PC Oscilloscope

[Gus2412]

Hi!, i downloaded a program that simulates an oscilloscope with the sound card of my pc, Can i really use it as a real oscilloscope without damage my computer with the signal of 9v?

[moosapotamus]

Can you post a link?

Thanks
~ Charlie

[Gus2412]

I don't remember the link, but there are many programs.

The most complete is PS Digital Micro LAB 2.0 Audio Analyzer.
Other is BIP Oscilloscope 3.0
and the best for me is SB Oscillograph, i like this because it's very simple and easy to use.

You can search in Google. I found them there

[moosapotamus]

As long as you're audio signal (input) is not clipping, I would think your computer would be just fine and dandy. In fact, my guess is that you could blow your speakers before you would do any damage to your computer.

~ Charlie

[Fret Wire]

I'm curious about this. Does it just measure frequency response? Or could you use this for things like setting the trimpot on the phase 90 & 100? I know MXR use to set them on a scope instead of by ear. I take it you have to use the inputs/outputs on your soundcard for this?

[amz-fx]

Can you post a link?

There are a couple on my site at:

http://www.muzique.com/schem/tips.htm

regards, Jack

[Gus2412]

I don't know if you could use this for setting the trimpot on the phase 90 & 100, because i'm a begginer, but there are many oscilloscopes that are very functional, and maybe one of those could help you.

Some of the oscilloscopes can show you the spectogram also.

In order to use it, you have to build your own cable with a small plug that fits in the line input of your sound card, and a common point of a oscilloscope. Or also you can plug the output of your circuit to the line input of your sound card. I suggest the first option.

[toneman]

Hi DIYscopers,

Most(all?) PC(soundcard) scope programs are not DC-coupled.

Signal input *must* be AC only.

Lots of stompboxes use single 9V for PS.
This usually means making a "fake" gnd at half the supplyV.
In these cases, Gnd is not really Gnd.

Make sure U have a test waveform generator to verify operation.

staytuned
tone

[kroushl]

My experience with PC oscilloscope programs is that there is a lot of noise in the signal.  I'm supposing this is because of noise inside the computer.  Are there any ways to reduce the noise (such as a buffer or external usb soundcard)?

Also, does anyone have experience with the o-scopes that require a hardware interface?

(such as one of these)
http://www.picotech.com/index.html
http://www.bitscope.com/

Any pros/cons compared with a bench DSO?

Thanks,
Brad

[Gilles C]

Here is what I use when I do a quick check.

http://www.jhc-software.com/gtune.htm

The needle damping option permits to get rid of the noise inside your PC.

When I want to calibrate the voltage scale, I feed it with a standard signal like 1 volt and then then change the gain of the input card to match what I want to read for 1 volt.

This program is also very very useful to tune guitars.  :roll:

I like it so much that I registered it a while agao.

Gilles

[Gilles C]

Oh, I forgot, I didn't try it, but it sure looks good.

http://www.newfreeware.com/audio/1535/

[kroushl]

I have tried the Realtime Analyzer Light (RAL) and it has a lot of good features, probably the best pc analyzer I've tried out yet.  Still, there's the problem of noise.

Brad

[mattv]

Here is what I use when I do a quick check.

http://www.jhc-software.com/gtune.htm

Gilles

Hi Gilles! Are you using this with just a plain jane soundcard? I'll have to give it  a try.

[Gilles C]

My sound card? Well it's not exactly a plain one.

It's a Sound Blaster Audigy EX.

I wanted the external box to be able to plug my things without having to go under the desk to reach the back of the computer every time I needed to. It's suposed to have less noise also.

But I'm sure the result would be good with a standard sound card. You can try it without having to register the software, so you've got nothing to loose.

Gilles