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What Is A VHF Direction Finder?

What is a VHF direction finder? It is a radiodetermination process that is using radio waves reception to determine a specific direction of an object or a station. The radio direction finding itself is a general term that encompasses various apps using the same operating principle.


The definition you just read was introduced by ITU or the international telecommunication union. And then ICAO adopted the definition. Since VHF is the main civil aviation communication, the term VHF direction finder now becomes the most recognizable term among many aviation professionals.


Description About What Is A VHF Direction Finder?


The VDF or VHF direction finder is a ground-based radio aid. It consists of a VHF radio receiver and a directional antenna system. Both of them are tuned to an operating frequency of the services unit of air traffic.


When an aircraft is receiving a transmission, the VDF is going to provide the direction where the transmission came from. The stations of the VHF direction finder may work as an array or independently. In former cases, the stations only provide the transmitting station’s direction.


When at least two VDFs work together, the devices can offer position information. They can provide such information by calculating the bearings’ intersection point that was obtained from various receivers. The operation principle of direction finding isn’t limited to the use of VHF.


There is also a UDF or the UHF direction finder that is going to operate on UHF frequencies that were used by various state aircraft.


Applications of VHF Direction Finder


What is a VHF direction finder

Is it enough to learn only about what is a VHF direction finder? It is crucial to know how people use this direction finder device. Thus, you’ll understand the various applications of the device and show some more appreciation to the founder of this device.


1. Navigational assistance


The pilot is going to ask the ground station to provide a piece of bearing information. And then the pilot will get the magnetic bearing to (QDM) or the magnetic bearing from (QDR).


This is going to help them in determining the movement direction and position. Also, true bearings are available, but those true bearings are used less frequently.


2. VDF approach


This one is a non-precision approach. If there is information about aerodromes that are using the VHF direction-finding approach, the information will be published in national AIPs.


3. Homing


The pilot will request a series of QDMs so that he can go to the VDF station. The request is normally at intervals of around one minute during the homing initial stages. But the frequency will increase as the VDF is approached.


4. Unauthorized use of ATC frequency


Usually, law enforcement agencies will use the VDF equipment when they are trying to locate unauthorized transmissions source. This is another positive use of the VDF that only law enforcement agencies can do.


5. Enhance situational awareness


What is a VHF direction finder? And how can it help enhance situational awareness? Air traffic controller has been using VDF to enhance situational awareness for decades. Even though the device becomes a standalone tool, it can provide the idea of an aircraft’s specific position.


It can integrate with surveillance equipment so that both devices can indicate which target on the screen created the last transmission. When radar was famous and they used the plan position indicators, the radar display would flash a strobe of light in the direction of a target that represented the transmitting aircraft.


Modern systems are now using arrays of VHF radio direction finders that are going to indicate the approximate location on a situational display. This will not uniquely identify an aircraft, especially in a busy environment. However, it will draw the attention of the controller to a small airspace portion.


The Right Device from The Right Provider


Today, government and law enforcement agencies need to use sophisticated devices to help save people’s lives. They need to get those devices from the most reputable source and provider. SMS Broadcaster is the right provider that offers quality devices for governments.


Explore the official website of SMS Broadcaster and you’ll see the wonderful products you can get. Those devices come with excellent features that will help governments complete their job successfully. Once you’re done reading about what is a VHF direction finder?,get the device you need immediately.

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