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Author Topic: 6.739 USB numbers and letters ? "semi-pro" ?  (Read 1452 times)

Offline EliteData

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6.739 USB numbers and letters ? "semi-pro" ?
« on: February 26, 2016, 2302 UTC »
6.739 USB
sound sample included > http://www56.zippyshare.com/v/RVJgbla2/file.html
reading numbers and letters and then says "this is semi-pro out"

Offline ChrisSmolinski

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Re: 6.739 USB numbers and letters ? "semi-pro" ?
« Reply #1 on: February 26, 2016, 2323 UTC »
Sounds like a US Military EAM.
Chris Smolinski
Westminster, MD
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Offline EliteData

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Re: 6.739 USB numbers and letters ? "semi-pro" ?
« Reply #2 on: February 26, 2016, 2325 UTC »
Sounds like a US Military EAM.
very possible since its in the aeronautical band
here is some more interesting information regarding this topic with the attached file below (EAMs.pdf) for anyone else who comes across this topic and is curious.
« Last Edit: February 27, 2016, 0041 UTC by EliteData »

Offline Token

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Re: 6.739 USB numbers and letters ? "semi-pro" ?
« Reply #3 on: February 27, 2016, 0138 UTC »
I moved this to Utility.

This is an EAM sent on the US military (USAF operated but used by all services) HF-GCS (High Frequency Global Communications System).  6739 kHz is one of their regular frequencies and you should hear these messages several times a day.  By the way, although hobbyist are in the habit of calling all such coded messages "EAMs" they are not all EAMs.  But, by design, you can't tell the EAMs from other types of messages, such as FDMs.

Frequencies used are 4724, 6712, 6739, 8992, 11175, 13200, and 15016 kHz.

"SEMI PRO" is a rotating callsign.  In the past this network has variously used rotating calls, fixed calls of the base that originated the message, and MAINSAIL group callsign.  Last year they shifted pretty much exclusively to the rotating calls, and have been using them for many months now.

T!
« Last Edit: February 27, 2016, 0144 UTC by Token »
T!
Mojave Desert, California USA