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Author Topic: Strange Signal on 14435 kHz  (Read 4989 times)

Offline Strange Beacons

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Strange Signal on 14435 kHz
« on: June 12, 2013, 1902 UTC »
Found this signal while scanning around on the 20 meter band, listening to ham radio talkers.

I'm thinking this may be RTTY or some other sort of data stream from a radio modem.  

Anyone else have any ideas as to what this might be?

http://youtu.be/EWWBnmaOZpQ

Update: One person commented on this video at my YouTube channel, identifying the signal as a satellite transmission.  Anyone else agree?
« Last Edit: June 13, 2013, 0220 UTC by pcldltr »

Offline Token

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Re: Strange Signal on 14435 kHz
« Reply #1 on: June 13, 2013, 0040 UTC »
No, it is absolutely not a satellite transmission.  In the first place satellites do not, in general, use HF, and when they do it is generally a higher frequency (above 20 MHz in general).  And in the second place I know what it is, as would many on this board, lets just see if I can get the answer typed first. ;-)

This is a 850 Hz shift FSK signal, 50 or 75 bd (not running software to measure it right now).  It is a form of RTTY.  This is almost certainly encrypted (most of the 850 Hz stuff is).  It is sometimes referred to as STANAG 4481.

This is very possibly US Navy NPM, Lualualei, Hawaii, as they are known to use a frequency very close to this, and your example is slightly mistuned.

T!
T!
Mojave Desert, California USA

Offline Strange Beacons

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Re: Strange Signal on 14435 kHz
« Reply #2 on: June 13, 2013, 0224 UTC »
Thanks, T!, that is what I initially thought the signal was, i.e., some sort of RTTY, as I have heard something very similar to this before (and it turned out to be a RTTY signal).

I am in Seattle, WA USA and when I tune around on the ham bands from here, I often can pick up a lot of voice traffic from Hawaii.

Cheers.

No, it is absolutely not a satellite transmission.  In the first place satellites do not, in general, use HF, and when they do it is generally a higher frequency (above 20 MHz in general).  And in the second place I know what it is, as would many on this board, lets just see if I can get the answer typed first. ;-)

This is a 850 Hz shift FSK signal, 50 or 75 bd (not running software to measure it right now).  It is a form of RTTY.  This is almost certainly encrypted (most of the 850 Hz stuff is).  It is sometimes referred to as STANAG 4481.

This is very possibly US Navy NPM, Lualualei, Hawaii, as they are known to use a frequency very close to this, and your example is slightly mistuned.

T!


 

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