ACARS software

[Quaxo]

Hello,
I just started experimenting with ACARS decoding, and I have a question (well actually I have tens, but I'll just ask one! )
I use my UBC3500XLT to receive the frequency, connected to my PC with an audio cable. I tried all the software I could find to do the decoding job. By reading all the posts about ACARS here, I was under the impression that acarsd is the best software... But I downloaded the Airnav ACARS Decoder demo, and by running side-by-side Acarsd, Wacars, and the Airnav program, I have to say that Acarsd and Wacars miss about 90% of the messages that are actually decoded and shown by Airnav ACARS Decoder. I wonder what might be happening? I like the Acarsd interface better (and the fact that it's free) but it's no use using it - I just ran a 6 hours session, and while Airnav Decoder received about 250 messages, Acarsd decoded only 18. Any idea why this is happening? I can actually hear the packets, most of them are quite clear, but Acarsd just ignores them...

Thanks
Cristian

 

[trainman111]

I have the same problem. I haven't figured out if there is a setting that is wrong or what. I hope somebody can "enlighten" us as to what needs to be fixed.

 

[kd5dga]

Watch ACARSD screen.on the bottom right corner should show the volume into for the program.Make sure that this is above 15 to about 25 without any acars transmissions present.Either use you radios volume or use the volume control in windows.
BTW are you using your line in or microphone? Use the line-in as the input.Make sure that line-in is selected under the volume options for recording in windows.I dont use the microphone input so I disable this under the same window, infact my line-in is the only selected no other inputs.This keeps confusion down.

 

[trainman111]

The volume is at the right setting, but I use the mic jack because for some reason, ACARSD doesn't recognize the line-in jack for some reason. I've got the jack turned on but it just doesn't want to recognize it.

 

[kd5dga]

Line in is better,I dont know why but most folks use the line-in for any decoder.Check to see if you mike boost is on.Turn the boost off.This maybe over driving the soundcard.

 

[trainman111]

Nope, it's off. I just can't figure out why ACARSD won't recognize the line-in.

 

[kd5dga]

will any other program that needs a soundcars recognise the line-in selection?
I will see if I can find the options that will make this work.

 

[trainman111]

Yes. My recording software recognizes it just fine.

 

[Bill_White]

Back when I was running my server, I remember the volume control was VERY touchy.
If you subscribe to the ACARSD yahoo group, check the archives back on
9/21/2004 thread "Volume Settings" again on
12/18/2004 thread "Volume Control Settings" and
2/4/2005 thread "Sound Settings"
If you don't want to subscribe to "another" group, to sum it up....
Go here and grab the free meters (DXVUMeterNET):
http://software.xfx.net/netcl/dxvunet/index.htm
Set the the volume, with squelch open, so three or four bars light up and adjust your line in as needed...
If I remember right....My best results were with the line in recording volume about 1/4 on and three bars on constant with the fourth bar flickering. This should give you a good starting point..

 

[chgomonitor]

ACARS notes

I haven't seen anything which works as well as the AirNav ACARS decoder. But check the settings in each of the programs in question to insure you have similar message filtering settings. All should pour in data in literal (unfiltered) modes. Keep in mind, ACARS employs a form of error correction so you'll often see the same message repeated many times - with varying degrees of errors.

Might try a different radio, too. My experience is that different software packages perform differently with different radios. Probably an effect of the filtering of the signal from the radio.

In general, just sit on a single active link frequency with the squelch open. You want to use the lowest possible audio / volume level you can and still copy packets.

Experiment with line level outputs, earphone and speaker jacks off the radio as feeds. You'll probably find one works better than the others.

Multimode for Mac users does a fairly job with ACARS, too.

 

[kd5dga]

Here are a few questions;
1. how did you set up the program?
2. Did you use the quick install?
3. What sample rate are you using for the soundcard?

The reason this can be very inportant on the set up. Got into the ACARSD folder double click on the file that says "setup" now this will allow you to properly set the program up.Look under the sound configuration under the setup what is checked? Now this may take some time to get it right.I had to experiment with mine.I am sampling at a 44k rate since my computer sound supports it.Try the different options of sample rates to see if you will start get decodes.When you are making these changes make sure to go to the bottom of the configuration and click on"write a new ACARSD .ini" this will save the changes.
ACARSD is a great Free program but the documentation is poor.I had to spend hours and days to figure the program out.Once you are able to get the program up and running then I will explain about the mapping.It is simple but takes time to get used to.

 

[datainmotion]

I use ACARSD and in a 2-hour session, I'll decode hundreds of messages - all while mobile (Denver Metro area). The only real problem I had was using a stereo patch cable at first. It needs to be a mono patch cable or I had to pull the cable half-way out.

 

[Quaxo]

I have been experimenting quite a lot with the relative performance of Acarsd and Airnav ACARS Decoder. I have seen some occasions where either program decoded some messages that the other didn't (being fed the same audio input); anyway, even in the best condition, Acarsd seems to decode at best 80% of the messages that Airnav Decoder decodes. Here's a table with some of my results: I have indicated the number of passes (in the Acarsd decoder setup), the Acarsd volume when receiving only noise, the number of messages decoded by both programs in a session when being fed the same input, and the final ratio:

no. of passes Acarsd volume Acarsd Airnav Decoder Acarsd/Airnav ratio

5 pass. Vol 20 ca 186 236 79%
10 pass. Vol 20 ca 57 86 66%
10 pass. Vol 20 ca 80 115 69%
7 pass. Vol 20 ca 100 185 54%
7 pass. Vol 10 ca 28 111 25%
7 pass. Vol 15 ca 171 241 71%

I'm still trying other settings (I'm currently trying 5 passes, Vol. 15) but it seems that I get best results with 5 passes; still, it only decodes less than 80% of the messages that Airnav can decode. That's too bad, because Acarsd is really a great program, much better than any other for interface and features, IMO.

Cristian

 

[kicktd]

I've used ACARSD with pretty good success (haven't tried the demo of Airnav ACARS Decoder yet) but one reason why it is not seeing the line in is that you have to manually select this in your volume options. To do this:

Double click the speaker icon at the bottom right of your screen near the clock
On the Volume Control panel that pops up click options and then Properties
Under "Adjust volume for" click on recording and click OK
This pops up the Recording Control, click on Select under the "Line In" section and now Line In will be used for recording.

 

[trainman111]

I've tried that too. It still won't recognize it. I'm going to take a look at some of the other suggestions too and see if I can figure it out. This week is a very busy week but I'll try it out once I get some free time.

 

[kicktd]

Hmm that is odd and the only other thing that I know could be wrong is a sound card setting within the program. Hope ya get it working!