Which frequency does Vox pick?

[bmaik 11]

Hi to all,

Does anybody know how VoxATC decides which frequency to use if there are multiple options? For example, in reality many aiports have multiple approach frequencies and depending on the sector an aircraft approaches from, one of these will be assigned. I don't think that the sims (FSX, P3D, Xplane) support different frequencies in different sectors of the same airport, so I assume that Vox simply reads the frequencies in the order they are listed in the airport.bgl file, but so far, I didn't manage to find out the logic according to which a frequency is picked. It's neither always the lowest nor the highest one. Does anybody know how Vox prioritises the frequencies? I assume Vox simply takes the first frequency that it listed in the bgl. but how can I see the order of frequencies in the airport.bgl file?  Is there an external program (ADE,AFX) that shows the frequencies in the right order such that for example the prioritised frequency always shows on top in the frequency list?

Best regards

draci

[vadriver 247]

draci

perhaps a way to view / print an airport's comms/atis is to review the updated makerunways compiled runways.txt file.

there is also the "comms".log files in vox's appdata to see  / compare with the above.

be interesting to hear your conclusions .... my pnf does what's assigned.

Edited November 22, 2019 by vadriver

[bmaik 11]

Thank you vadriver once again for the hint, I'm going to check this out on my next few flights and report back.

 

[bmaik 11]

Thank you vadriver for the excellent hint, strange that I've never tried this before, I'm going to check this out on my next few flights and report back.

 

Edited November 23, 2019 by bmaik

[bmaik 11]

I can confirm thatt VADriver was right: For the last 5 flights Vox always used the first frequency in the runways.txt file if an airport had multiple frequencies for the same station, so this can be considered solved. Thx vadriver, once again.

 

[jabloomf1230 2,445]

14 hours ago, bmaik said:

I can confirm thatt VADriver was right: For the last 5 flights Vox always used the first frequency in the runways.txt file if an airport had multiple frequencies for the same station, so this can be considered solved. Thx vadriver, once again.

 

I don't believe that any 3rd party ATC add-ons do anything different than that. The reason for multiple frequencies being assigned to an airport for a given ATC function has to do with sectoring, either on the ground or in the air. Unfortunately, for example, there is no information contained in the BGL file format to allow for an ATC add-on to figure out which frequency goes with which approach sector. Approaches, departures and arrivals are all directional. Additionally, certain frequencies are assigned to specific aircraft types. So if there was some logic in the airport's frequency order in the BGL file, there might be a possibility of utilizing multiple frequencies. Maybe MSFS 2020 will add that kind of realism.

[Mad_Mac 21]

What I have noticed with regard to Class C airspace (I don’t usually fly into Class B) is VoxATC almost always uses the opposite of the frequency it should. On a flight chart there will be a white box surrounded by a magenta border with the approach frequency in the box. The box closest to your direction of approach should be the frequency used. VoxATC almost always uses the frequency in the box on the opposite side of the airspace from my approach. Curious if anyone else has noticed this. 

Edited December 30, 2019 by Mad_Mac

[jabloomf1230 2,445]

It's probably just a coincidence as to how the frequencies are arranged in the BGL file. To my knowledge, there is no mechanism for storing directional (frequency by sector) information in a BGL file, so VOXATC would have to be very clever to simulate that behavior.

[Mad_Mac 21]

1 hour ago, jabloomf1230 said:

It's probably just a coincidence as to how the frequencies are arranged in the BGL file.

Maybe I only notice it when it is not correct (selective attention). 

[jabloomf1230 2,445]

While stumbling around the internet, I discovered this very old post by the late flightsim legend Jim Vile, that  explains the issue discussed in this thread. It's from 2010 and applies to FSX, but the same logic still holds for P3d4:

https://www.fsdeveloper.com/forum/threads/runway-specific-tower-frequencies.22501/

Jeppesen does keep track of which frequencies correspond to which operational condition, but I don't believe that Navigraph provides that information for any of its formats, since the sim can't use it. You can however see the information if you look at the RXP GTN 750 database with the gauge.