Has anyone used this sound card probe?

[E:pp:ik]

Virtins Sound Card Oscilloscope Probe

I want to use this probe with the Zeitnitz Software Scope. I tried out the ladyada version with with no success and while I'm all for the DIY approach, this is one of those tools that would just be good to have in the tool box ... without lugging around a 40 pound piece of hardware.

Any feedback would be great! Thanks!

[E:pp:ik]

Just wanted to mention that I picked one up and just used it today. It works really well (being a n00b at this of course). I ran into a brick wall with my VCF and got it properly tested with this today. I can't express how relieved I am. Any way, good soundcard probe in my opinion!

[adafruit]

These are wikkid cool looking and I'm going to see if I can carry them in the x0xsh0p
strongly encouraged to all, the 'DIY audio scope' in the x0x page is kinda lame but can usually be built with 'stuff from radio shack' which is what I was aiming for.

[E:pp:ik]

Hey ladyada! I'm honoured to see you jump in on my post. Let me take the moment to thank you for making this all happen! Thanks!

I gave the diy probe an honest effort, but I used stuff that was kicking around and wasn't getting the results I needed to test the x0x. I'm not knocking the radio shack ethos at all actually. I'm all for it. I just don't know know enough about it to get it right. I also didn't *really* want a hardware oscilloscope. A small footprint alternative was high my list so I started digging to see what I could find.

I've kept a Sound blaster Live Value! card installed on my comp alongside my daw cards. It's worth maybe $10 these days. I plugged the probe into the line input on that, fine tuned Scope, and it worked just fine.

[Paradigm X]

Zeitnitz Software Scope. I tried out the ladyada version with with no success... [snip]

I built the ladyada scope last night and tried this scope software and had no joy. Trouble is i don't know whether its the scope, the software or the x0x build.



Is there anything i can test to make sure the scope and software are working first? Bit of a chicken and egg (or two eggs!) situation at the moment.

All the voltage tests were correct, from the build manual - is this enough to continue?

Many thanks

Ben

edit - in case this wasnt clear, not criticising anyone or anything, its great such clear instructions are available to make a cheap and cheerful scope. ta.

edit2 - i guess i shoudl mention that another problem is that im not exactly sure how to use this software... i just put it on auto. I got some signal, which did appear to change in frequency (number of 'blips' on the screen) when i turned the trimpots or the pot. I need to have a proper look at it.

Cheers

[guest]

you can try sending it a signal from a known source
like the output of radio or another synth
and see if it captures the audio

if that doesnt work
just run the audio straight in without the probe
and see what happens

[Paradigm X]

OK;

Success! (I think)

i got this



Upside down but seems ok.

I tried swapping the leads on the SC scope probe as per the sc probe building page, and it worked!

It seems to backwards but i read a thread about that recently on here, will look for it now.

Does this look ok?

Edit... hmm, its saying Vp-p 1.76 v - shouldnt this be 5.5v?

Turning the knob on the probe just distorts it i think, makes it squarer. 3v going in.

Cheers

[guest]

that looks good

[Paradigm X]

thanks guest


i dont know if you saw my edit... its saying Vp-p 1.76 v - shouldnt this be 5.5v?

Turning the knob on the probe just distorts it i think, makes it squarer. 3v going in.

turning the trim pots, and the main tuning pot on the back changes the frequency so all good.

Thanks

[guest]

there are 2 main differences
between a sound card and an oscilliscope

the first is that there isnt a calibrated input voltage
on the sound card scope
so the levels are all relative

the second is that the sound card
has a limited frequency response
so it wont look exactly as it should
but will be fairly close for most audio things

[Paradigm X]

awesome, thanks as always.

So basically just looking for the right shape.

Im very excited about how this is all going!

[antto]

and there is another difference, most soundcards have a DC-filter (usually a 1st order HP filter with some low-ish frequency)
i did overcome this on my previous soundcard with a "reverse-HP" filter, strangely none of these software o-scopes have such feature
tho, even with this, the voltage reading wouldn't be precise, at least a square wave would look like a square wave

[Paradigm X]

Thanks antto!

Great to have such knowledgeable and helpful people on board.

I was a bit worried about building a x0x, but if you take it really slowly and check at every step its not too bad. And the very helpful people on here to help when you get a weird reading (i had a dodgy voltage regulator which was diagnosed and replaced).

Cheers