Problems with frequency wheel

[mase]

Hi!
In all aircraft I tested, some frequencies used for fgcom cannot
be set in the cockpit. They can only be reached, when entering
them directly in the radio dialog.
An example is EDDF_TWR. The fgcom frequency is 127,320.
In the aircraft the frequency is 127,325. I did not hear anything,
when that frequency was set. fgcom should deal with that.

[jomo]

Sorry - I am not sure what you mean:

In all aircraft I tested, some frequencies used for fgcom cannot be set in the cockpit.

That is true: There are frequencies available, that have not been picked up in the FGCOM program (but 127.32 is available!). If you have problems with a frequency you can check the "positions.txt"-file inside your FGCOM-directory. Search e.g. for EDDF and you find the 5 available frequencies like:

Code: Select all

EDDF,121.800,50.027738,8.561658,GND,Frankfurt am Main
EDDF,127.320,50.027738,8.561658,TWR,Frankfurt am Main
EDDF,121.900,50.027738,8.561658,DELIVERY,Frankfurt am Main
EDDF,136.120,50.027738,8.561658,LANGEN RADAR,Frankfurt am Main
EDDF,118.720,50.027738,8.561658,ATIS,Frankfurt am Main

Also some FGFS-GUIs do not support the 3rd digit after the decimal-sign - but for 127.320 that is no problem (a none digit given = 0)

They can only be reached, when entering them directly in the radio dialog.
An example is EDDF_TWR. The fgcom frequency is 127,320.

Yes - that frequency 127.32(0) is used at EDDF --> myself and all my visitors (with FGCOM) have no problems with that since years!. (Watch that you do not use a "," when defining the frequency! The above commas are not decimals but "value separators"!)

In the aircraft the frequency is 127,325. I did not hear anything, when that frequency was set. fgcom should deal with that.

It is correct that some aircraft etc. cannot deal with that 3rd digit ("5") after the decimal-sign --- but why would you want to use that??
Why do you want to use the 127.325 for EDDF(twr)?? I know it is listed in some Internet-docs - but nowhere in the FGFS documentation! e.g.:

see FGFS -> menu -> Equipment -> Radio Settings -> ATC Services in range (when you are at EDDF!)
When you arrive at EDDF ATC tells you to use 127.320
see http://www.emmerich-j.de/EDDF/EDDF-Layout.png
etc.

[F-JJTH]

An example is EDDF_TWR. The fgcom frequency is 127,320.
In the aircraft the frequency is 127,325. I did not hear anything,
when that frequency was set. fgcom should deal with that.

Why do you want to use the 127.325 for EDDF(twr)?? I know it is listed in some Internet-docs - but nowhere in the FGFS documentation!

@jomo: I think mase want to point us to the realistic side of radio communication, in real life, 127.320 doesn't exist for EDDF, 127.325 is the correct (used in real life) frequency.

@mase: FGCom is not the cause of this problem here, the problem come from Asterisk server, and even the script which generate the DialPlan used by Asterisk. I've fixed this here on my local Asterisk server. I plan to setup a new Asterisk server with this feature with a domain like fgcom.flightgear.org (need to deal this with Curt )
All of this will be available for FG 3.0 (at least I hope )

Cheers,
Clément

[jomo]

I think mase want to point us to the realistic side of radio communication, in real life, 127.320 doesn't exist for EDDF, 127.325 is the correct (used in real life) frequency.

To my knowledge that "...5" (e.g. 127.325) frequencies are relatively new in the Real-World and I am very glade to hear that somebody is attacking that technical problem. Especially because I know that that will be a rather big problem inside FGFS - for which I have NO proposal of how to handle that inside FGFS! But I guess you are aware that we do not just need to change the FGCOM-Servers - but also have to take care of all the models with old style Radios!!
e.g. the well known and much used c172p has 2 BendixKing KX165TO Radios installed (also in real life!) that cannot handle those 6digit numbers! (at least you cannot set them with the manual dials!)

I do not yet know how to deal with that for the multiplayer environment - when old and new models should be able to communicate! Probably we then have to use/allow only the short numbers. That is why I strengthened the point the users for now (and may be for ever) should look which frequencies are used and/or advised by ATC at a given location. I guess real big airports ( like e.g. EDDF) do not care much about a c172p being able to communicate with a 747-8 or A380 -- we in FGFS should keep that possibility!

