Unknown Looking for a type of digital decoding software

[musiclistener]

The signal is constant on 10.155 Mhz. No luck with sound bites of digital modes on the internet. Any help would be great. Thanks.

 

[air-scan]

The signal is constant on 10.155 Mhz. No luck with sound bites of digital modes on the internet. Any help would be great. Thanks.

Post a screen shot if you're seeing it on a SDR. Record a video of it if it's a portable or a desktop radio or just record a 10 second clip of the signal then post it. That'll help people help you.

That frequency is just 5khz above the 30m amateur band. It'll help to find out what 10.155MHZ is allocated for.
Scroll down to the bottom of page 10 in this FCC pdf document fcctable.pdf

This page Tuning 150 kHz to 30 MHz (dxing.com) also is good.

10150 to 11175 kHz: This segment is used by fixed stations. In addition to various FSK and digital modes, you may hear several international broadcast stations being relayed in SSB. These "feeder" stations are used to send programming to relay sites not served by satellite downlinks.

 

[ka3jjz]

With an actual center of 10153, a likely candidate is a NATO modem from Isabela Puerto Rico. Nothing you can get can decode this.

Undecodeable NATO Digital Signals - The RadioReference Wiki

wiki.radioreference.com

Mike

 

[musiclistener]

I have added a sound bite of the digital sound that I am looking to decode

 

[air-scan]

I have added a sound bite of the digital sound that I am looking to decode

That's N.A.T.O. or Military FSK which sort of sounds like RTTY. Maybe ARQ-E or N not sure. It's also encrypted. No way to decode it except maybe the headers which is quite boring. Sounds like 850bd which is very wide as compared to ham radio RTTY at 45bd which is decodable.

I have heard this in the evening on 6487usb, 4007usb, and daytime 15959usb. Their are many more frequencies they use on the HF bands. I don't keep up with those.

 

[ka3jjz]

If you adjust 4007 to 4005 (the other 2 freqs are correct), you will find the sites (found by TDoA) identified on the wiki article I mentioned in message 3 of this thread...Mike

 

[air-scan]

If you adjust 4007 to 4005 (the other 2 freqs are correct), you will find the sites (found by TDoA) identified on the wiki article I mentioned in message 3 of this thread...Mike

Might want to check again seems they changed recently.

 

[ka3jjz]

If you know which ones changed - certainly possible - feel free to go into it and make the corrections

Mike

 

[air-scan]

If you know which ones changed - certainly possible - feel free to go into it and make the corrections

Mike

Done it but I fully understand someone else may edit it back. If they do they really should check 4005 did switch to 4007.

 

[ka3jjz]

The list comes from the UDXF (Utility DXers Forum) reflector on groups.io. That's likely the best place to ask such a question. Mike

 

[ka3jjz]

Going thru the last 5 months worth of logs, 4005 seems to have some stability issues, wandering up to +2 khz from nominal 4005 from time to time. And it also appears that the mode is STANAG 4481,

STANAG 4481 - Signal Identification Wiki

STANAG 4481, also known as CRATT, Link-4, and NATO-75, is specified by the NATO (North Atlantic Treaty Organization) Military Agency for Standardization as a "Minimum technical equipment standards for naval HF shore-to-ship broadcast system"

www.sigidwiki.com

I will make a note of this on the article

Mike

 

[ka3jjz]

The article in message 3 has now been updated with 5 months worth of logs (Jan-May 2021). Changes are in italics and notes are inserted where a frequency has evidently slipped

Mike

 

[air-scan]

Well that explains it. Thanks.