[Discuss-gnuradio] Changing interp rate dynamically?

[Michael Dickens]

I've created an "analog repeater" that's just:

usrp source -> amp -> usrp sink

and I'd like to control the "bandwidth" that's repeated  
dynamically ... on the fly via a GUI slider.  I have created all of  
this, and on init everything works just fine.  But the moment I  
change the bandwidth value to -anything-, including the original  
values, the TX stops.

I'm also displaying the output of the 'amp' on a waterfall scope, so  
I can see that the USRP source is generating data all of this time.   
It seems like the decim rate of the source is being changed properly.

I've tracked this down through Python and C++, and everything looks  
OK .. nothing else is touched in the process of setting the sink's  
interp rate.  In usrp_standard_tx::set_interp_rate, an FPGA register  
is changed to reflect the new interp rate; I haven't tried tracking  
down that side of things, since I've never investigated FPGA code and  
really don't have time to right now.

Hence the question for folks who hopefully know better: Can the  
interp rate be changed dynamically ... after its original init?  I  
should think this would be OK, but obviously it's not working for  
me.  Thanks in advance! - MLD