Hi Mike, Thank you very much! I thought I had selected "No" to Differential Encoding. Either way, I wanted to do both, just that I thought it would be easiest to start out without Differential Encoding (trying for the lower hanging fruit and messed up).
Thank you very much! I will give it a try and provide feedback. Best Regards, George On Fri, Mar 12, 2021 at 8:23 PM Mike Markowski <mike.ab...@gmail.com> wrote: > Hi George, > > You used differential encoding but forgot differential decode. I added > the block in the attached. (I disabled your file creation and displayed > to gui, easier for me to check.) > > Little things are the hardest to spot. :-) > > Mike Markowski > > On 3/12/21 4:46 PM, George Edwards wrote: > > Hi Mike, > > > > Thanks for your help! > > > > As I mentioned in my email, my flowgraph consists of some of the blocks > > in the example. I dropped some of the blocks because I am doing concept > > testing to ensure I know how to set parameters for the blocks. In > > terms of delays, that is not a problem. I am dumping the outputs into 2- > > file sinks, so in post processing I can compensate for that. The problem > > is that the tx and rx data are not the same, so I am missing in setting > > parameters. > > > > Thanks again! > > George > > > > On Fri, Mar 12, 2021 at 3:31 PM Mike Markowski <mike.ab...@gmail.com > > <mailto:mike.ab...@gmail.com>> wrote: > > > > I can't make out details in your image, George, but attach one I made > > when working through the tutorial and works just now under gnuradio > > 3.8.1.0. Like someone else mentioned in another reply, I found the > > delay to be 58 and set it as the default in the attached flowgraph. > > Zoom in on the bit stream plot and allow a second or two after > changing > > delay to see the effect. > > > > Hope this helps, > > Mike Markowski > > > > On 3/12/21 10:37 AM, George Edwards wrote: > > > Hello, > > > > > > I cannot get the combined Constellation Modulator/Decoder as > > shown below > > > to work. The figure below is an example from the online Guided > > Tutorial > > > PSK Demodulation.... I leave out the Equalizer, Costas Loop > > blocks, the > > > channel was set to pass the signal unimpaired and the Poly Clock > > Sync > > > was set for Output sps=1. The constellation plot of the output of > > the > > > Poly Clock Sync is perfect. Now, in the flowgraph below, the > signal > > > entering the Constellation Modulator and that leaving the > > Constellation > > > Decoder are routed into Time Sinks for display. I route these > > signals > > > into File Sinks so I can print them and compare 1's and 0's. The > > results > > > show they are not the same. I passed Constellation Rect.Object > > > parameters to both the Constellation Modulator and Decoder, which > > seems > > > logical to me, but I could be wrong??? > > > Will appreciate any help you can provide because what enters the > > > modulator should be the same as what is leaving the demodulator. > > > Regards, > > > George > > > > > > image.png > > >
