jks

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

    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]

    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?

    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]

    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
  • Offset issue [offset field of label edit panel, fixed input parsing bug]

    That's precisely what it's used for. Click on an existing NDB entry to see (but I guess I don't ship with any NDB entries defined by default anymore). Anyway, when you set an offset in a label you should see that the label vertical line points at the frequency + offset position, but a small triangle appears at the carrier position. That's so you can tell which carrier belongs to the NDB. The offset field can be set to a positive or negative value in case the NDB modulates on only one sideband (or is stronger on one sideband, or you need to place the label on the opposite sideband because there are too many labels already on the other sideband).

    Another NDB assist: the large (outer) + and - frequency step buttons will increment in alternating 400 and 1000 Hz steps to match the common NDB modulation spacings.

    WA2ZKD