Re: communication of two b200 via ax.25

[Fabian Schwartau]

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