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Loggings => HF Mystery Signals => Topic started by: SM5003SWL on March 29, 2024, 1209 UTC

Title: What kind of OTH radar could this be..
Post by: SM5003SWL on March 29, 2024, 1209 UTC

Got this signal around 6255kHz a couple days ago which sounded like a faster version of the Duga but it has some differences compared to other OTH radars I've noticed..
Besides the fast pulses it also had a carrier at 600Hz, and a subset of under and overtones from ~2600-3200Hz.

https://vocaroo.com/14cJp8IeOGq3

Besides that the pulses also momentarely stopped however the carriers remained...

(https://i.imgur.com/XO1u9SS.png)

(https://i.imgur.com/CXyudFc.png)

Does anyone know which system causes these particular signals?
Cheers! //Greg.

Title: Re: What kind of OTH radar could this be..
Post by: Token on March 29, 2024, 1849 UTC

This is not an OTHR.

I don't know what it is, specifically, but for a variety of reasons (features of or missing from the signal) I know it is almost certainly not a radar.  Or if it is (since almost any signal can be) a radar it is an extraordinarily poorly designed one.  I suspect it is data of some kind, but to get a better handle on what it is would require a different recording, preferably an IQ recording or an audio recording in FM or SSB (I prefer USB) that captures both "carriers" and everything between them.

T!