UHF EAM Simulcast

[Gunslinger36]

Copying "New Villa" at 17:41Z 12-03-14 simulcasting 30 character EAM with 6 character authentication on 311.0 and 323.8 MHz in Central Missouri. Probable E-6 activity. Will be checking ADS-B.

 

[SCPD]

looks like they were on orbit around the St Louis area.
http://planefinder.net/flight/GOTO FMS

 

[Gunslinger36]

I activated my ADS-B configured SDR dongle but did not see it. I am located in West Central, MO. My antenna for ADS-B is not the best (indoors, sitting on the window sill towards the West) and I have a hard time seeing anything in the Eastern half of Missouri. Thanks for the info. I'll try using Planefinder next time.

 

[ColoradoRedlands]

Copying "New Villa" at 17:41Z 12-03-14 simulcasting 30 character EAM with 6 character authentication on 311.0 and 323.8 MHz in Central Missouri. Probable E-6 activity. Will be checking ADS-B.

I am curious, what makes 6 of the chararcters the "authentication"?

 

[SCPD]

I believe the authentication code is announced at the end of the EAM message. Not sure if the number of characters matters. Once authentication is verified by the receiver the message is then passed on. Here's a video that shows how the process works during a E-6 TACAMO mission.

https://www.youtube.com/watch?v=5tWjX-xiVVI

 

[ColoradoRedlands]

I believe the authentication code is announced at the end of the EAM message. Not sure if the number of characters matters. Once authentication is verified by the receiver the message is then passed on. Here's a video that shows how the process works during a E-6 TACAMO mission.

https://www.youtube.com/watch?v=5tWjX-xiVVI

Thanks,

I have seen that video before. I think they have to have the whole message decoded before than can delcare it "valid". I thought maybe you had some insight about certain characters, or amounts of characters being the authentication.

 

[K4PIH]

The authentication codes used to come from one time pads. Not sure if they use them anymore.