A simple and easy USB soundcard hack for an Oscilloscope. The best use is together with an bread board.
But please be careful, no protection is build in. Input signals up to 5V should be save.

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Download xoscope-2.2.tar.gz from:
https://sourceforge.net/projects/xoscope/

 $ tar -xvf xoscope-2.2.tar.gz
 $ cd xoscope-2.2cd

one has to fix the package (at least for Arch Linux), remove the line 37 from display.c. Open:

 $ nano display.c

and remove:

 void    *font;

Install the package:

 $ ./configure
 $ make
 $ sudo make install

Download micoscope-linux-1.0.tar.gz from:
https://sourceforge.net/projects/micoscope/
Unpack it and run it:

 $ tar -xvf micoscope-linux-1.0.tar.gz
 $ cd micoscope-linux-1.0/MicOscope/
 $ ./MicOscope

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Use a cheap USB soundcard. Open the housing and solder a wire to the ground and the signal pin.

Close the housing, that's i!

Best use is together with a breadboard For an simple input protection a decoupling capacitor and a potentiometer to attenuate the signal would be useful, too.

                  Poti
 Signal __100nF___| | |______GND
                    |
                    |____Mic Input

If you want build a better protection circuit here is a simple one:
http://xoscope.sourceforge.net/hardware/hardware.html
One can use 1N4148 diodes instead of the 1N914 diodes.

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