Hi Brady, David, Thank you very much for sharing the GRC flowgraphs. This will help me a lot setting up a similar test. Regarding the performance, I was just surprised to see such a big difference between a modem which runs through analog FM and your new modem. I would have expected something in the range of 6-10 dB, not 16-20 dB. Maybe I need to calibrate my signal again. I enjoyed a lot reading about the experiment on your blog David. It seems like a new revolution for VHF/UHF weak signal work.
73, Adrian (YO8RZZ) On 3/17/16, Brady O'Brien <brady.obrien...@gmail.com> wrote: > Hey Adrian, > > The gnuradio-companion pipelines I used for the test are attached. These > grc pipelines are only meant to get 16-bit 48k samples in and out of the > HackRF and rtlsdr for testing. The meat of the FSK is done with the C fsk > modem, used in freedv_rx, freedv_tx, fsk_mod, and fsk_demod. We are also > running our FSK modem directly from SDR samples instead of through FM > radios. We will be running 2400B over legacy FM radios, but don't yet have > the same degree of test coverage. > > Thanks, > > Brady O'Brien > > On Wed, Mar 16, 2016 at 3:34 PM, Adrian Musceac <kanto...@gmail.com> wrote: > >> Hi David, >> >> Is it possible to get our hands on the Gnuradio code? I've been trying >> to optimize modems running at 1200 bits/second and the best I could do >> was 100% copy at 8 dB above analog FM for DBPSK and 12 dB above for >> GMSK. Your modem seems to be 16-20 dB better than that! If I could see >> the Gnuradio graph maybe I could figure out what I'm doing wrong. >> >> Thanks, >> Adrian >> >> On 3/16/16, Steve <coupaydevi...@gmail.com> wrote: >> > Ha, I wish it was through a radio! >> > >> > I'm trying to think what I have laying around here that might make a >> > good >> > transmitter for it. >> > >> > On Wed, Mar 16, 2016 at 4:02 AM, glen english <g...@cortexrf.com.au> >> wrote: >> > >> >> ah. good stuff. nice progress. >> >> >> >> >> >> On 16/03/2016 7:50 PM, Steve wrote: >> >> >> >> Just using the script: >> >> >> >> freedv_tx 2400A ve9qrp_10s.raw modem.raw >> >> >> >> Which produces a RAW audio file sampled at 48 kHz and importing that >> into >> >> audacity. >> >> >> >> On Wed, Mar 16, 2016 at 3:46 AM, glen english <g...@cortexrf.com.au> >> >> wrote: >> >> >> >>> Hi Steve >> >>> >> >>> Nice >> >>> >> >>> is that through a PA- if so, linear or linear in say 3dB compression? >> >>> >> >>> >> >>> On 16/03/2016 7:42 PM, Steve wrote: >> >>> >> >>> Thought I'd upload a spectrum snapshot. You can't really see the >> >>> carriers >> >>> until you drop the number of samples to about 256, but this shows how >> >>> wide >> >>> it is. >> >>> >> >>> I noticed that the freedv_tx was outputting +/- 1.0 signals and a >> couple >> >>> of clips going on. Maybe need to knock it down to +/- .5 like the old >> >>> FDM >> >>> modes. >> >>> >> >>> FYI >> >>> >> >>> Steve >> >>> >> >>> >> >>> >> >>> >> ------------------------------------------------------------------------------ >> >>> Transform Data into Opportunity. >> >>> Accelerate data analysis in your applications with >> >>> Intel Data Analytics Acceleration Library. >> >>> Click to learn >> >>> more.http://pubads.g.doubleclick.net/gampad/clk?id=278785231&iu=/4140 >> >>> >> >>> >> >>> >> >>> _______________________________________________ >> >>> Freetel-codec2 mailing >> >>> listFreetel-codec2@lists.sourceforge.nethttps:// >> lists.sourceforge.net/lists/listinfo/freetel-codec2 >> >>> >> >>> >> >>> >> >>> >> >>> >> ------------------------------------------------------------------------------ >> >>> Transform Data into Opportunity. >> >>> Accelerate data analysis in your applications with >> >>> Intel Data Analytics Acceleration Library. >> >>> Click to learn more. >> >>> http://pubads.g.doubleclick.net/gampad/clk?id=278785231&iu=/4140 >> >>> _______________________________________________ >> >>> Freetel-codec2 mailing list >> >>> Freetel-codec2@lists.sourceforge.net >> >>> https://lists.sourceforge.net/lists/listinfo/freetel-codec2 >> >>> >> >>> >> >> >> >> >> >> >> ------------------------------------------------------------------------------ >> >> Transform Data into Opportunity. >> >> Accelerate data analysis in your applications with >> >> Intel Data Analytics Acceleration Library. >> >> Click to learn >> >> more.http://pubads.g.doubleclick.net/gampad/clk?id=278785231&iu=/4140 >> >> >> >> >> >> >> >> _______________________________________________ >> >> Freetel-codec2 mailing >> >> listFreetel-codec2@lists.sourceforge.nethttps:// >> lists.sourceforge.net/lists/listinfo/freetel-codec2 >> >> >> >> >> >> >> >> >> >> >> ------------------------------------------------------------------------------ >> >> Transform Data into Opportunity. >> >> Accelerate data analysis in your applications with >> >> Intel Data Analytics Acceleration Library. >> >> Click to learn more. >> >> http://pubads.g.doubleclick.net/gampad/clk?id=278785231&iu=/4140 >> >> _______________________________________________ >> >> Freetel-codec2 mailing list >> >> Freetel-codec2@lists.sourceforge.net >> >> https://lists.sourceforge.net/lists/listinfo/freetel-codec2 >> >> >> >> >> > >> >> >> ------------------------------------------------------------------------------ >> Transform Data into Opportunity. >> Accelerate data analysis in your applications with >> Intel Data Analytics Acceleration Library. >> Click to learn more. >> http://pubads.g.doubleclick.net/gampad/clk?id=278785231&iu=/4140 >> _______________________________________________ >> Freetel-codec2 mailing list >> Freetel-codec2@lists.sourceforge.net >> https://lists.sourceforge.net/lists/listinfo/freetel-codec2 >> > ------------------------------------------------------------------------------ Transform Data into Opportunity. 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