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Author Topic: HF oddities to SigID Wiki  (Read 214 times)

Offline northern_dxer

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HF oddities to SigID Wiki
« on: June 23, 2024, 1544 UTC »
Hi all,

I have encountered several strange signals while browsing the HF and low VHF spectrum. I have collected them to SigID wiki and I thought that people on this forum might be able to identify them. If these can be identified, they can be renamed and sorted in the wiki.

All have been recorded in northern Europe and in many cases I have added links to videos or sources made by other people who have seen these.

1. MFSK-11 data mode, very similar to XPB and other supposedly Russian modes. Should we just call this "CIS MFSK-11" until we have a better name?

2. Unknown data mode on the low VHF band. Already suspected to be Mobitex but this has not been confirmed.

3. Unknown data mode on HF, transmitted in bursts.

4. A supposedly Russian data mode with very interesting spectrum pattern. According to other sources, it uses OFDM for data transmission. There are also MFSK and frequency sweeps. Is there an official or a commonly agreed name for this?

5. Slow sweeping FMCW radar on many bands, appeared in 2024. Marine research or military?

6. Lower HF band radar, some similarities with CODAR but still quite different.

7. Weak HF radar with 48 kHz bandwidth, unfortunately no better sample available.

8. Low VHF band radar with pulsed transmission. Military OTH/long range radar?

9. Narrow FMCW radar on low VHF. No distinguishing features.

10. Sweeping (stepping) HF sounder, similar to Digisonde but has some differences. Seems to transmit 40 Hz pulses. Is this just Digisonde? 

11. Strange data mode or jammer? Resembles CIS-12 and similar data signals, but is often found on broadcast frequencies and looks rather messy with an ambiguous number of tones. A similar but weaker and less "messy" signal has been spotted on the "UVB-76" frequency lately.

12. Low VHF band radar with more or less irregular pulse pattern. A research radar perhaps?

13. Another low VHF band suspected research radar, this time with regular pulse pattern.

14. Likely HF FMCW radar with 120 Hz sweeprate.

15. Wideband pulsed HF radar-like signal that starts with a slower pattern



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