[Discuss-gnuradio] portaudio sink updated, fm stereo receive with pa added

[Robert McGwier]

After offline discussions with Eric, Frank, and Stephane we decided to 
check the portaudio sink with 10.66666... msec buffers and fixed 
latency.  That code has been checked in and there are a few ways to test it.

In gnuradio-examples/python/audio:

multi_tone_portaudio.py is multi_tone but enabled for portaudio
mono_tone_portaudio.py is mono_tone (single channel) for portaudio

In gnuradio-examples/python/usrp:

usrp_wfm_rcv_pll_PA.py

is the stereo FM receiver with the portaudio sink.

All of these were tested here on 4 systems with alsa, oss, and jack and 
with the ring buffers operating on a power of 2 size and fixed small 
latency request,  the sink seems solid.  No glitches, no pops, no underruns.

Bob

--
AMSAT VP Engineering. Member: ARRL, AMSAT-DL, TAPR, Packrats,
NJQRP/AMQRP, QRP ARCI, QCWA, FRC. ARRL SDR Wrk Grp Chairman
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