Hi Ashkay, Not sure what the cause is, will look into it over the next few days. It may be different to the noise you are experiencing as it is only on 700C.
Cheers, David On 28/01/17 19:42, Akshay Mishra wrote: > Sorry to hijack thread, what is the cause of the /helicopter noise. /I > observe this occasionally also in my implementation on the STM32 which > is derived from the stm32 code. It has been interfaced with a IoT radio > and I intend to make it available pretty soon however this helicopter > noise is a source of irritant. Initially I thought the it is RFI but > shielding also did not solve it completely. > > best, > Akshay > > > On 28 January 2017 at 09:57, David Rowe <[email protected] > <mailto:[email protected]>> wrote: > > Just had a 30 minute QSO with a local Ham (vk5apr) on 7.177MHz using > 700C. Peter has the Windows version, I have a Linux version of FreeDV, > > Few little issues I'll look into, like helicopter noises with 700C in > analog mode, and providing a BER estimate. > > Our consensus was not as good at 1600, but still quite usable for a > conversation. > > We pushed the power level right down until we hit 0dB SNR at which point > the audio started to become unintelligible. At this level the modem > tones were quite down in the noise when listening in analog mode. SSB at > roughly the same level was a 100% copy but noisy. Although hard to > compare power levels exactly. > > Next step - would like to try it on a channel with fading. > > Cheers, > > David > > On 28/01/17 07:57, Helmut wrote: > > Thanks David, I'll check the test waves tomorrow. > > > > 73, Helmut > > > > -----Ursprüngliche Nachricht----- > > Von: David Rowe [mailto:[email protected] <mailto:[email protected]>] > > Gesendet: Freitag, 27. Januar 2017 20:46 > > An: [email protected] > <mailto:[email protected]> > > Betreff: Re: [Freetel-codec2] FreeDV 700C early release > > > > Hi Helmut, > > > > Hmm, that's a mystery but maybe I have missed something. I can > run 700c > > between linux and windows machines here on the bench. I have a report > > from others running the SVN release below OK. > > > > Do the 700c/800xa test wave (links below) files decode for you? > > > > Thanks, > > > > David > > > > On 28/01/17 05:26, Helmut wrote: > >> Hi David, > >> > >> Together with my friend Alfred, HB9EPU, I started today a first > trial with > >> early freedv-windows-2996. Alfred used svn 2978 in his particular > > Linux/SDR > >> environment. As the test of mode 700C failed, I easily selected > mode 700B > >> while Alfred had to move over to 700B using now svn 2299. All > worked fine > > as > >> experienced in the past. > >> Double check back to 700C: same failure. > >> > >> Any ideas, why 700C didn't work? Was there any modification of > the modem > >> features? > >> > >> 73, Helmut, DC6NY > >> > >> > >> -----Ursprüngliche Nachricht----- > >> Von: David Rowe [mailto:[email protected] <mailto:[email protected]>] > >> Gesendet: Donnerstag, 26. Januar 2017 06:45 > >> An: [email protected] > <mailto:[email protected]> > >> Betreff: [Freetel-codec2] FreeDV 700C early release > >> > >> Over the past few months I've been working on a new 700C bit/s speech > >> codec. The idea is to make it roughly the same quality as the FreeDV > >> 1600 mode but at a lower bit rate so it can punch through HF channels > >> better. > >> > >> I had a huge response to a recent blog post on the 700C codec: > >> > >> http://www.rowetel.com/?p=5373 > >> > >> We now have an early version of the FreeDV GUI program for Windows > >> available, that runs "FreeDV 700C": > >> > >> http://rowetel.com/downloads/freedv-windows-svn-2996.tar.gz > <http://rowetel.com/downloads/freedv-windows-svn-2996.tar.gz> > >> > >> Richard is also working on a version with a proper installer, but > in the > >> meantime I'd welcome any feedback on 700C/800XA. > >> > >> I can't guarantee the bit stream will be stable (hence the early > release > >> tag), but I'll let people know if it changes. > >> > >> As a bonus it also supports the "800XA" mode developed by Brady - > which > >> is the 700C codec with a FSK modem. FSK lets you push a bit more > power > >> through your PA than