FRAME NOT FOR ME in ALE Comms

[n5pwp]

I just started monitoring ALE on HF. The COTHEN frequencies seem to give the most activity (Haven't found a single Ham ALE transmission). I use both PC-ALE and MARS-ALE and monitor using an RTL-SDR. So I receive only. I've noticed several times a conversation like this:

[01/09/2017][05:22:59][FRQ 05732000][MONITOR: MONITOR CALL HEARD - DEFAULT - FORCED RESUME SCAN - Tell N2CKH/NNN0WWL]
[01/09/2017][05:56:40][FRQ 05732000][MONITOR: MONITOR IDLE - FRAME NOT FOR ME 10000]
[01/09/2017][05:56:40][FRQ 05732000][MONITOR: MONITOR CALL HEARD - FRAME NOT FOR ME 15000]

I have a few questions about this exchange.
1. Why do I only see this in the MARS-ALE receive window and not in the PC-ALE window? Does the program filter it out since it is not Amateur Radio transmissions? It allows the SND transmissions.

2. Did the receiver of the message actually get a message meant for someone else and it kicked it back out?

3. Is there a document that explains what typical exchanges would be? Or what these MONITOR: messages are?

4. Why does one end with 10000 and the other with 15000?

To answer those that reply with "Google is your friend". I have already done that. I have spent the last several days crawling all over ALE in Google. I have found several good resources for decoding the addresses.

Anyway, I'm hoping to see something more interesting than the SND frames and the "Frame not for me" messages.

Oh yeah, one more question. I'm using a virtual audio cable so I can run several pieces of software to decode other digital signals on the same frequencies. Is there a way when a voice call comes I can pass the audio through to listen to the voice or do I have to use the Stereo mixer in Windows and listen to all the ALE digital signals and wait for a voice signal to come through?

It occurs to me that maybe this is the way ALE works. They find a good frequency and then when they connect then they go to voice? I thought there would be some traffic passed as text. Is that not how ALE is supposed to work?

Enough questions for now. I look forward to chatting with others that have more experience with the mode.

Thanks.
Mike

 

[k8krh]

I am not into ALE myself but the frequencies ..look up HFALE or PCALE they have a list of frequencies. One can hear it on 30 meters during the day but I have never seen one message on the screen.
DOCTOR795

 

[n5pwp]

Yeah, I have already gone to the HFLink site as well as the PCALE site and have monitored the digital amateur radio frequencies and my experience has been like yours. Nothing. There is more activity on the COTHEN frequencies. OK, thanks. I will try to do more searching around. There are lots of organizations that use ALE.

Mike

 

[K5MPH]

They look like status link messages letting the two radios know that the other is still on the air....

 

[n5pwp]

After seeing this more I'm beginning to think since there is no address info in the message that it may be generated by my copy of MARS-ALE. I think it is saying the frame that was sent is actually "not for me". It is not addressed to me. I have seen no messages in the clear so I suspect the programs are written to protect the message content from people that are not intended to see them. So what we're left with is a bunch of sounding messages. Mildly interesting bu not something that will hold my attention. I have since moved on to STANAG decoding and most of that is encrypted. Maybe I'll try decoding numbers stations. ;-)

They kinda take all the fun out of monitoring this stuff. Oh well ...

 

[ka3jjz]

Actually a far better place to go is to identify frequencies (and other digital targets) is the UDXF mailing list which recently moved to groups.io . They have a great many folks that watch for ALE comms - it's so big now that it's practically it's own little sub-group, much like the numbers folks.

I also have a link to Hugh Stegman's ALE frequency list, which is very comprehensive, but is constantly growing, so it's never really complete. Still you get a real good idea of the number of organizations that use ALE besides the amateur community...

http://www.ominous-valve.com/ale-list.txt

Mike

 

[902]

They kinda take all the fun out of monitoring this stuff. Oh well ...

Oh? Why don't you look into being one of the Armed Forces MARS stations? It's challenging, you'll learn a lot, and you may be on the other end of what you're listening to.

 

[n5pwp]

ka3jjz: I have explored those sites and documents already. I have had some luck with the USAF ALE stuff and pretty bad results with the MARS ALE stuff. I think I've seen 1 frame from a Canadian station show up in PC-ALE. The only thing that seems to have regular traffic is COTHEN. Recently there seems to be an uptick in activity there. I don't know what's going on but it seems to be pretty busy these days. I even recorded a bit of voice during one of the ALE transactions. I'm using an SDR to monitor this stuff so there is no capability for scanning using CAT. There doesn't appear to be an CAT drivers for the RTL-SDRs so I monitor a single frequency at a time. But since I now see that ALE doesn't reveal the contents of their messages there's not much incentive to pursue it.

902: As I said above, I'm using an SDR to monitor the digital stuff on HF so no transmit capabilities. Also, I'm a Tech licensee so I only have CW privileges in HF other than in 10M. Of course 10M is dead now. Maybe when the solar cycle comes back up and activates 10 I might try to get in on MARS.

Mike