Hello Dani, all, last night I did the easy part: generating the JT9-2 (JT9-1 at half speed) audio. Next part of the project is to capture the incoming soundcard audio and store it as a WAV file at double speed, so the WSJT_X will "see" it as a regular JT9-1 signal. I have done similar thing before so that shouldn't be too hard either. For a first test I will just manually open the WAV file in WSJT-X. But that is not convenient at all, so I would like to automate that in some way or even better integrate the decoding into my own application.
In the BIN directory I found the file JT9.exe that in early versions of the users guide was documented as "Executable for JT9 and JT65 decoder". I wonder if that can be used (but maybe I should start that as a different thread). 73, Rik ON7YD - OR7T ________________________________________ Van: Dani EA4GPZ <[email protected]> Verzonden: dinsdag 11 september 2018 18:38 Aan: [email protected] Onderwerp: Re: [wsjt-devel] JT9-2 mode? El 11/09/18 a las 12:04, Rik Strobbe escribió: > Hello Joe, all, > > I understand that there are better ways to achieve a lower S/N decoding than > going back to JT9-2. > But awaiting this I would anyway want to do some tests with longer JT9 > transmission on 630m. > Since I am afraid that it is out of my league to dive in to the WSJT-X code > and modify it I thought of an alternative route: > Generate a "normal" JT9 signal, but transmit it at half speed. This > transmission will take 98 seconds and be at half the original audio frequency > (also half bandwidth). > At the RX side the audio is recorded as a WAV file, speed is doubled again > (just by changing the sample rate in the WAV file header) and this file is > fed to WSJT-X. > I know it sounds is a a bit of an odd thing to do, but at least feasible for > me. > Would this work (and improve SNR), or am I just trying to be too smart? Hi Rik, That would work. I have thought of the same idea sometime in the past, but never got to test it. 73, Dani EA4GPZ. _______________________________________________ wsjt-devel mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/wsjt-devel _______________________________________________ wsjt-devel mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/wsjt-devel
