FT8 is already encroaching on the PSK subbands (or in the case of 17 meters right on top of the PSK subband) and probably others too. PLEASE be a good neighbor and don't do anything to make it worse. Everyone needs to share a very limited resource. Just because FT8 is popular does not provide license to rain on everyone else's parade.
Mike WM4B On Mar 6, 2018 9:49 AM, Joe Taylor <j...@princeton.edu> wrote: > > Hi Phil, > > Your idea sounds reasonable. It might be a good way to enable wideband > receiving -- that is, reception (of FT8, say) over a passband > significantly greater than 5 kHz, currently the practical limit. The > popularity of FT8 on the HF bands implies that wider sub-bands would be > very desirable. > > With MAP65 we already have significant experience with wideband > reception of JT65 EME signals. It works very well, and is a big > advantage. It can be set up to decode all JT65 signals over a 90 kHz range. > > When receiving WSJT-X currently acquires audio data via the C++ class > defined in Detector.cpp. Your best contact person is probably Bill, > Somerville, G4WJS. Fair warning: Bill is in the middle of some major > contract work, so his available time is limited. > > -- 73, Joe, K1JT > > On 3/6/2018 1:29 AM, Phil Karn wrote: > > How hard would it be for WJST to accept receive audio from a RTP (Real > > Time Protocol) multicast network stream? > > > > RTP is *the* standard for voice over IP (VoIP). It runs over UDP/IP, > > usually as unicast IPv4 but also as multicast IPv4 or IPv6. It's just a > > streaming protocol that identifies and sequence numbers packets. It can > > carry any codec you want. > > > > I've been writing my own SDR from scratch over the past year or so. A > > core design feature is the use of IP multicasting for all inter-module > > communications, e.g., I/Q sample streams, uncompressed PCM audio, > > Opus-compressed audio, decoded digital data frames, hardware status, > > metadata, etc. > > > > I've found this to be remarkably versatile and practical. Any number of > > receivers can listen to a multicast stream without any prior > > arrangement. The various modules can be on the same system, on different > > systems on the same LAN, or systems in different locations connected by > > a multicast-capable IP network. Modules can be individually stopped and > > restarted without killing others (though some real-time data will of > > course be lost.) > > > > My receiver outputs uncompressed audio as a standard RTP/UDP/IP > > multicast stream containing mono or stereo 16-bit linear PCM audio at 48 > > kHz. To now get this into WSJT on OSX, I run my RTP receiver/player > > program, intercept the OS X audio with Soundflower, and then tell WSJT > > to take its input from Soundflower. > > > > This sort of works, but it causes problems. You have to be careful to > > keep system sounds out of Soundflower, and you can't run any unrelated > > sound applications. > > > > It would be great if WSJT could natively process an incoming RTP audio > > stream without touching the local machine's audio subsystem. It would > > not have to echo to the system audio output; if want to monitor it I can > > simply run an instance of my RTP audio player that will join the same > > multicast stream and WSJT doesn't need to know. > > > > As a follow-on project, it would also be nice to give WSJT the option of > > generating a RTP stream with transmit PCM audio. > > > > I'm willing to do the work myself, but I'd like to know if anybody else > > is already working on something like this, or if anyone has advice for > > how to minimize my changes to the WSJT program structure. (I've not > > looked at the source yet.) > > > > 73, Phil > > > > > > ------------------------------------------------------------------------------ > > > > Check out the vibrant tech community on one of the world's most > > engaging tech sites, Slashdot.org! http://sdm.link/slashdot > > _______________________________________________ > > wsjt-devel mailing list > > wsjt-devel@lists.sourceforge.net > > https://lists.sourceforge.net/lists/listinfo/wsjt-devel > > > > ------------------------------------------------------------------------------ > > Check out the vibrant tech community on one of the world's most > engaging tech sites, Slashdot.org! http://sdm.link/slashdot > _______________________________________________ > wsjt-devel mailing list > wsjt-devel@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/wsjt-devel ------------------------------------------------------------------------------ Check out the vibrant tech community on one of the world's most engaging tech sites, Slashdot.org! http://sdm.link/slashdot _______________________________________________ wsjt-devel mailing list wsjt-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/wsjt-devel