the normal PSK modem used for FreeDV 700C. It > >> might also let the smoke out of your SSB PA so pls be careful. > >> > >> Here are some wave file you can use to test 1600/700C/800XA: > >> > >> http://rowetel.com/downloads/codec2/ve9qrp_1600.wav > <http://rowetel.com/downloads/codec2/ve9qrp_1600.wav> > >> http://rowetel.com/downloads/codec2/ve9qrp_700c.wav > <http://rowetel.com/downloads/codec2/ve9qrp_700c.wav> > >> http://rowetel.com/downloads/codec2/ve9qrp_800xa.wav > <http://rowetel.com/downloads/codec2/ve9qrp_800xa.wav> > >> > >> Play them into FreeDV using the "Tools-Start/Stop Play File from > Radio" > >> option. > >> > >> Thanks, > >> > >> David > >> > >> > > > > ---------------------------------------------------------------------------- > >> -- > >> Check out the vibrant tech community on one of the world's most > >> engaging tech sites, SlashDot.org! http://sdm.link/slashdot > >> _______________________________________________ > >> Freetel-codec2 mailing list > >> [email protected] > <mailto:[email protected]> > >> https://lists.sourceforge.net/lists/listinfo/freetel-codec2 > <https://lists.sourceforge.net/lists/listinfo/freetel-codec2> > >> > >> > >> --- > >> Diese E-Mail wurde von Avast Antivirus-Software auf Viren geprüft. > >> https://www.avast.com/antivirus <https://www.avast.com/antivirus> > >> > >> > >> > > > > ---------------------------------------------------------------------------- > > -- > >> Check out the vibrant tech community on one of the world's most > >> engaging tech sites, SlashDot.org! http://sdm.link/slashdot > >> _______________________________________________ > >> Freetel-codec2 mailing list > >> [email protected] > <mailto:[email protected]> > >> https://lists.sourceforge.net/lists/listinfo/freetel-codec2 > <https://lists.sourceforge.net/lists/listinfo/freetel-codec2> > >> > > > > > > ---------------------------------------------------------------------------- > > -- > > Check out the vibrant tech community on one of the world's most > > engaging tech sites, SlashDot.org! http://sdm.link/slashdot > > _______________________________________________ > > Freetel-codec2 mailing list > > [email protected] > <mailto:[email protected]> > > https://lists.sourceforge.net/lists/listinfo/freetel-codec2 > <https://lists.sourceforge.net/lists/listinfo/freetel-codec2> > > > > > > --- > > Diese E-Mail wurde von Avast Antivirus-Software auf Viren geprüft. > > https://www.avast.com/antivirus <https://www.avast.com/antivirus> > > > > > > > > ------------------------------------------------------------------------------ > > Check out the vibrant tech community on one of the world's most > > engaging tech sites, SlashDot.org! http://sdm.link/slashdot > > _______________________________________________ > > Freetel-codec2 mailing list > > [email protected] > <mailto:[email protected]> > > https://lists.sourceforge.net/lists/listinfo/freetel-codec2 > <https://lists.sourceforge.net/lists/listinfo/freetel-codec2> > > > > > ------------------------------------------------------------------------------ > Check out the vibrant tech community on one of the world's most > engaging tech sites, SlashDot.org! http://sdm.link/slashdot > _______________________________________________ > Freetel-codec2 mailing list > [email protected] > <mailto:[email protected]> > https://lists.sourceforge.net/lists/listinfo/freetel-codec2 > <https://lists.sourceforge.net/lists/listinfo/freetel-codec2> > > > > > ------------------------------------------------------------------------------ > Check out the vibrant tech community on one of the world's most > engaging tech sites, SlashDot.org! http://sdm.link/slashdot > > > > _______________________________________________ > Freetel-codec2 mailing list > [email protected] > https://lists.sourceforge.net/lists/listinfo/freetel-codec2 > ------------------------------------------------------------------------------ Check out the vibrant tech community on one of the world's most engaging tech sites, SlashDot.org! http://sdm.link/slashdot _______________________________________________ Freetel-codec2 mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/freetel-codec2
