GFSK modulation experiments

Quadcopter I use is having a 3DR Radio Telemetry which uses Si4432 Radio Module which uses GFSK modulation. So here is a small experiment with generated Sine wave to get familiar with GRC blocks to modulate, demodulate.

Here is the flow graph:




Here are the screen shots of GFSK modulated and demodulated Sine wave, achieved by editing the flow graph by inserting output blocks:






 Then I saved the demodulated data to view this in Baudline. The waveform displayed in baudline is:



 



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