Mystery mode


Ken Sejkora
 

Greetings all,

I believe it's been asked before, does anyone have any idea of the short-duration blips as shown in the image below?  They span a 700 kHz range from about 14400 kHz to 15100 kHz, and appear to be spaced on discrete 'channels' anywhere from 6 to 10 kHz apart.  I assume it is some type of frequency-hopping spread spectrum mode.  Over-the-horizon radar?  Some new military/government voice mode?  I don't recall seeing it anywhere else across the  HF spectrum, but I seem to notice it here when I'm listening to 20-meter amateur band of 15 MHz WWV.  Usually observed between 1000 and 1400 UTC, but may occur at other times.

Thanks and 73
Ken -- WBØOCV
East Falmouth, MA  FN41ro


Nicholas Shaxted
 

You will find that type of signal quite regularly across hf up to the MUF.

It is, ahem, a spread spectrum signal and it is not OTHR, nor is it a frequency sweep for ionospheric sounding.

 

I am not sure if any amateur software wrangler has attempted to correlate these “blips”, but there might be someone.

Have you asked on Ary’s UDXF group?

 

Nick – g4ogi

 

From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> On Behalf Of Ken Sejkora via groups.io
Sent: 08 July 2022 12:35
To: main@SDR-Radio.groups.io
Subject: [SDR-Radio] Mystery mode

 

Greetings all,

I believe it's been asked before, does anyone have any idea of the short-duration blips as shown in the image below?  They span a 700 kHz range from about 14400 kHz to 15100 kHz, and appear to be spaced on discrete 'channels' anywhere from 6 to 10 kHz apart.  I assume it is some type of frequency-hopping spread spectrum mode.  Over-the-horizon radar?  Some new military/government voice mode?  I don't recall seeing it anywhere else across the  HF spectrum, but I seem to notice it here when I'm listening to 20-meter amateur band of 15 MHz WWV.  Usually observed between 1000 and 1400 UTC, but may occur at other times.

Thanks and 73
Ken -- WBØOCV
East Falmouth, MA  FN41ro


Siegfried Jackstien
 

looks like VERY wide opera (yes thats also a spread spectrum mode)

dg9bfc sigi

Am 08.07.2022 um 14:14 schrieb Nicholas Shaxted:

You will find that type of signal quite regularly across hf up to the MUF.

It is, ahem, a spread spectrum signal and it is not OTHR, nor is it a frequency sweep for ionospheric sounding.

 

I am not sure if any amateur software wrangler has attempted to correlate these “blips”, but there might be someone.

Have you asked on Ary’s UDXF group?

 

Nick – g4ogi

 

From: main@SDR-Radio.groups.io <main@SDR-Radio.groups.io> On Behalf Of Ken Sejkora via groups.io
Sent: 08 July 2022 12:35
To: main@SDR-Radio.groups.io
Subject: [SDR-Radio] Mystery mode

 

Greetings all,

I believe it's been asked before, does anyone have any idea of the short-duration blips as shown in the image below?  They span a 700 kHz range from about 14400 kHz to 15100 kHz, and appear to be spaced on discrete 'channels' anywhere from 6 to 10 kHz apart.  I assume it is some type of frequency-hopping spread spectrum mode.  Over-the-horizon radar?  Some new military/government voice mode?  I don't recall seeing it anywhere else across the  HF spectrum, but I seem to notice it here when I'm listening to 20-meter amateur band of 15 MHz WWV.  Usually observed between 1000 and 1400 UTC, but may occur at other times.

Thanks and 73
Ken -- WBØOCV
East Falmouth, MA  FN41ro


GARY W RUSSELL
 

It looks like SuperDarn (Super Dual Auroral Radar Network) which is used for scientific research.  It is also found near 11500 and other places in HF radio spectrum.  There is an example on the Sigidwiki:

Radar - Signal Identification Wiki (sigidwiki.com)

Gary


Ken Sejkora
 

Thanks Gary.  I wasn’t referring to the ‘wavy’ signal in the middle of the spectrum from 14750 to 14800 kHz, but rather the “speckling” that occurs throughout the entire spectrum which are very short in duration and occur on multiple discrete frequencies as indicated with the short-duration blips in vertical columns spread 6 to 10 kHz apart.

