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Loggings => HF Mystery Signals => Topic started by: 5150 on January 31, 2025, 2227 UTC

Title: Digital Signals around CB channels 24 & 25 LSB - 27235Mhz and 27245Mhz
Post by: 5150 on January 31, 2025, 2227 UTC

Anybody know what these digital signals are around 27233.50 Mhz and 27236.50 Mhz LSB?  There are a lot of them.
Then there are a ton of signals around 27243.50 Mhz and 27246.50 Mhz LSB as well with a lot of traffic.   

I tried WSJTX, FLDIGI, JS8CALL, ROS, and MULTISPK but couldn't decode these, but maybe I wasn't patient enough.
Any ideas?
Thanks for any info

Title: Re: Digital Signals around CB channels 24 & 25 LSB - 27235Mhz and 27245Mhz
Post by: 5150 on February 02, 2025, 1332 UTC

Sorry to reply to myself, but I believe the signals around 27245 Mhz USB are JS8Call.   I'm running JS8Call at 27245 Mhz USB, with an offset of 2500Hz (variable) and have managed to decode a few of these.   So if you're interested - JS8Call seems to be alive and well on the CB channels.

Title: Re: Digital Signals around CB channels 24 & 25 LSB - 27235Mhz and 27245Mhz
Post by: Robot Matrix on February 04, 2025, 2303 UTC

WOW! Great catch! I'll have to download that and try it.

Title: Re: Digital Signals around CB channels 24 & 25 LSB - 27235Mhz and 27245Mhz
Post by: alain on July 19, 2025, 1552 UTC

I bet you are hearing AX25 (FM) from Germany.

Looks like there quite a vibrant AX25 revival specifically on those frequencies. For example, this one is on 27.235 FM: https://lk0nod.de/

The stations are numerous and - skip permitting - they appear from time to time mixed with other traditional voice traffic.