Osciloskope

[labtec1]

Hello everyone
Do any of you have tried it through the PC sound card oscilloscope make? To purchase an oscilloscope to set aside that amount of money so for our purposes I think this was sufficient
I'm sorry my English is terrible
thanks for ideas and answers

[Davor]

Yes, I use PC soundcard as an oscilloscope. I use "Visual Analyser". It is a bit difficult to start using because of many odd menus, but once you get through it is fine. You can calibrate it to a known source,

You will not be able to use it with PI rigs though.

[Krzysztof]

Hi Labtec1.
See the network USB oscilloscope; much faster, memory and FFT.
See ebay, the prices are different.
Best regards Chris.

[labtec1]

thanks for answers
ebaj to have very interesting things but I'm from Serbia and I wonder if you'd say buy a $ 50 oscilloscope how much it would cost in Serbia and how they are delivered

[6666]

Davor
what are you useing as a probe for the sound card ?
thanks

[Davor]

Something like this...

[6666]

Hi Davor
thanks , it has no protection diodes, are they not needed for sound card ?

[labtec1]

I think it's best to insert an old sound card in the PC costing 1e around anyway, so what is one to be - there will be a shame if something goes wrong

[Davor]

Protection diodes are not needed if you power your rig with batteries. You simply can't produce voltages nearly high to do any damage. That is actually the only caveat. Real laboratory instruments have carefully designed power supplies that float. You can't expect a piece of consumer electronics such as PC to be as good, so make sure your device under test is floating instead - power it with batteries.

You can put antiparallel diodes in parallel with a 470ohm resistor if it makes you feel better.

To do any meaningful measurements in ~10mV range, you'll have to connect your PC sound card directly. In that case make sure you actually have a low impedance to hook it to, and that you do not expect much more than 100mV there. The best example is hooking the PC to a 1k resistor at the output of a preamp in order to fine tune the coil balance. First you establish a coarse minimum to get below 100mV using a 1:10 probe, and only then you hook it directly, and with no 470ohm resistor. See example:

[mohandes]

hi davor
an you put for me the oscilloscope software for the computers,i have Cool Edit Pro 2.1 but it dosent good.
thanks

[Davor]

So far the easiest to use that I'm aware of is found here: http://www.zeitnitz.de/Christian/scope_en
It has some off licensing, but it works fine.
The above mentioned Visual Analyser works fine as well but it is a bit confusing.
Results will depend upon your soundcard quality, and you can not expect super accuracy even after you calibrate these, but for the relative measurements both will be just fine.

[Davor]

Ah! In case you wanted to use any of these to do any measurements a PI front end, just forget about it - too slow.

[mohandes]

thanks Davor
ok i download now and run it to test it.
i need the lincense kode?do you have

[Davor]

No I don't, but it works as is.

[BKY1337]

Im interested in a picture of your soundcard oscilloscope when a coil is connected.
Do you have one? Or can you tell me how it looked like?

Mine looked like spikes because of the poor resolution.