 

I was aware of the Signal Identification Wiki, and have had it bookmarked for several years now.  Thanks for sharing it with the rest fo the group.

 

Ken -- WBØOCV

 

From: GARY W RUSSELL
Sent: Friday, July 8, 2022 03:14 PM
To: main@SDR-Radio.groups.io
Subject: Re: [SDR-Radio] Mystery mode

 

It looks like SuperDarn (Super Dual Auroral Radar Network) which is used for scientific research.  It is also found near 11500 and other places in HF radio spectrum.  There is an example on the Sigidwiki:

Radar - Signal Identification Wiki (sigidwiki.com)

Gary

 


David L. Wilson
 

I am puzzle by the waterfall display on SIGIDWIKI although the audio file there is SUPERDARN.  I have visited 2 sites here in Virginia.  See attached write-up from my visits.


David L. Wilson
 

I should add that the specks that were being asked about look like interference to me.


Kriss Kliegle KA1GJU
 

I've seen them too from southeast NH. The 'pips' are too random for QRM, I was thinking spread spectrum comms myself.
It's hard to actually listen to them, due to not appearing on the same frequency over short periods of time.

73 Kriss KA1GJU


Ken Sejkora
 

I agree with Kriss.  I’m not sure if ‘random’ is the proper term to use regarding the ‘pips’, but the fact that they are  very short-duration intermittent and jump around between discrete frequencies suggests to me that they are not interference.  My experience with ‘interference’ lines is that they tend to be either constant or perhaps periodic at some repetitive sequence.  Perhaps I’ll try recording the ‘pips’ in CW mode on one given frequency and try to analyze the duration and see if there is any identifiable modulation in the short period.

 

Thanks to everyone that has offered their suggestions.  Have a great weekend. 73

 

Ken -- WBØOCV

 

From: Kriss Kliegle KA1GJU
Sent: Saturday, July 9, 2022 07:43 AM
To: main@SDR-Radio.groups.io
Subject: Re: [SDR-Radio] Mystery mode

 

I've seen them too from southeast NH. The 'pips' are too random for QRM, I was thinking spread spectrum comms myself.
It's hard to actually listen to them, due to not appearing on the same frequency over short periods of time.

73 Kriss KA1GJU

 


GARY W RUSSELL
 

After enlarging the screen shot I see what you are talking about. I’ve actually been monitoring 14 MHz lately and have never noticed that phenomenon before here in Central, IL. I am using  SDR Console, Airspy HF+Discovery and a Wellbrook Loop antenna. I will watch for it though,
Gary


Ken Sejkora
 

Thank you, Gary.  The signal is not there all the time; it was there yesterday, Fri:08-Jul around 11:30 UTC, but wasn’t there several times when I checked this morning, Sat:09-Jul.  As stated in my original post, I usually notice it when I tune into WWV at 15 MHz, or when I’m listening to the upper part of the 20-meter band and see the blips in the waterfall above 14.5 MHz.  Given the frequency, I don’t believe it to be local to New England (Kriss up in NH often sees it as well), and is likely propagation from somewhere more distant, although CHU on 14670 kHz was coming in when I took the screenshot yesterday.  Next time I notice it, I’ll check what regions are ‘skipping’ in on 20-meters, and also check WWV and other commercial stations to get a sense of propagation while I’m seeing the mystery signal.

 

If it is some type of frequency-hopping communication mode, I’m impressed that it is spanning a frequency range of about 700 kHz.  That’s pretty big at HF frequencies, but maybe not so up in the VHF and UHF bands.

 

By the way, my monitoring here is with SDR Console, Airspy HF+ Discovery, fed from a random longwire coupled through a 9:1 unun.

