I'll soon be buying a digital storage oscilloscope. I've used several conventional DSO's including some of the older CRT HP units, and the newer LCD tektronix units. However there are some relatively feature rich computer based scopes (such as those from pico) with added features like frequency counters and spectrum analysers and quite attractive prices also. The question is, how many of you guys have had chance to use computer based oscilloscopes and would you recommend a computer based scope over a conventional type? The Instek GDS-820 DSO has caught my eye at the moment, as has the PicoScope 3000 Series PC Oscilloscope. Thanks in advance for any assistance.
I still like my old analogs, but I do primarily audio stuff. I have stated looking into a DSO as well and I think I'm swaying the was of the pc based versions. They can do, as you mentioned, things that a regular dso just cant do i.e. spectrum analysis, distortion analysis, and lots more. Based on what you're planning on using it for would determine the dit count and sampling frequency of the D/A converter, which is where all the money is. Beyond that, once the signal is digitized, i cant see how a standalone dso can have the computational power of even a somewhat out dated pc let alone a good one. If your'e looking for a scope or spectrum analysis in the Ghz range, I dont think that pc based equipment has gotten that fast yet, atleast with some sort of descent bit count. But there seems to be quite a lot out there that has good accuracy in the audio range. However I haven't looked into them in about half a year so my info may be outdated by now. I'm not claiming to be an expert, I'm just sharing what I've learned so far as well as my opinions. I hope this sheds a little bit of light.
A couple of things to mention: PC based equipement is not really any less than stand-alone equipement. Just to clarify, most high-end HP digital scopes are computers already. They just have a built-in 4" TFT in the front of the case. It really depends on quality and cost. I would personally like to find an older digital scope (for cheap) that has an RS-232 interface to analize the analog signals. As for my experience, I had the pleasure to work with the newer HP models which were basically custom PCs. These were nice, but cost more than a Mercedes. I did once use one of those PCI cards in a plain beige computer, but its had like 10MHz capacity and was really poor quality (it was a while back, so I cant compare to whats available today). I imagine the quality has gotten much better. My advice: Pick your rpice range, and then consider the spec range differences.
Sorry for the slight hijack, but has anyone had any experience building a basic PC-based oscilloscope, either LPT/USB/RS232 based, or sound card based?
Is it possible to make a PC-based oscilloscope out of a PCI video capture card? No, but sometimes mabie If your card reads in baseband component video (svideo/RGB), and processes it using the CPU (if the card processes you'll loose everything that would happen during h/vsync), then you might get a yes, for everything else it's a no.
Just a general question. Wouldn't using an audio card for Oscope input limit the frequency range to that of audio? 20 to 20K Hz? john - really old EE with only analog scope experience.
Hmm, four year old thread, probably safe for me to stick my oar in here... I used a Picoscope in school and it was nothing but pain, the software was appalling but that was 8 years ago. Much more recently I used a Tektronix DSO and hooked it up to a computer with RS232 though all that gave was a static image of the screen, useful for including in reports but not much else. It did do Fast Fourier transforms though which gave it a limited spectrum analysis ability. I would be supprised if more modern DSOs didnt have the option to be controlled by the computer interface, they are expensive though. Yes a sound card based 'scope would be limited to audio frequencies though I expect even that would be pretty useful, especially given the very low price. Moriquendi
