I just got one of these things for $1 at a flea market. It actually works pretty well as a wireless sensor detector of sorts, but the range sucks, only working to about 20 feet. Is there some way to boost the antenna with some sort of addon for this so that it'll operate at a much farther distance?

The trip sensor on the device is infrared, but then it sends a radio signal towards the main unit. It's that radio signal that I want to boost so that it'll have a longer range. Here's a manual of the thing describing it in more detail.

http://www.wildplanet.com/helpcenter/instructions/SpyTrackerSystem.pdf