Identify HF Modes

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maca_404

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I found some of what I think is digital modes while looking around on the hf bands, I have attached some screen caps of them and was wondering if anyone has an idea of what these might be ?
 

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ka3jjz

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That first one on the left reminds me of a PSK31 signal, but you're outside the 20m ham digital portion...anyway there' s several websites that have waveforms and screen shots of digital sigs where you can compare them and make an educated guess as to what you're hearing.

Their links can be found here...

HF Digital Decoding - The RadioReference Wiki

See the 'Audio Samples of Digital Signals' section

HTH...Mike
 

Token

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In your first image (top), note that the signal at 14380 kHz and 14361 kHz have similar gaps or drops in them. This is a strong indicator of both signals being noise, not real signals. Or possibly I am not looking at the part of the screen you mean. If you mean the signal at a center frequency of 14377 kHz (presents as two lines in your image), that is 850 Hz shift FSK. The 850 Hz is a strong indicator it will be encrypted and not decodable, probably military. Most often this signal, on this frequency, has a 50 baud rate.


Same thing on the bottom image, there are multiple signals there and also some noise, so an indicator there on which signal you have a question on might help. If you mean the signal in the demodulation window, with a center frequency near 14213 kHz, you have not included enough detail to know what it is. A zoomed in shot of that might help, or an audio recording. It is possible that it is some kind of 250 Hz shift FSK, but not enough detail. It is, however, in the ham 20 meter band, so it is most likely either a ham mode or an image from outside the band, that section of the band (14213 kHz) is not normally used for digital modes.


Also note the signals on 14199 kHz and 14204 kHz, and in sync. Those rather look like PSK or something similar, again in a section of the band not normally seen, so I strongly suspect imaging, maybe PACTOR from outside the band? The lines (carriers) at 14201 kHz and 14208 kHz are obviously images around the LO spike of your SDR at 14204.4 kHz.


Circles or arrows on your image, indicating the signals you have questions about might be a good idea

What kind of SDR are you using? At a guess it is a SoftRock Ensemble II, but it really could be any sound card based SDR from the pictures you have presented.

T!

(edit) ooops, I was typing mine as Mike was posting his.
 
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maca_404

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Thanks for all the reply's, FYI yes this is a ensemble rxtx being fed to a sound blaster live and it does seem to work well. The signal which I was most interested in is the one I have centered on in the second image as I have seen it a few times. It appears to have two signals closely spaced then another off to the side I will upload a zoomed in image and a recording which may help.

Thanks again guys.
 

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Token

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I don't recognize it myself, but I am not really primarily a data modes guy. In fact, I am not seeing a data structure in it, but then the recording is too short to get much out of it.

T!
 
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