BleepingComputer.com: Recording Silence

My friend is in Europe, and while he is gone, I figured I might do something to explain what happened while he was gone.

We both enjoy listening to our Police Scanners, as we both wish to be Officers one day, so I thought while he was gone, I could just plug in my scanner (to the wall so I don't waste batteries, and to the computer so I can record it). I am using Total Recorder, only because I have seen it working and NOT record the silence from recordings. But my scanner seems to have a VERY minimal constant sound output from the actual scanning itself. I wish to find a program, or a solution to the one I'm using now.

There are some things that aren't really an option, like dealing with the silence, and then using an Audio Editor to remove the silence later, but 1, I don't want to do that, and 2, my program, Adobe Audition, doesn't work with Windows Vista.

The first thing I want to do is try and find a different program that will only record when something is loud enough, so I can filter out the "silence". Sure the transmissions will be all together and when they say the time, it will sound odd because a whole hour could go by without anyone saying anything (no more than an hour... ever) and then you jump ahead an hour, but it's better than HUGE audio files on my computer and my friend having to listen to an hour of silence. So just something that can record from Line In, and have some sort of filter type thing for the "silence".

Thanks.