 

Thanks again.  Have a great weekend.

 

Ken

 

From: GARY W RUSSELL
Sent: Saturday, July 9, 2022 09:46 AM
To: main@SDR-Radio.groups.io
Subject: Re: [SDR-Radio] Mystery mode

 

After enlarging the screen shot I see what you are talking about. I’ve actually been monitoring 14 MHz lately and have never noticed that phenomenon before here in Central, IL. I am using  SDR Console, Airspy HF+Discovery and a Wellbrook Loop antenna. I will watch for it though,
Gary

 


jdow
 

Receive them on post processing. But, then you would have to figure out how to demodulate and decrypt them. If they don't all more or less start and end at the same time you may have multiple hopping and likely encrypted nets operating.

{o.o}

On 20220709 04:43:12, Kriss Kliegle KA1GJU wrote:

I've seen them too from southeast NH. The 'pips' are too random for QRM, I was thinking spread spectrum comms myself.
It's hard to actually listen to them, due to not appearing on the same frequency over short periods of time.

73 Kriss KA1GJU


jdow
 

Roughly speaking where are you located? Are there military or protest sites anywhere near you? That definitely looks like some form of covert comm.

{^_^}

On 20220709 08:05:18, Ken Sejkora wrote:

Thank you, Gary.  The signal is not there all the time; it was there yesterday, Fri:08-Jul around 11:30 UTC, but wasn’t there several times when I checked this morning, Sat:09-Jul.  As stated in my original post, I usually notice it when I tune into WWV at 15 MHz, or when I’m listening to the upper part of the 20-meter band and see the blips in the waterfall above 14.5 MHz.  Given the frequency, I don’t believe it to be local to New England (Kriss up in NH often sees it as well), and is likely propagation from somewhere more distant, although CHU on 14670 kHz was coming in when I took the screenshot yesterday.  Next time I notice it, I’ll check what regions are ‘skipping’ in on 20-meters, and also check WWV and other commercial stations to get a sense of propagation while I’m seeing the mystery signal.

 

If it is some type of frequency-hopping communication mode, I’m impressed that it is spanning a frequency range of about 700 kHz.  That’s pretty big at HF frequencies, but maybe not so up in the VHF and UHF bands.

 

By the way, my monitoring here is with SDR Console, Airspy HF+ Discovery, fed from a random longwire coupled through a 9:1 unun.

 

Thanks again.  Have a great weekend.

 

Ken

 

From: GARY W RUSSELL
Sent: Saturday, July 9, 2022 09:46 AM
To: main@SDR-Radio.groups.io
Subject: Re: [SDR-Radio] Mystery mode

 

After enlarging the screen shot I see what you are talking about. I’ve actually been monitoring 14 MHz lately and have never noticed that phenomenon before here in Central, IL. I am using  SDR Console, Airspy HF+Discovery and a Wellbrook Loop antenna. I will watch for it though,
Gary

 


51F5A9883D9D44DFA830C7DE8C6FCFE1.png

C3C7DB19F0DD4C4F957778DF09823B48.png


Ken Sejkora
 

Thanks jdow.  I’m pretty confident that this is likely some ‘relatively new’ government/military communication mode, and most likely encrypted.  Trying to demodulate and decrypt the signal(s) is beyond what I’d try to do.  I was just curious as to what insights other users might have.  My point about recording them and looking at the waveform was more to the point of trying to see if the ‘pips’ on a given discrete frequency block are pure CW, or somehow modulated, but if they are very short in duration, that might be hard to determine.

 

As for location, I’m in SE Massachusetts (Cape Cod), so there is no shortage of potential sources within ±40-miles, such as multiple Raytheon and General Dynamics development labs, Navy facility near Newport, RI, submarine bases in Groton, CT and Portsmouth, NH, etc.  However, I’m guessing the origin might be more distant, perhaps one ionospheric skip, but hard to tell.  Kriss up in New Hampshire has also reported them.  Although he’s only ~93 miles away, it seems unlikely we’d both hear the same ‘local’ source on ~15 MHz.

