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Author Topic: Unknown 40 meter signal group  (Read 195 times)

Offline Teotwaki

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Unknown 40 meter signal group
« on: November 20, 2022, 1505 UTC »
I started out hearing what I thought was some sort of single frequency fast dasher beacon here at home

1.  7900 to 8020 - (kHz)
2.  1450 (UTC)
3.  ongoing
4.  CW
5.  Orange County, CA
6.  Narrow fast pulses

Looking at the KFS Omni I see this thing blanketing the spectrum with parallel signals above and below 8 MHz.

Radar?
Jim
NRD-525, Elecraft KX3 and Elecraft PX3 Spectrum Display
76' end fed long wire & 66' off-center fed dipole for 10/20/40 meters
Orange County, SoCal, The better half

Offline Token

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Re: Unknown 40 meter signal group
« Reply #1 on: November 20, 2022, 1543 UTC »
Looking at that frequency range at 1540 z I see several signals between 7900 and 8030.

There are some fast CODAR between about 7900 and 7980.  On 8000 there is (what is probably) a North Korean pulse jammer, it sounds like one, but if it is, what it is trying to hit on that freq I have no idea.  And between 8000 and 8015 is a Chinese radar.

Without recordings and / or screen shots we may not know what you heard.

T!
« Last Edit: November 20, 2022, 1549 UTC by Token »
T!
Mojave Desert, California USA

Offline Teotwaki

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Re: Unknown 40 meter signal group
« Reply #2 on: November 20, 2022, 1653 UTC »
Looking at that frequency range at 1540 z I see several signals between 7900 and 8030.

There are some fast CODAR between about 7900 and 7980.  On 8000 there is (what is probably) a North Korean pulse jammer, it sounds like one, but if it is, what it is trying to hit on that freq I have no idea.  And between 8000 and 8015 is a Chinese radar.

Without recordings and / or screen shots we may not know what you heard.

T!

It's still on the air  http://69.27.184.58:8073/, have a listen at 7998.5 in CWN .....

along with other shorter term stuff, left side of the screen shot
Jim
NRD-525, Elecraft KX3 and Elecraft PX3 Spectrum Display
76' end fed long wire & 66' off-center fed dipole for 10/20/40 meters
Orange County, SoCal, The better half

Offline Token

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Re: Unknown 40 meter signal group
« Reply #3 on: November 20, 2022, 1744 UTC »

It's still on the air  http://69.27.184.58:8073/, have a listen at 7998.5 in CWN .....

along with other shorter term stuff, left side of the screen shot

The stuff on the left of the screen (the changing pattern of PRI lines) is a sounder, almost certainly the one associated with the JORN out of Australia.  Depending on its cycle it might revisit a frequency as often as every 3 minutes, but more commonly every 10 minutes or less.

The stuff in the center sounds like a North Korean pulsed jammer, but I can't think of a good reason for it to be hitting that frequency at that time.  So I am not sure it is actually an NK jammer, but it sure sounds just like it.

T!
T!
Mojave Desert, California USA

Offline WA4FHY

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Re: Unknown 40 meter signal group
« Reply #4 on: November 27, 2022, 2228 UTC »
Token,
Thanks for your comments about about the sig on the lefthand part of the screen;
I've been hearing those for years at various parts of the spectrum but never knew
what it was. I think I posted something on HFU at one time. They would hardly be
noticed on an analog rcvr. Yep, I/m spoiled by my SDR. Whenever I fire up the good ol'
R70, it seems like I'm listening with "blinders" on. :)
SDR-IQ / IC-R70 / IC-735 / FT-817ND / FT-991A, RSPduo,5 band vertical
Near Music City, TN

 


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