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I am wanting to read radio signal I captured with my RTL-SLR, I record it in .wav file using SDR#, The Frequency was at 315MHz. I am what I believe is the preamble of the signal, and I would like feedback if I am reading it correctly.

enter image description here

I also put the wav file into hexviewer, and assuming I read it correctly, I did not find binary pattern based on what I saw in audacity, does that even matter or no?

Also I measure the μs between 1, and 000, for 1 I got 150μs, and for 000, I measured 460μs. I am not sure if I am accurate on that. For some reason I decided to divide 150/460, and got 3.06 (close enough to whole number) that is why I assume its 000.

My question is, To figure out binary of RF signal am I doing it correctly or what do I need to do?

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  • \$\begingroup\$ You're doing something that's consistent with the signals you can see on screen at the moment. Is it correct? Who knows? Perhaps you need to do some research on the origins of the signal. Reverse engineering meaning from a signal involves making assumptions, and then testing them. So far, looks OK. \$\endgroup\$ – Neil_UK Feb 27 '18 at 6:59
  • \$\begingroup\$ You won't see a binary pattern in the hex file (and you forgot to mention what format the file is) because the signal is not binary - it is analog. The values at each reading will depend on where in the cycle they were measured. You can see on the trace that there are readings between max and min. Also the file is probably a compressed format. \$\endgroup\$ – Transistor Feb 27 '18 at 7:04
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    \$\begingroup\$ There is not point in talking about a binary pattern of a RF signal if you don't specify what modulation is used. Although the signal looks amplitude modulated, who knows, maybe it's PSK and the amplitude variation that can be seen is completely unrelated to the actual signal. \$\endgroup\$ – Curd Feb 27 '18 at 8:10
  • \$\begingroup\$ In sdr# I would rebroadcast the signal, I never saw frequency shift, it was fixed on one frequency, could that mean that it is using AM? \$\endgroup\$ – user1884552 Feb 27 '18 at 11:53
  • \$\begingroup\$ Update, I took a look at the signal, and modulation looks more like FM. \$\endgroup\$ – user1884552 Feb 27 '18 at 16:07

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