Very slow very narrow mode

[MM6LKX]

Stumped on this one. Some sort of beacon? Here is a waterfall from WSJT-X in the course of WSPRing. Dial frequency is 7038.6, two-minute WSPR transmissions visible in a band 1400 Hz-1600 Hz above that. I am looking at the longer transmissions at 1190 Hz and 1310 Hz. 1190 repeats every 50 mins, 1310 every 10 mins. Each consists of slow alternation between two tones about 5 Hz apart, with each individual tone lasting several seconds. 1310 has another feature at end of transmission, a set of slow chirps and beeps. What could it be? I have audio.

 

[W1HD]

Is this running 24/7?

 

[merlin]

Low end looks like a single call FT8. Next up, a chain of FT8 messages. Then your WSPR above that.
WSJT-X is typical for decoding but you have to note, timing and time is very critical.

 

[MM6LKX]

Low end looks like a single call FT8. Next up, a chain of FT8 messages. Then your WSPR above that.
WSJT-X is typical for decoding but you have to note, timing and time is very critical.

Time and frequency structure are not FT8.

Is this running 24/7?

I don't know about the 7 but the 24 is possible from my 2-day sample. Here in grid IO84 I am seeing it dawn-dusk, which should probably tell me something about the path. You can probably see it http://websdr.ewi.utwente.nl:8901/ not too far from me. Having actually looked at that site myself just now, it has lookup of known stations marked along the frequency axis and it looks like it may be something to do with some Czechs (OK0EPB, OK0EU) who are into weird time signals and Doppler sounding, although neither the timing nor the frequency are exactly these.

 

[merlin]

Agree the timing is not FT8, so may be some adaptation of a similar protocol.
In the 40 meter band and FT8 calling frequency led me to suspect.
50 Hz shift/ Tx 15 seconds/ Rx 15 seconds it will decode as FT8.

 

[MM6LKX]

Once I fiddle about making suitably legible spectrograms it turns out to be: Morse, just very slow and with a 5 Hz shift instead of on-off. Content is just call sign, and the fuzzy blob at the end is the call signed Hellschreibed. Two UK users.

 

[merlin]

Once I fiddle about making suitably legible spectrograms it turns out to be: Morse, just very slow and with a 5 Hz shift instead of on-off. Content is just call sign, and the fuzzy blob at the end is the call signed Hellschreibed. Two UK users.

Seen that before too.