 

Next time I notice them, I’ll try to get onto the Kiwi receiver network to select multiple receiver sites to se where else is ‘seeing’ them at the same time I am.  That might shed a small modicum of light on where the signals are coming from.

 

Thanks for your insights.  Have a great weekend. 73

 

Ken

 

From: jdow
Sent: Saturday, July 9, 2022 02:06 PM
To: main@SDR-Radio.groups.io
Subject: Re: [SDR-Radio] Mystery mode

 

Roughly speaking where are you located? Are there military or protest sites anywhere near you? That definitely looks like some form of covert comm.

 


jdow
 

Duration, frequency spacing, and any modulation (probably PM of some sort) would be interesting. Post processing to pull out relative timing and the like can also possibly pull out modulation using wide band USB.

{^_^}

On 20220709 14:14:56, Ken Sejkora wrote:

Thanks jdow.  I’m pretty confident that this is likely some ‘relatively new’ government/military communication mode, and most likely encrypted.  Trying to demodulate and decrypt the signal(s) is beyond what I’d try to do.  I was just curious as to what insights other users might have.  My point about recording them and looking at the waveform was more to the point of trying to see if the ‘pips’ on a given discrete frequency block are pure CW, or somehow modulated, but if they are very short in duration, that might be hard to determine.

 

As for location, I’m in SE Massachusetts (Cape Cod), so there is no shortage of potential sources within ±40-miles, such as multiple Raytheon and General Dynamics development labs, Navy facility near Newport, RI, submarine bases in Groton, CT and Portsmouth, NH, etc.  However, I’m guessing the origin might be more distant, perhaps one ionospheric skip, but hard to tell.  Kriss up in New Hampshire has also reported them.  Although he’s only ~93 miles away, it seems unlikely we’d both hear the same ‘local’ source on ~15 MHz.

 

Next time I notice them, I’ll try to get onto the Kiwi receiver network to select multiple receiver sites to se where else is ‘seeing’ them at the same time I am.  That might shed a small modicum of light on where the signals are coming from.

 

Thanks for your insights.  Have a great weekend. 73

 

Ken

 

From: jdow
Sent: Saturday, July 9, 2022 02:06 PM
To: main@SDR-Radio.groups.io
Subject: Re: [SDR-Radio] Mystery mode

 

Roughly speaking where are you located? Are there military or protest sites anywhere near you? That definitely looks like some form of covert comm.

 


Kriss Kliegle KA1GJU
 

Looks like the Maritime Mobile Net is getting hammered today!

Kriss KA1GJU


jdow
 

Putin has opened up the Soviet era jammers? That creep MUST be skinned alive.

{+_+}

On 20220710 11:15:40, Kriss Kliegle KA1GJU wrote:

Looks like the Maritime Mobile Net is getting hammered today!

Kriss KA1GJU
Screenshot-2022-07-10-141322.jpeg


Kriss Kliegle KA1GJU
 

The "pips" are active this AM. Not arriving from the south per my beam aiming south, but on EFW's, strong S-7 up here in NH.

73 Kriss KA1GJU


GARY W RUSSELL
 

Finally seeing what looks like spread spectrum mode between 14500-15100 MHz at 1620Z Faded badly by 1625Z but still there. I will post and inquiry on UDFX group to see if the source is known.

Gary
Central, IL


Ken Sejkora
 

I’m still seeing it in Massachusetts at 16:45 UTC.  I’ll check some other receivers in the Kiwi-SDR network.

 

 

From: GARY W RUSSELL
Sent: Monday, July 11, 2022 12:41 PM
To: main@SDR-Radio.groups.io
Subject: Re: [SDR-Radio] Mystery mode

 

Finally seeing what looks like spread spectrum mode between 14500-15100 MHz at 1620Z Faded badly by 1625Z but still there. I will post and inquiry on UDFX group to see if the source is known.

Gary
Central, IL