Locating a transmitter

[atbrown]

I'm new to robotics, but managed to build the $50 robot using a breadboard and the 9v/4.8v battery combo.  I'm wondering if anyone knows the simplest way to upgrade the robot so that it has the ability to travel towards a transmitter.  My goal is to place a transmitter in a different room in my house and have the robot's receiver automatically find the transmitter while using it's sensors to avoid obstacles along the way.  Any ideas, comments, or suggestions?

Thanks.

[waltr]

Since no one has given you info I'll try.

The traditional method that works for locating a transmitter is by using a highly directional antenna on the receiver and get a bearing from two locations as widely separated as is practical. Then map the two bearing to 'triangulate' the transmitter's approximate local. Move closer and repeat until the transmitter is found.
http://www.google.com/search?q=transmitter+hunting&ie=utf-8&oe=utf-8&aq=t&rls=org.mozilla:en-US:official&client=firefox-a

This works reasonably well in the open but can cause difficulties inside due to reflects of the RF transmission. For a robot this might work to find the rough direction to travel. If you work at it you may even be able to have the bot zero in on the transmitter's exact location.

Another way that several people have used successfully but requires line-of-sight is with an IR LED encoded emitter and detector. This has been discussed a number of times on this forum.

[atbrown]

Sweet, thank you for replying.  I've tried a lot of different searches on Google for my answers, but never thought of using "Transmitter Hunting" before.  It shows a lot of good results; I'm sure I'll find what I need now.  Thanks again.