I am looking forward to 3.0 - hopefully we then also have the integrated FGCOM.
Thanks for your hint.
Cheers,

[F-JJTH]

This "5" is here since long long time But he is not displayed by most of radio stack. Since 1972 radio frequencies are in 25KHz spacing.
When you tell to someone to set "118.17", in reality the frequency is "118.175". In France when you talk with ATC, the controller will tell you "118.175" not "118.17". Maybe in other country you say only "118.17" I don't know since I only fly in France.

You can be sure that KX165TO is a 25KHz spacing and use 127.325 instead of 127.320
In fact all of this begin to be old since we already started a 8.33KHz spacing ! All europe will be on 8.33Khz at 2018. Every liners (in real life) have a 8.33Khz radio now since 8.33Khz spacing is already active above FL195.
But for now we can't use 8.33KHz spacing because apt.dat (even recent one) are not ready for this.

Cheers,
Clément

[jomo]

This "5" is here since long long time But he is not displayed by most of radio stack. Since 1972 radio frequencies are in 25KHz spacing.

Well - sorry for my age - my pilot license is from 04-09-72!

But seriously: What is your answer to the original question from "mase" - as of today?
I still suggest: Ask the ATC and/or see the now FGFS documentation (not the Internet!)

And thanks for you support for FGCOM - I love it

[F-JJTH]

Your age is perfect !
Sure, as of today you need to adopt a convention where the ATC tells to pilot the frequency.

I'm glad to see that my effort is welcome thanks you

Cheers,
Clément

[vector]

Correct me if I'm wrong, but a client transmits it's first (COM1) frequency value over MP protocol, so this could be used by pilots to know the frequency (the first one) an ATC is tuned to. Recent versions of OpenRadar display this frequency when they see each other. Maybe fg could display it too in the pilots' list (as it also shows the squawk code).

Vector

[jomo]

Correct me if I'm wrong, but a client transmits it's first (COM1) frequency value over MP protocol, so this could be used by pilots to know the frequency (the first one) an ATC is tuned to. Recent versions of OpenRadar display this frequency when they see each other. May be fg could display it too in the pilots' list (as it also shows the squawk code). Vector

Well I guess you talk not about the basic FGFS-usage - but upcoming tools related to OpenRadar in conjunction with FlightPlans, SquakeCodes, etc.. But even there all FGCOM-transmissions follow the same rule:

Today (and tomorrow...) the ATC has to set the frequency he wants to use like any other FGFS-pilot (-e.g. he can select it with the COM1 (2,3,4) selection list, or define it when starting FGCOM)
- that frequ is not distributed by the MPservers -- the MPservers are only used to check the range that the sender is in (same as with the Flight-models)
- in the "long range" future the frequencies may be inserted into the flightplans that are distributed via other servers - but I doubt that that will be very useful in regards to the "FGCOM frequency to be used" - because every ATC may select another frequency (or even procedure, e.g. Radar, Approach, Tower, GND, etc..) - in addition nobody knows in advance which ATC (if any) will on duty when the pilot arrives!

I guess your suggestion is a nice dream - but difficult to do, considering the very mixed environment between pilots, ATC's, FGCOM, FGFS, knowledge of users, etc..
Even in the real world that cannot be done - the pilot is supposed to know the standard frequencies en-route in advance - but uses them only after advised by ATC!

[mase]

I only wanted to say, that you are not able to tune to that frequencies with
the radio knobs in the pit. With the radio dialog it is no problem. I like to
use the cockpit controls instead of the dialogs to be more realistic.
I also like autopilot implementations, that can be fully controlled in the pit.

[Secret_Hamster]

Yes I have noted this issue as well.

In essence the problem is the dialplan.

If we are agreeing that the frequency step is 25khz then 124.22 on the radio stack should indicate 124.225 transmit/receive, which I believe it does. Therefore in essence the dialplan is wrong when it specifies 124.220 as the actual freqency for that channel. I'm not sure if FGCOM3.0 will amend this, it would be nice if it did.

What is going to happen with the 8.33khz separations? I presume we will need to produce some updated radio stacks.

[F-JJTH]

Hi,

fgcom.flightgear.org has already been patched to solve this 25KHz problem. So you can connect 124.225 or 124.220: you will be connected to the same frequency (the correct one 124.225)

FGCom 3.0 is already ready for that too and 8.33KHz spacing has been implemented and is also already working

In fact FGCom 3.0 will come with a lot of big change and improvement and new feature, but for now there still some work. I plan to create a new thread to inform people about the progress.

Regards,
Clément