I recently purchased, for a completely non-amateur purpose, a Gemini i-key USB recording device.
It now occurs to me how useful this could be for recording your satellite activity
Basically it is an audio interface that digitizes at 44khz, and stores the digital audio as an MP3 or more importantly, as a WAV file, onto more or less any USB pen drive.
With a set of 2100mAh NiMh cells, it will record about 4 hours of audio, onto your pen drive, so you can just plug it into your PC, and there ya go!, your last 4 hours of activity.
Plenty on Ebay, specs at >> http://www.ikey-audio.com/