and have no problems
when Windows decides to trash the drive, or I download something I
shouldn't have:).

And what prevents windows or the something that you should not have
downloaded from trashing your slave drive? And then there's other
simple things like failing powersupplies that take out all your
drives, fires...
Backups should be on removable storage that is kept in a separate
place, preferably in another building. And you should have at least
2 backups to prevent from complete dataloss during backup.
As far as a scope losing its mind, that is completely unacceptable.

Yes, that is completely unacceptable. But what is the damage when it
does? You reset it, set it up again and capture the signal again.
Mostly only a few minutes work (except when it takes a long time to
find the (un)desired signal condition).

On the other hand, a crashing PC seems sort of accepted although the
damage is usually much larger (lost files etc.).
 
M

Mike Monett

And what prevents windows or the something that you should not
have downloaded from trashing your slave drive? And then there's
other simple things like failing powersupplies that take out all
your drives, fires.
Backups should be on removable storage that is kept in a separate
place, preferably in another building. And you should have at
least 2 backups to prevent from complete dataloss during backup.

I do have multiple backups for just that reason. In fact, I recently
did something really stupid and had to go back 3 levels to recover.

I leave the cover off the computer, and set the slave drive on top
of the power supply. So it's very easy to change the backup drive,
which means it's easy to keep the backups updated.

This is a far cry from times I had to use Laplink on Win 3.11 and
spent days recovering from system crashes.
Yes, that is completely unacceptable. But what is the damage when
it does? You reset it, set it up again and capture the signal
again. Mostly only a few minutes work (except when it takes a long
time to find the (un)desired signal condition).

The time lost is not recoverable. The damage is unacceptable when
you can make your own system and eliminate the crashes.
On the other hand, a crashing PC seems sort of accepted although
the damage is usually much larger (lost files etc.).

The solution is simple. Eliminate the fundamental problem and move
to Linux. I have spent time in labs where Windows XP crashed several
times per day. Sitting right beside it was another computer running
Linux.

It never crashed.

I have had the same experience with my own computers. Windows would
crash regularly, but I would have Eagle running on Linux for 6
months continuously, and it never even hiccuped.

Obviously, when you are only used to using Windows, that's the level
you accept. When you have seen other systems perform flawlessly,
that becomes your standard for performance.

Windows simply doesn't come up to that standard, and it never will.

Regards,

Mike Monett

Antiviral, Antibacterial Silver Solution:
http://silversol.freewebpage.org/index.htm
SPICE Analysis of Crystal Oscillators:
http://silversol.freewebpage.org/spice/xtal/clapp.htm
Noise-Rejecting Wideband Sampler:
http://www3.sympatico.ca/add.automation/sampler/intro.htm
 
S

Stef

In comp.arch.embedded,
Mike Monett said:
I do have multiple backups for just that reason. In fact, I recently
did something really stupid and had to go back 3 levels to recover.

I leave the cover off the computer, and set the slave drive on top
of the power supply. So it's very easy to change the backup drive,
which means it's easy to keep the backups updated.

You are balancing a hardrive on top of an open case? Fine for testing
purposes, but not a long term solution. Even only leaving the case off
from your working machine introduces additional risks. There are other
solutions out there, like drive sleds and external drives. But I do
favour tapes for backup purposes. We also copy our data to other sites
through ssh tunnels as additional backup.
This is a far cry from times I had to use Laplink on Win 3.11 and
spent days recovering from system crashes.

Why didn't you uses the extra harddisk on W3.11? This solution does not
require any software and is OS independant and fast.

The time lost is not recoverable. The damage is unacceptable when
you can make your own system and eliminate the crashes.

True, but as stated this loss is usually much smaller than what is lost
in the average PC crash.
The solution is simple. Eliminate the fundamental problem and move
to Linux. I have spent time in labs where Windows XP crashed several
times per day. Sitting right beside it was another computer running
Linux.

It never crashed.

I have had the same experience with my own computers. Windows would
crash regularly, but I would have Eagle running on Linux for 6
months continuously, and it never even hiccuped.

I use Linux exclusively on 2 of my 3 PC's and the 3th is triple-boot
W98/W2000/Fedora Core. On this PC I mostly run W2000 and I can't
remember the last time it completely crashed. It's on 24/7 but it
sometimes needs a reboot. I am not a windows fan, and I would gladly
switch to linux only if I could, but windows has improved a lot since
W3.1.

But leaving eagle running for 6 months does not sound like good
practice either. It doesn't hurt to sometimes close your program or
even perform a scheduled reboot of the machine. Leaving it running
for 6 months also means you did not update your kernel for that time
either, not good if the machine is connected to the internet.

Obviously, when you are only used to using Windows, that's the level
you accept. When you have seen other systems perform flawlessly,
that becomes your standard for performance.

Windows simply doesn't come up to that standard, and it never will.

Most people use windows only and indeed accept things from their PC that
an engineer would not accept from his analyzer. And that was the point I
was trying to make: The average loss from an analyzer crash is smaller
than that of a PC crash, but the PC crash is more accepted than the
analyzer crash, weird.
 
C

CBFalconer

Mike said:
.... snip ...



The time lost is not recoverable. The damage is unacceptable when
you can make your own system and eliminate the crashes.

Is xnews causing that right justification and indentation? If you
can, please inhibit it. It makes further reformatting very
awkward.
 
J

Jan Panteltje

But leaving eagle running for 6 months does not sound like good
practice either. It doesn't hurt to sometimes close your program or
even perform a scheduled reboot of the machine.

Maybe for MS products?
Leaving it running
for 6 months also means you did not update your kernel for that time
either, not good if the machine is connected to the internet.

That is strange.
'Kernel upgrade becomes a bit of a religion no?
Well I recompiled kernel with new drivers in the weekend, but to
upgrade it I have had so much shit, it is the LAST thing I am looking
for, maybe when a new system.
Security comes from firewall mainly, and all the other strange
things one perhaps runs.
Yes I know about some security fixes in later kernels then I have.
Nevertheless I run a server, and have 562 entries in iptables to
keep the bad guys out now, read the server logs every morning!
For the rest zero problems

Also, as to backup, I have scripts that only backup to memory stick the
last code I wrote, saves space and time.
Have used this to port all scripts and apps I wrote to new systems.
To back up the whole disk or system may seem smart... but is it really?
As to that, I have a full backup system, with an older kernel version,
on a second disk.
If the server goes off (power failure for example), it will automatically
reboot in the backup system (because maybe there is nobody around to fix
things in the middle of the night), and it alerts me remotely.
As for MS Windows, I dunno, do not use it, do not need it normally,
except for some equipment I have here that has no Linux drivers or soft
and I am to lazy to write the drivers myself (or no manufacturer data).
Over the weekend I installed some other piece of hardware, the soft that
came with it for MS Windows did not work, and crashed, I compiled the
related modules in Linux and it ran OK first time, no reboots needed...
I really have pity for those who must use MS software, on a scope I
would burn the thing :)
Yuk, no sources, cannot even add functionality.
 
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