Have you used a PC-based Oscilloscope?

[Ironbar]

I'm going to buy a scope.  It's time I owned one.

Do a search on eBay for 'oscilloscope' and look at the pc-based ones, like the DSO-2150.

Having only used Tektronix and HP 'real' scopes in the past, a PC-based one seems very intriguing to me - not to mention affordable.

Do any of you have any experience with such PC-based Oscilloscopes?  Do they work to your satisfaction if so?

Thanks!

 

[rog8811]

I will look to see if I can find the thread where I posted a link to a free download of the one I have....watch this space

Regards rog8811

 

[phoenix3200]

I've been looking into scopes on eBay for the last two weeks or so and ended up purchasing an antiquated digital oscilloscope that I hope works. My only comment is to watch out for the sampling rate. Many of the ones sold online are no better than finding a 192kHz sound card and using it for your ADC.

The DSO-2150 looks fine to me - I have no idea about it's build quality or the software, but it is a 60MHz / 150MS/s scope.

 

[rog8811]

Found it http://www.laserpointerforums.com/forums/YaBB.pl?num=1199369106/6#6
Read the thread, this has all the bells and whistles I need, the only thing I have changed since that thread is to increase the number of diodes in the probe adaptor board to match with my sound card.

Regards rog8811

 

[Ironbar]

That's absolutely fascinating Rog - I've read a little bit about audio card oscilloscope adaptations, but I guess I ruled them out due to perceived limitations.

From what I understand, frequency response is limited to the audio range, and DC levels cannot be measured. What sort of bandwidth do you get on that thing, and can you measure DC levels?

I guess I could play around with it - the initial expense looks pretty darn low, I might have the components on hand even.
And I've got plenty of PC hardware to mess with.

 

[Ironbar]

Oh boy, this looks like fun - I did a quick search in FreeBSD's ports collection, and came up with xoscope.

You can find it at xoscope dot sourceforge dot net -- check out the hardware buffer he built!

 

[rog8811]

I will admit to having trouble with DC levels but just assumed that it was something I was doing, I used it for looking at TTL switching for my scanner, it worked fine for that and I was able to sort my problems out.

As you say the price is right and it is worth downloading just to see what it is capable of.

Regards rog8811

 

[phoenix3200]

I think (and am most likely wrong) that sound cards get their inputs by using differential voltage sensing and then integrating it to come up with the resultant waveform. If you wanted to, you could probably attach a multimeter in parallel with the circuit to get the DC offset.

 

[Ironbar]

This sounds like a fun project - but I'm going to try a DSO-2150 first. I've got a couple hundred bucks burnin' a hole in my pocket.

 

[Bionic-Badger]

Let us know how it is. They're a bit expensive, but cheap compared to other oscilloscopes with those specs--if it lives up to them.

 

[billg519]

I have a DSO-2090 (40mhz 100MS/s) I use it with my laptop. The software installed to XP Pro no problem, and this device has worked reliably so far. I've had it nearly a year now. Small, fits easily in the laptop case, powers off the usb port, has a 2v pp 1khz square wave calibration output. It came with two probes that are half decent.

 

[Benm]

They are quite different from analog scopes though, especially when comparing specs. A 10 MHz rated analog scope is likely to outperform a 100 MS/s digital one on fast signals. Amplitude might be way off for the analog one in that case, but you can still see what's going one to some degree.

The cheaper digital scopes are great space savers though - on the go, analog scopes will break your back.