Fox Oring
Fox Oring is a variation of the radio orienteering.
...The term is derived from the use of the term fox hunting to describe recreational radio direction finding activity and an abbreviation of the word orienteering. It is necessary to discover 5 hidden transmitters located on a 10 × 10 field in as few moves as possible. The transmitters broadcast in all 8 directions, the number on the cell indicates the number of intersecting signals.