In the most general sense mean definition of the direction on an object which exact location is required to be found by direction finding. For these purposes use various direction finders which can be the simple mechanical devices operating by the principle of a compass or more difficult electronic devices which operation is based on distribution of radio waves.
Pelengovaniye in navigation
At stay in the sea the vessels often should maneuver not to encounter islands, banks and other obstacles. Navigation signs which are applied on pilot charts not always happen enough. Use of a direction finder is considered more reliable way to establish exact location of the vessel and the obstacles hindering its movement.
The simplest direction finder represents the disk consisting of a viewfinder and a washer with the angular divisions applied on it. By means of such simple device it is possible to carry out a pelengovaniye of two reference points. To take a bearing on an object, for example, on the lighthouse, it is required to put a compass card of a direction finder in compliance with a compass compass card that each of them pointed north. Now it is necessary to define by means of a vizirny part the direction on the necessary object, that is to take a bearing.
Then the same method is used for definition of a bearing on the second visible object – the high rock, a dome of church cathedral and so on. On the sea chart taking into account the revealed angular directions two lines passing through the planned objects are drawn. The location of the vessel will be defined at the same time as a point of intersection of these lines. Usually for a pelengovaniye at the sea the special compass which is specially intended for these purposes is used. But in the conditions of insufficient visibility today radio direction finding is most often applied to a pelengovaniye.
As the radio direction finder works
The radio direction finder is good the fact that it can be applied both at the sea, and on the land in the conditions of limited visibility and illumination. Operation of such device is based on the principles described above, the difference exists only in technologies. To zapelengovat the victim's radio beacon air crash or, let us assume, the enemy transmitter, the operator deploys the direction finder antenna so that the radio signal was most expressed. This direction is displayed on the indicator device and designated on the card by a straight line. Now the mobile direction finder changes the place of the arrangement, being removed aside. In the new place the following bearing is removed, that is the direction in which the radio signal will be the cleanest and accurate is defined. Now it is necessary to draw on the card the second line in this direction. Crossing of two lines will give a point in which there is a required sending device. The method of radio direction finding can be used with success in military science for detection of means of a radio communication of the opponent and his command posts. But it can be applied with success and to detection of own location if at the disposal of the operator there is a card with applied on it with the radio beacons fixed on the area. To establish a point where there is a radio direction finder, it is possible just as by means of the ship disk device.