Re: [Discuss-gnuradio] trouble with QAM mod/ WX GUI Constellation Sink

[Tom Rondeau]

On Fri, Jul 17, 2015 at 12:23 PM, Martin Braun <address@hidden> wrote:

On 17.07.2015 05:35, Sylvain Munaut wrote:
> AFAIK the constellation sink just can't do QAM.
>

Yeah, and personally I've always doubted the utility of a dedicated
constellation sink (guess what, it's gone in QT). The reason being, if
the GUI widget has it's own demod chain, you're always plotting
something that's unavailable elsewhere in the flow graph.

My preference is to build the demod/sync chain with it's own blocks, and
then just output the complex symbols into either an X/Y plot (WX) or the
QT Constellation Sink. This way, you have better control over the
timing, phase etc. recovery.

And, in your case, you can actually start with baby steps. So you can
start by testing your QAM mapper directly with the graphical sink. Then,
as you add stuff, you can how well e.g. the timing recovery is working.
Makes sense?

M

I agree with Martin here; I was always unhappy with that constellation sink trying to do too much. It'd be fine if we had a universal synchronizer :)

Tom