Talk:DNA-like shifting frequencies signal
i seen the same, location: mediterranean, turkey. my opinion it's a feedback from atmosphere.
This is probably the weirdest signal ive ever seen. I think there is transmitter issues causing the mirrored images, also causing it (maybe) to "flank".
Ywsia1.--TALK
mirror images means your receiver is overloaded which means the signal is too strong ... which means it is probably nearby. if you use an attenuator (a real HW in line with the antenna or a software one) the mirror images should disappear.
Mela -- TALK
This is a common misconception, but I never had the time to really explain these signals. Basically this is a simple FMFrequency Modulation transmission that very likely uses either CTCSS or DCS, and the receiving user has selected a FFT bin size that somehow matches the frequency shifting harmonics to create this helix shape. I have before recreated this using low FFT bin sizes and monitoring DCS and CTCSS-enabled FMFrequency Modulation radio transmissions. --Cartoonman (talk) 01:41, 31 August 2017 (NZST)
That is very interesting. Do you think you could get a recording? Willt (talk) 03:02, 31 October 2017 (NZDT)
I havent tested it, but try downloading the IQQuadrature signals form the basis of complex RF signal modulation and demodulation, both in hardware and in software, as well as in complex signal analysis. from this: https://www.sigidwiki.com/wiki/Continuous_Tone-Coded_Squelch_System_(CTCSS) and setting the FFT bin size to something low like 2048 or 512 or so. You might get the helix. If not, it's prob DCS that does it, but I currently have not done DCS article yet. I have the samples somewhere, just never got around to it. --Cartoonman (talk) 16:44, 2 November 2017 (NZDT)
This is way, WAY too wide to be CTCSS/DCS. Signal bandwidth is nearly 180kHz, check the second screenshot provided. I do agree this is an oscillating FMFrequency Modulation signal, but I believe it is simply interference. That would explain multiple copies of the signal on the band. The regularity of each signal implies there is no information being transmitted.
DCS doesn't leave a helix, but leaves two distinct peaks. It doesn't have the same regularity of CTCSS. --Kj6psg (talk) 19:23, 27 September 2018 (NZST)
