Hi Ron,
Thank you for that tx grc graph, it is super helpful!
I am just trying to get a receive work now. I am using the 6_psk.grc from the tutorial folder in the github repo you were using [1].
I have modified mine for using a hackrf on tx side and on rx side I modified to use the same sample rate and freq as your tx graph. I added a slider to help tune in to the freq, but I haven't had luck decoding yet - did you have a working rx graph you were using for testing?
Thanks again! :-)