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I saw a strange signal on the WSJT-X waterfall this evening and have no idea what mode it is, so I am here to check with others.
Band in use at the time was 30M, (so 10.136.00 MHz,) while on FT8 mode and the strange signal signal occupies about 100Hz of bandwidth starting at 880Hz.
Have a look at the image below and submit your suggestions...
Doug VK4ADC @ QG62LG51
http://www.vk4adc.com
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From the picture it looks like FSK with eight tones.
https://www.sigidwiki.com/wiki/Category:Amateur_Radio Perhaps some sort of MFSK-8 or a faster FT8/JT8 variant being tested.
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Maybe but in the picture the tone spacing looks like using K = 2 and the bandwidth is 150 Hz. The one from Doug looks like K = 1. It could also be the n'th harmonic of a signal.
Unfortunately, I don't know of a any public programs with automatic protocol detection and decoding - it would indeed be nice to have.
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Bo
I looked through that table and it doesn't match up with anything there. I only have the original screen shot but have done a 250% blow-up of part of it below, with a normal FT8 emission just to the RHS.
The bandwidth is obviously 100 Hz, structure at 8 frequency streams (very obvious in the base spectrum display). The data rate looks to be similar to that of FT8.
So still an "i don't know" .... Maybe it is a new mode being tested - right in the middle of the designated FT8 "band".
Doug VK4ADC @ QG62LG51
http://www.vk4adc.com
This Forum is only going to be as interesting as the posts it contains.
If you have a comment or question, post it as it may trigger or answer the query in someone else's mind.
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It looks FT8'ty. There seem to be two sync frames. One at the beginning and one at the end. I cannot see if there is anything in the middle.
If you hear it again you may try to log it using Spectrum Lab
https://www.qsl.net/dl4yhf/spectra1.html to get a much closer view on things.
Not all modes are in the linked signal wiki.
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Hello Doug, looks like audio harmonics from someone with audio over-drive on a lower part of the FT8 segment, have seen this a bit on 40mx FT8 when stations get over excited...
