Many a slip
Always remember that your hunting equipment can only show you the direction of the strongest signal, it does not know where the hidden transmitter is!
No matter how 'state of the art' your DF equipment is, do not bank on your first readings taking you directly to the 'fox'.
If you never lose sight of this fact, then you will be half way to winning your first radio foxhunt.
Swing that beam!
Small handheld beams have a very broad response, so their point of maximum signal reception is ill defined. A common fault I have seen with many newcomers is that they don't swing their beam very far and so find it hard to detect the true peak in the signal. Swing your beam side to side over an arc of 180 degrees to start with, then 'home-in' once you have a feeling for the direction.
Average those readings!
When trying to get a bearing on the transmitter, you will be swinging your aerial side to side and listening for the strongest signal or watching your signal strength meter. It is a good idea to take a second or even third reading standing in different positions, mentally averaging the bearings.
The idea behind this technique is that on your first reading you may be standing in a signal 'null' and the signal will get stronger as you move the antenna away from the true bearing.
The simple action of taking a step to the left or right will eliminate this anomaly.
Height wins every time!
Another phenomenon that will give false direction readings is reflections. In built up areas or hilly terrain, signals will reflect off large objects and confuse your readings.
It is therefore a good idea to try to get above these objects by finding a convenient hill and taking a bearing from the top. Use the averaging technique mentioned earlier to be sure of a reliable result.
As you cover more of the map during the hunting season, make a mental note of useful high spots and their aspect. Better still mark them on your map, you never know when you might need them again!
'S' marks the spot!
The signal from the hidden transmitter will quadruple in power each time you halve the distance to it. In terms of decibels that is a 6dB increase, so you should be able to use this information to guesstimate the distance to the 'fox'.
Remember this technique is only valid for 'line of sight' transmissions, reflections and objects in the path will of course confuse matters.
Keeping an eye on how the signal strength behaves can in fact give clues to where the transmitter is hidden. A sudden loss of signal, may coincide with your going past a large building indicating that the transmitter must be behind it.
Similarly a sudden increase in signal, as you pass the building, could indicate that the signal is being reflected down to you off the structure, and so the transmitter is most likely situated on the opposite side of the road.
Always have an angle!
You will soon become familiar with triangulation techniques as your hunting skills develop. A simple technique for roughly determining the distance to the hidden transmitter is an adaptation of this idea. Assuming your route is fairly straight line, you take readings of the angle to the 'fox' until they are at 45 degrees to your heading. At this point note the reading on your mileage odometer (or reset your 'trip' meter). Travel on until the angle to the 'fox' has increased to 90 degrees and note the mileage reading. Simple geometry tells us that the fox will now be roughly this 'mileage reading' away, and at right angles to your vehicle.
I can't hear you!
What happens if you lose the signal altogether? Here is good tip to use to avoid getting lost when this happens.
Always keep a mental note of where the signals have been coming from with respect to your vehicle. Couple this information to some prominent landmark such as a large tree on the horizon, a cellular radio mast or even the Sun. The angle to this distant landmark will not change greatly as you move along, allowing you to effectively keep heading in the right direction until signals reappear.
Its good to talk!
If you are the navigator in a vehicle fitted with a roof mounted beam, keep your driver informed of the signal bearings and strength. Your driver needs to know in advance if he is likely to be making a turn. Give a running dialogue so all the occupants of the vehicle know what's going on, and can use this information to augment their spotting skills. This will leave your driver to concentrate on getting you there safely without any unwelcome surprises!
Don't give up!
It is very easy as a beginner to feel downhearted when you become confused or have trouble getting reliable readings. You may end up coming last or even have to be directed by radio to the 'finish'. Don't be disheartened, the only way to improve is to participate and gain valuable experience.
At the get together after the hunt, find out what readings other competitors got and if possible, from where. You may find they were just as confused as you, but relied on their experience and the tips above to get them through.
There is as much to be learned from listening to the chat after the hunt, as there is to be gained from hunting itself.
Beginners Only | Techniques
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