Transmitter hunting (also known as T-hunting, fox hunting, bunny hunting, and bunny chasing), is an activity wherein participants use radio direction finding techniques to locate one or more radio transmitters hidden within a designated search area. This activity is most popular among amateur radio enthusiasts, and one organized sport variation is known as amateur radio direction finding.
For additional info visit these links.
http://homingin.com/equipment.
http://www.barriearc.com/Fox_
http://www.orlandofoxhunt.com/
http://theleggios.net/wb2hol/
http://www.qsl.net/na0pw/
http://www.k3dn.org/foxhunt.