jks

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jks
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  • Sound recording from multiple opened browse windows for diversity reception?

    jksjks
    @zfyoung,

    Your original post mentioned diversity reception, but also IQ mode. What exactly did you have in mind that was IQ-related? Were you thinking of traditional frequency diversity where kiwirecorder would open two connections on two different frequencies but merge the mono audio from each into a 2-channel file? (as L/R stereo) Or something more complicated?

    KA7U

  • Sound recording from multiple opened browse windows for diversity reception?

    jksjks
    Ron, when I was looking through the code I noticed he seemed to go to some trouble to keep the .wav header information updated as the file length grows. Probably so external readers of the file always see a consistent state as you noticed.

    KA7U

  • Map field problem [fixed]

    jksjks
    The values in the fields passed to Google maps are prepended with "http://google.com/maps/place/" When Google does the URL rewrite to use https the corruption of the location part of the URL seems to occur. If I specify https to begin with no URL rewrite occurs and the location part of the URL doesn't get changed. That will be the fix in the next update.

    rrobinet

  • Sound recording from multiple opened browse windows for diversity reception?

    jksjks
    On my Mac with "Python 2.7.3 -- EPD_free 7.3-2 (32-bit)" I was able to do this:

    python kiwirecorder.py -s kiwisdr.local -p 8073 -f 1521 -m am

    python kiwirecorder.py -s kiwisdr.local -p 8073 -f 1521 -m iq



    And generate these two files:

    20171118T225528Z_1000000_am.wav: RIFF (little-endian) data, WAVE audio, Microsoft PCM, 16 bit, mono 12001 Hz

    20171118T225615Z_1000000_iq.wav: RIFF (little-endian) data, WAVE audio, Microsoft PCM, 16 bit, stereo 12001 Hz


    They played back fine, but the iq file didn't sound quite right as you mentioned. It sounded like the I (or Q) channel was just being duplicated in both left/right channels. It was missing the "phase shifting" effect you normally hear between the stereo channels. I'll have a look at this.

    WA2ZKD

  • Who runs Linux for their main OS/Browser [how to run Dream on Linux]

    jksjks
    Under "Chart Selector" the "History > SNR / Audio" chart is a good way to see the SNR trend as propagation changes. It also charts audio drops over time.
    I find that +15 to +18 dB SNR minimum is needed for uninterrupted audio when the broadcaster is using 64 QAM.

    KA7U