Some frequencies can´t be activated with F1 GTN Complete

[matthiasmjf]

Hi,

excuse me for copy-and-pasting, The same thread I posted on the Flight1 forums because I don´t know if the issue lies with the GTN radio unit or FSAD´s radio frequencies:

"Hi,

I have an issue with frequency switching. Sometimes P3D ATC wants me to switch frequencies but the Flight1 GTN doesn´t allow that exact frequency to be dialed in. For example (but I had this happen in other cases in Switzerland but also around Prague) Lausanne Approach is on 118.830 but the GTN does not switch to this frequency and instead just activates the closest one: 118.825. I thought it to be an 24 / 8.33 khz channel spacing issue and switched between the two in sim in the GTN setup page but to no avail (there it says 118.82). Same behaviour when trying to type it in manually in the unit, rather than letting the ATC dialogue set the frequency

Any ideas? BTW, I am using the FSAerodata airspace and frequency updates which are based upon the Navigraph AIRAC data, Flight1 GTN Complete (GTN 650 and 750) and P3D 5.1 HF1.

I wonder how to fix this and where the issue lies: P3D5.1 HF1, FSAerodata/ Navigraph, the GTN, the trainer software?
Any ideas or by any chance someone who has a similar problem?

BTW, the default radios do work..."

Best,

Mace

BTW: The ICAO paper on the distribution says 118.830 is not used around the world, maybe that is considered in the Garmin database and thus activation is blocked? But why is it in the Navigraph data then and, as it happens, in the info for Lausanne APP on the web?
https://www.google.de/url?sa=t&rct=j&q= ... e2NydSH7RY

[matthiasmjf]

...then again the official airport homepage lists 118.830 as the APCH INFO frequency...
http://www.lausanne-airport.ch/pilotes/frequences.html

I mean the easiest fix for now is to fly NORDO in those places where I can´t tune in the frequencies and wait with ATC contact untill I get into the next sector but it bugs me and is particularly annoying when I should get approach vectors by ATC.

[fsaerodata]

Hi,
I think the F1 GTN family is not compatible with 8.33khz spacing on P3D v5. The GPS trainer is compatible, but the link between the GPS and the simulator still rounds to the nearest 25khz and 3 digits, which seems strange since they released recently a vers. compatible with P3D5.

On the other hand, FSAerodata works correctly with default airplanes and selecting the freq. through the ATC panel window.
Remember to set the option "8.33kHz spacing" on FSAerodata config tool, or untick the option to use 25kHz instead. The latter one should solve the problem until Flight1 fix the incompatibility.

Regards,

[matthiasmjf]

Thanks Jose,

indeed the issue seems to lie with the GTN. However, I think it may be the interface, as you stated but I find it strange that even when I manually dial in the frequency in the unit it does not accept 118.830 but rather goes to 118.825 (8,33khz) or 118.82 (25khz).
I check next whether this also happens when starting the standalone trainer and then actually turns out to be a Garmin issue...
Thanks for your help!

Best

Mace

[matthiasmjf]

Hi Jose,

seems indeed a Flight1 issue, as you said. In the Garmin Trainer without flight sim started and with spacing set to 8.33 118.830 can be set. Will have to see what F1 support can do about it.

Thanks

Mace

[matthiasmjf]

Hello Jose,

Flight1 has indeed confirmed that 8.33 khz is not supported and it is unlikely it ever will be as the GTN Complete apparently isn´t exactly a bestseller.
Need to ask whether RealityXPs Unit, which is also based on the Garmin Trainer, supports 8.33...
Meanwhile... what happens when I disable 8.33 khz in your programme? I rather have the whole world in 25khz or some non-real world frequencies than those ATC black spots...

Best

Mace

[fsaerodata]

The RXP unit supports 8.33kHz.

Acc. the FSAerodata User's Manual:
8.33kHz spacing: when selected, the database includes airport comms with the new separation of 8.33kHz between channels. When deselected, they are rounded to 25kHz spacing. This option is available only on Prepar3D v5 and higher.

[matthiasmjf]

Thanks a lot!
Maybe I should swap over to RXP...
...and while pondering this decision I´ll switch the config tool to 25 khz. Great to have that option.

Best regards

Mace

[fsaerodata]

Latest news from Flight1:
The Flight1 GTN series has been updated (vers 2.22) to add support for 8.33 kHz com channel spacing in P3Dv5.

Regards,

[matthiasmjf]

Yup, just installed it and it works as it should!
Thanks for your advice!

Best

Mace