Mystery Signal found on Mil Air band 364.499.650 cw mode

[stlouisx50]

Mystery Signal found on Mil Air band 364.499.650 cw mode

 

[737mech]

Is this continuous all day everyday? Sounds like a data thing maybe a satellite downlink? Have you tried running a INMARSAT decoder on a recording of it?

 

[vagrant]

364.5 / 3 = 121.5 MHz

It may be an ELT, but they typically sound different. I am not an ELT expert though. Hmm...I wonder if it may be a PLB. Do those devices also use 121.5 as well as the 406? The warbling tone and third harmonic has be fixed on a distress beacon versus some digital data.

@stlouisx50 - Do you live near an airport? Can you still hear the signal?

 

[gary123]

I doubt its a ELT as well. ELT are usually 243.000. I also agree it does not sound like a ELT burst. It has all the hallmarks of a telemetry marker/beacon. The data appears to be the same packet.

One consideration is this may be a foreign market device being used illegally in NA.

 

[stlouisx50]

I have never used that software. I only have the ability to use Windows based software unfortunately with my Rtl-SDR.

The nearest airport is a very small one, 6 miles west of me.

Then Fort Lenardwood is about 40 miles north of me.

 

[gary123]

If you have a laptop you could do a bit of DF detective work. The signal looks nice and clean. Even testing 5 miles away will give you an idea of how powerful it is. The larger the coverage are the more possible others can pick it up and ID it.

 

[vavolff]

This has some Link 11 traits, but I very highly doubt that one!

 

[stlouisx50]

If you have a laptop you could do a bit of DF detective work. The signal looks nice and clean. Even testing 5 miles away will give you an idea of how powerful it is. The larger the coverage are the more possible others can pick it up and ID it.

I will key in the frequency in again and see if it's still there. Being it was a touch more than a weak signal. If I hear it, I'll make some time to drive each direction and see which way it is and head that way 😀👌