you hold the fob under your chin. It turns your body into a antenna. I was able to get between 200-300' of range. At friends old apartment which was on other side of another apartment from parking 2nd story i could hit panic and such and hear the horn.
If your worried there was a mod you can make a larger antenna and run it behind the dash.
I dont worry about this any more, I can get up to a mile range with mine now with 2way paging so.