These little ebay 2$ USB sticks give real audio input on the raspberry Pi:
Little test script:
#/usr/local/sbin/record_audio
if [ "$1" == "" ] then echo "Usage: record_audio filename.wav" echo "This will set environment variable AUDIODEV=plughw:1,0 for the USB stick."
exit 1 fi
export AUDIODEV=plughw:1,0
rec $1
exit 0
###### To play it back via same USB stick (watch your ears, volume if way to high for earphones): play whatever.wav
You probably want to set the environment AUDIODEV back to normal...
I used line level audio in from mp3 player to test. This also means we have 16 bit stereo for data acquisition. USB sticks took > 1 month to arrive from ebay..
And 'soundmodem' (AX25) now has real input on the Raspberry. Too bad I already worked around it 3 weeks ago :-)