Should be some good EAM's tonight

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Jay911

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I suspect the guy who posted it on another forum may have got it from there, or vice versa. They (the other forum) did mention "some Art Bell kook type stuff" that one guy was listening to.
 

Token

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EAM's or FDM'S ? Both are coded messages, done intentionally. FDM's,are Force Direction Messages, predetermined OP-Plan Exercises. EAM's are specifically reserved and used for "Real Time Action", these coded messaages change constantly, self explanatory, for those who defend our Country.
Many hobbyist have adopted the habit (right or wrong) of calling any letter/figure coded voice traffic on the HF-GCS as “EAM” with the exception of the easily recognized Skykings. This is understandable as telling one kind of message traffic from another, when encrypted using the same techniques and similar structures, can be problematic. And the term “EAM” is well known, thanks to Hollywood, and is easy to apply.

Shoot, in this day of changing names and formats to be “current” we really do not have any idea if these messages still carry the same terms. Open source data is years behind today and today they may call them something else entirely and the format might have changed while externally appearing the same. People who know the actual information are probably not going to be talking, since confirmation of the current format, by a person with first hand access and information, would be at least FOUO, and likely above that.

I just accept the fact that people are going to call all similar traffic on the system an EAM and I don’t really worry about it. I almost never log such traffic myself unless there is something significant or amusing in it. I do hear it quite often, as one of the receivers at the house is almost always on an HF-GCS freq, but it is there to hear the other traffic, not the coded traffic.

T!
 

fourthhorseman

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So Far Away....
In Philadelphia,
on what ive got labeled as
SIGONELLA at 9007USB
ive been receiving what id
describe as high speed
morse code.
been hearing it all day.

No idea what it is,im too
much of a rookie to know
at this point.
 

metal57

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UK
In Philadelphia,
on what ive got labeled as
SIGONELLA at 9007USB
ive been receiving what id
describe as high speed
morse code.
been hearing it all day.

No idea what it is,im too
much of a rookie to know
at this point.
This was radioteletype [RTTY] also referred to as RATT by the mil.
 

BMT

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Anyone else catch the 178 character EAM yesterday from Offutt?

BMT
 

Token

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2,162
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Mojave Desert, California, USA
In Philadelphia,
on what ive got labeled as
SIGONELLA at 9007USB
ive been receiving what id
describe as high speed
morse code.
been hearing it all day.

No idea what it is,im too
much of a rookie to know
at this point.
This was radioteletype [RTTY] also referred to as RATT by the mil.
Metal57 is correct that this looks like an RTTY signal. More specifically it is 75 bd, 850 Hz shift FSK. It appears to be encrypted. It is also known as STANAG 4481 FSK. The 850 Hz shift FSKs I see are almost always encrypted. This signal is on this frequency regularly.

To the OP: This might sound like high speed CW to your ear because you are tuned to 9007 kHz and in USB. The typical SSB receiver has a filter width of something less than 3 kHz, often between 2.4 and 2.8 kHz. The FSK you are hearing is on a center frequency of 9009 kHz (at 1600 UTC, April 11, 2013), meaning the two tones (sometimes called “mark” and “space” tones) are on 9008.575 and 9009.425 kHz. If your receiver has a 2.4 kHz audio pass band or IF bandwidth then the upper frequency tone is just outside your passband when tuned to 9007 kHz, and you might not be hearing it or it might be very attenuated. I have seen this signal on this frequency run 100 Hz higher also, and that would put the upper tone further on edge for your passband.

This signal really is not on 9007 kHz USB, for example if I tuned to 9008 kHz USB I would hear the station just as well, in fact maybe better, depending on filters used. The “tuned” frequency is going to be the center frequency minus (or plus, if you are tuning in LSB) the desired offset to put both tones in the proper portion of the passband. I don’t think I have ever seen a “standard” offset listed for this specific type of signal, however whatever it would be would need to put both tones inside the bandpass of the receiver. Since there are so many unknown variables many people report these kinds of signals by center frequency (“c/f”).

T!
 

KB1UAM

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New Bedford,Ma
According to the The DEFCON Warning System we are currently at defcon level 3!!!!!! The last time we were at 3 was during 9/11/01... May even go to 2!!!!! The last time that occurred was during the cold war. Could this current unrest be classified as a second cold war????
 

SCPD

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Did you see the part about Russia.

BTW had a odd station on 11175 around 00:00z that had a whistle which sounded the same as the whistle from HOTEL WHISKEY during the US Navy COMPUTEX exercice from Jan. Had a Three letter call. very weak at washington D.C.
 
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