| 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
ECT
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
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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.
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