Advice on Digital Oscilloscope Design

Pretty much, yeah. ;-P

Basically, getting one to trigger properly was black magick. Is that "user interface" or "fundamental performance"? ;-)

Cheers! Rich

Buy one s/h on Ebay !

Graham

I thought it was common knowledge that you buy scopes from Tek but analyzers from HP.

USAF.

Float they did. I remember a press release for same. Scope' was impressively photographed underwater and working, along with accompanying babe c/w snorkel. Casing straining against a lashing anchored to sea bed. john

And DVMs from Keithley.

John

Flat panel displays use fast ADCs as well. I would be very pleasantly surprised if someone hacked a panel into being a 3-channel scope :)

Another subject: if the input attenuaror settings are known to the display software, that software could remove input related distortion, couldn't it? Just calibrate and off you go (al long as there are no nulls...)

Thomas

Wasn't HP the one that had a scope or so with just a single twist knob on the front panel? Yikes.

I suppose that there was a poer switch and a way to click that wheel as well. But still...

Thomas

Nah. Electrometers and magnetometers, you get from Keithley. DVMs, you get from Fluke. :-)

Cheers! Rich

That is my experience, unless your budget can allow for a Lecroy scope, them is sweet

We have some of those at my workplace.

Impressive when in full flow, but I don't enjoy waiting for Windoze to load before I can do anything.

The handhelds, sure. But Fluke has abandoned the precision benchtop market... all they have is the ancient, mediocre 45 and some $7K or something "systems" box.

The Keithley 2000 is a work of art.

But this looks slick:

John

In article , Zak wrote: [...]

You'd have to have quite a bit more memory as you ever allow to be seen on the display, but that isn't a big problem these days.

It wouldn't even take much processing power since the correction is done after the data is gathered.

Nah, you buy the $3 ones from

When the battery goes dead, you throw away the meter and get out a new one.

But could you ever rely on the readings you obtained.

Crap in ---> Crap out

What analog bandwidth do you need?

Sampling rate and analog bandwidth are not the same thing. Fast digital is easy to do, particually with FPGA's and PLDs. High analog bandwidth front ends on the other hand are *not* easy to do. But even with a 100MHz sample rate there isn't much point having your analog bandwidth more than 10MHz, unless you'll mostly use your DSO for repetitive signal (and/or FFT) work. But then the consequence of doing repetitive sampling adds more complexity to the project again. If you don't know the difference between one-shot and repetitive sampling on a DSO then you probably out of your depth on this project.

The most important thing with a DSO that determines it's usability is the memory depth.

You mentioned in another thread you don't know what an FPGA is - you certainly have a BIG learning curve ahead of you.

You might like to check out some of my (very) old DSO projects for some basic ideas:

Dave :)

All you HP bashers have obviously not used the 54600 series or the newer 6000 series scopes. They have excellent usability, and have now surpassed Tek's IMHO. Yes, the pre-54600 series HP scopes were, umm, not very easy to use. I have well and truly jumped ship from Tek to HP now.

Lecroy are the kings of usability crypticness!

Dave :)

(about really cheap meters)

We bought 20 of them. They all work fine. You just don't get a lot of digits in the measurement. Its like my $6 wrist watch. It was fine just done confuse it with an atomic clock.