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Rebel
Apr23-03, 07:56 PM
Any one ever use a sound card + software as an oscillscope?
I just want to know how i can make a probe to use as an oscillscope probe that can be plugged into the Input of a sound card.

Thanks

emu
Apr23-03, 09:40 PM
For audio frequencies, the probe from a multimeter will be fine. That is to say, a piece of wire will do. However, at radio frequencies, you would require a good oscilloscope with some decent probes. But for a sound card and some software, 2 wires will be sufficient.

BoulderHead
Apr23-03, 10:11 PM
emu,
I haven't seen a sound card thingy before, but I have seen special made PCI cards that come with all the needed cables/probes to take measurements with. The problem I have with those things is that they still cost you hundreds and hundreds of dollars, at least the ones I saw ($300 U.S. and up). For that kind of money I'd rather spend a few hundred more and get a stand alone unit.

Rebel
Apr23-03, 11:05 PM
Yeah thatnks that is what i figured is that i can use just wires

emu
Apr24-03, 12:16 PM
When I was 16, I managed to salvage a nice B&K oscilloscope, good to about 20 MHz. It's a pain in the *** to lug around but when I need it, it's the only tool I trust. I've tried some software for use with soundcards using the line-in as a scope but there are limitations.
I use mine mostly for audio testing, and often for bass frequencies. I doubt a sound car will read flat down to about 10 Hz while a good scope will.

What are you going to use it for?

Rebel
Apr24-03, 02:27 PM
Im going to use it for mainly audio purposes. So i can repair audio equipment and design audio as well.

emu
Apr25-03, 04:01 PM
If you have an old pentium 133 or something low-level with a soundcard, use that as your test machine. You can afford to fry the soundcard a few times while learning. However, be careful using this scope to repair active components. I don't even know what kind of voltage a soundcard can endure. I'd imagine the input impedance is the standard 10K so keep that in mind. A scope is in the Megaohm range.

BoulderHead
Apr25-03, 04:13 PM
Where might I download a trial version of the 'sound-card software' so as to experiment with it?

Rebel
Apr25-03, 04:44 PM
I download a program called WinScope but there are plenty of oscilloscope programs out there that use your sound card and a computer. Most I've seen are either freeware or shareware. But i havent tested any of the programs yet so i dont know how good they are but im going to eventually go out and purchase a scope.

BoulderHead
Apr25-03, 11:59 PM
Thank you for the tip Rebel. They even have a 16-bit version, which is right up my experimental alley. Check it out here;

http://polly.phys.msu.su/~zeld/oscill.html

megashawn
Apr26-03, 03:56 PM
Just to add in that Mandrake Linux (and probably other distribs) come with it as an option to install. Would be nice to get a decent O scope for less then $1000.

Rebel
Apr26-03, 06:21 PM
It would but that damn scopes are so expensive.

grady
Apr26-03, 11:36 PM
I got an O-scope about a month ago from www.testequipmentdepot.com. It does everything I need for my piddling and the price wasn't too bad. http://www.testequipmentdepot.com/instek/oscilloscopes/gos-620.htm

What I don't get is why protoboards are so expensive. :( Mine burned up last night right when I'm trying to work on my final project for instrumentation class too. It was very old.