Does Anyone Know What This 30 Meter Signal is?

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  • Updated 4 years ago
This signal stretches all the way from 10.125 to 10.145 MHz.  Does anyone know what it is?  It was really messing up 30 meters this evening.  (23:30 UTC)
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Ken - NM9P, Elmer

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Posted 4 years ago

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Photo of Rick Hadley - W0FG

Rick Hadley - W0FG

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No, but I heard it on another band too....seems to me it was 15 but might have been 17.  I thought the radio had gone south for a moment or two....
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George Molnar, KF2T, Elmer

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Didn't see it here, so either propagation was favoring you, or it's relatively local, Ken. Looks like a digital signal of some kind.

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Norm S

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I've seen the same signal up on 10.205 as well.   I have no idea what it is though.  If you listen to it on AM it sounds like an airplane!

Norm - KL7RS
(Edited)
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Ernest - W4EG

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Similar signals have been seeing in San Diego. 

The FCC San Diego office has been notified and  are following the trail.   We have been seeing them for the passed 5 or 6 months.  If my memory serve  me correctly, N6LR is the individual that is working with the FCC but don't hold me on that call. 

The FCC ask us for bearings by pointing our beams for maximum S meter reading. They triangulated the position to be north of San Diego. However, we have being seeing it on the edge of 6..9 - 7.0MHz with what we are calling the widest part and to the right, what appears to be some type of modulation penetrating all the way up to 7.050MHz or higher.

Check with your local FCC office and mentioned the above example. They properly will contact the San Diego office.

By the way, this is NOT a Flex problem.  We had a lot of help with the rice box users: Since they also were being affected. 

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W5UN_Dave

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I've seen this on other bands also. It looks like some sort of RADAR signal
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Ernest - W4EG

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This is a follow up to my previous note.

I received the following letter from Larry N6NC (see I came close to the correct c/s! I only missed it by two letters.)

"We got to the point of triangulating the signal as skywave (long distance, not local) from the north direction from La Jolla, FCC field guy referred the matter to their national fixed triangulation station, and the FCC boss for San Diego cancelled the request saying we should contact the FCC's interference lady in Washington - basically blowing us off."

Hope this answers the question and how far you are going to go!

 "Government at its best" 

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Ken - NM9P, Elmer

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It sounds to me like the FCC already knows what it is and doesn't want to implicate some other government agency for out of band operation?  I know that 30 Meters is a "shared" band, but taking up 20 out of 50 Khz is taking more than your fair share!
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Al / NN4ZZ

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May or may not be related, and the attributed cause may or may not be correct but FWIW --- Near the end of a QSO  with a ham in the Netherlands this week we had strong QRM with a similar pattern on 17M CW.  It was moving/drifting slowly across the band.   In a follow up email he said it was Russian radar.   

Regards, Al / NN4ZZ  
al (at) nn4zz (dot) com



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Robbie - KI4TTZ

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DRM, perhaps?  The JT65 freq on 40 meters gets clobbered at my house a lot by one of those signals.  Never knew what it was until I got my 6000 and was able to "see" the signal on the panadapter.  

http://en.wikipedia.org/wiki/Digital_Radio_Mondiale

Found a photo online of what it looks like:  http://www.radiohobbyist.org/blog/?p=890

-Robbie




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Ken - NM9P, Elmer

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I thought about DRM at first, but it is twice as wide (20KHz) as the 10 Khz DRM signal.  My guess is that it is some sort of highly multiplexed data signal, or OTH Radar, or a jamming signal from someone who doesn't like all the W1AW/p operations in the band! (not really).  (BTW, I am up to about 273 contact points, but only 222 confirmed so far!)
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Ernest - W4EG

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The FCC never (to my knowledge) ID the signals or said anything about the software.  So DRM and anything else is just pure speculations.

The FCC were made aware of the interference and they worked for months.  As I said before, they asked us to let them know and to take pictures. They even visited N6NC to check on the problem.

They are aware of it; however, their mouths are shut!  

(Edited)
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Michael - N5TGL

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Without hearing it, I'd have to say OTH radar.

http://en.wikipedia.org/wiki/Over-the-horizon_radar