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The length of the run is about 9km(7miles) for males over 18, and 6-7km(4-4.5 miles) for females and juniors (males and females under 18) and designed to take about an hour, an hour and a half to complete the search.

The goal is to find five(for males over 18) hidden radio transmitters-foxes in a shortest time. (Four for females and males under 18) Foxes don't move during the competition. Foxes are not shown on the map with which the competitor is equipped. Same type of contour/topographical map as used in the orienteering. Map allow one to derive the progression of finding by drawing the directions on it. They must be at least 400m from each other and at least 750m from the start point. Start point must be in the distance of at least 400 meter from the finish(Usually ~2km). Start and finish are the only two location which are shown on the map.


Foxes transmits the verbal depending on it's identity.  
Fox #1 call sign KG4DWJ-1
Fox #2 call sign KG4DWJ-2
Fox #5 call sign KG4DWJ-6

Foxes transmit respective signals in cycles of five minutes 1st minute fox #1 2nd minute fox #2 ... 5th minute fox #5 6th minute fox #1 7th minute fox #2 ...

There are two frequency ranges of operation. Each of the transmitters have fixed frequencies. For example fox #1 can be at 3.5200, fox #2 - 3.6450, fox #3 - 3.5700, ... similar in 144-146 range. 144-146 Mg hertz <-> 2 meter 3.5-3.65 Mg hertz <-> 80 meters


Competitor has a specially designed radio receiver. Weighted about 1-3 pounds.
(Hand made, World class, receivers can be obtained from various sources.

For 144-146 Mg hertz, dipole antenna

      | |
      | |

for 3.5-3.65 Mg hertz, used loop antenna combined with a stick antenna | | (( )) | | |_|


Armed with the radio receiver competitor can get the direction of where the fox is located by the level of received signal.

In following way: 3.5-3.65 range the shape of the signal is in the form of 8 and by activating the | antenna it becomes of the shape of apple in 2D. By looking at apple you can understand why it's not used for presize direction locating. - it's not too sharp.

Although in 144-146 range the shape of signal looks like a sharp apple and it's enough to give a good sense of direction.

It's very difficult to choose the right enumeration for the foxes search (it's not 1-2-3-4-5). One chooses the shortest path to the finish visiting all the foxes. 3-1-4-2-5 for example. Finding the first fox is the most difficult because one doesn't know very well how far foxes are located, because foxes can have slightly different power of transmitted signal, and so it's difficult to determine which one is closer. Once participant was in two locations he can estimate where the foxes are hidden. And decide which finding order to choose. Estimation - intersecting two(more for more precision) peelings (directions) from different locations.