VOR Navigation
The VOR RX and VOR TX apps were introduced in #3244. These apps allow decoding and encoding of VOR data.
What is VOR
A very high frequency omnidirectional range station (VOR) is a type of short-range VHF radio navigation system for aircraft, enabling aircraft with a VOR receiver to determine the azimuth (also called radial), referenced to magnetic north, from the aircraft to or from fixed VOR ground radio beacons.
It is essentially a primitive way to navigate through waypoints, where the user enters the heading to navigate on and the VOR and the instrument tells how far the aircraft is from that route.
Before using these apps, I suggest watching the following videos which are very informative:
- VOR Explained Simply by FlightInsight (recommended for beginners)
- How to navigate using VOR by FlightInsight
VOR RX app
This app allows you to tune to the frequency of a VOR and decode its signal, which provides your heading relative to the VOR station.
Values
- Status (read): displays whether the app is actively searching for VOR data or idle. Status can be changed by pressing the Start or Stop button at the bottom of the interface.
- VOR Band (read): the typical range for VOR beacons
- Decoder (read): the status of the VOR decoder, either:
- Searching: no VOR signal has been found yet
- Locked: VOR signal is steady and valid data is being decoded
- Course (OBS) (write): Omni Bearing Selector - the heading the user wants to navigate to (target)
- Received Radial (read): the receiver's radial as seen from the VOR beacon (the bearing to reach the VOR)
- Flag (read): if the instrument is navigating TO or FROM the VOR. There's a dead zone where the instrument will display --- and it is displayed when the user is within the dead band between the TO and FROM directions.
- See the video above to better understand this flag
- Calibration (write): this field allows manual compensation of the decoder algorithm, useful if you're using devices that might alter the phase of the received signals (like external filters or different firmwares).
- Course Deviation Indicator (read): this gauge shows how far off you are from the selected OBS. The center of the instrument is 0° meaning you're on the exact route, each tick to the left or right indicates a 5° offset from the selected course. Scale ranges from -10° to +10°.
- LOG to SD Card (write): allows the user to collect diagnostic information for manual processing (records the heading, obs, status, and timestamp)
Usage
- Tune the VOR frequency of the nearest airport (e.g: 115.800MHz for VRN airport)
- If the correct frequency was tuned and the VOR is within range, you should hear the Morse identifier of the VOR every 10 seconds.
- Set the OBS to the course you want to navigate (e.g: 050°)
- Observe the received radial and navigate accordingly
VOR TX app
Warning
Disturbing the air band is one of the most illegal things you could do. This is not a joke - you can get into serious legal trouble very quickly.
Neither the developers, the Mayhem team, nor anyone else except you is responsible for any fines, imprisonment, or other consequences resulting from interfering with aircraft communications, air navigation, or any other radio service while using this app. You alone are responsible for how you use this app.
This app emulates a VOR by transmitting a user-programmable heading signal together with an optional user-programmable Morse identifier.
Values
- Radial (write): the radial that should be transmitted
- Please note: the value can be changed at any time but the changes takes effect only after the transmission is restarted. To transmit a new radial, the user must stop and then start the transmission.
- CW Identifier (write): enables the Morse code transmission that identifies the VOR
- Ident (write): the string (7 characters at most) to be transmitted as VOR identifier
- Status (read): the current status of the app, either Idle or TX radial XX where XX is the radial selected before enabling the transmission
The bottom part of the application controls the transmitter settings, such as the frequency to use, the frequency step and the TX gain. To start and stop the transmitter, use the Start or Stop buttons. Before starting any transmission, a dialog is displayed informing the user that this app should only be used in a lab environment while transmitting into a dummy load.