Hi Fabian, Thank you for the reply. Actually, I am just starting to learn the ins and outs of GNU Radio and SDR. I will try to increase the cutoff and max deviation and check the results. With regards to the Fractional BW at TX, I just copied it from some code I found online. Should I change it to a different value? *sorry, i am still trying to absorb all the concepts*
Regards, Bryan On Thu, Jun 24, 2021 at 4:58 PM Fabian Schwartau <[email protected]> wrote: > Hi Bryan, > > I just noticed a few things I am not sure about. Maybe I got something > wrong, maybe they are a mistake: > You transmit at 70cm and receive at 2m. > You use a low-pass filter with 5kHz cutoff and allow a maximum deviation > of 5kHz of the NBFM receiver. I am not sure, but I think this is not > optimal. I would expect a spectrum quite a bit wider than 5kHz when > transmitting with 5kHz max deviation. > Why is the fractional BW of your Rational Resampler in the TX path 0? > > Best regards, > Fabian > > Am 24.06.21 um 08:19 schrieb bryan: > > Hi, > > I have this flowgraph programmed in two b200 SDRs. I want to > > communicate via ax.25. The problem is both are not consistent in > > receiving data from each other. It is like for every 10 transmitted > > data, around 5 are received from the other end. Can anybody tell me what > > I did wrong so that the two SDRs will communicate consistently? Note > > that both of them are just located very near to each other? Here is my > > flowgraph: > > > > RX: > > image.png > > > > TX: > > > > image.png > > > > Regards, > > Bryan > > >
