Hello.
I’m quite new to both SDR and Gnuradio an have been learning by exploring naive simulations. I recently decided to simulate an FSK modulation scheme with a constant source, a noice source and 2 time sinks. The first time sink is pre-modulation and the second is post-modulation. When I first start the simulation, both time sinks display the same waveform as expected. When I add a strong noise signal in real time via a GUI entry the post-modulation time sink displays a randomly changing waveform again, as expected. However, when I reduce the noise source to 0, the post-modulated sink stabilizes to match the pre-modulated sink except that it is translated arbitrarily to the left or right. this causes an arbitrary byte to be spit out when the bits are repacked. I’m sure I’m missing some basic concept that will make this make sense. can someone point me to my oversight? Thank you.
I’ve attached screenshots of my flow graph and the sink outputs.
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