jks

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jks
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326
  • v1.391,392,393,394: New noise blanker and filters

    From the CHANGE_LOG file:
    v1.392,393  May 28, 2020
        Noise blankers and filters:
            Added the Michael Wild noise blanker. Not a lot of operating experience with this yet.
                It seems not to work on some noise sources compared to the standard blanker.
                A good test source is 100 kHz Loran-C in AM mode using a UK Kiwi.
                Increase the gate time (standard blanker) or impulse samples (Wild blanker) to
                account for the longer Loran-C pulses compared to the usual impulse noise.
    
            Fixed wdsp filter: the control sliders had no effect previously!
                Now it works quite well. You have to adjust the gain carefully to prevent overload.
    
            Added test pulse gain and pulse width controls. And also whether the pulse is
                applied before or after the passband filtering. The Wild blanker seems only
                effective on post-filter pulses. Probably because the filter is turning the
                pre-filter step function pulses into nicer band-limited pulses.
    
    bensoncathalferrisHB9TMC
  • v1.391,392,393,394: New noise blanker and filters

    From the CHANGE_LOG file:
    v1.391  May 23, 2020
        User interface changes:
            SAL, SAU mode passband image will only show single sideband (just like LSB, USB).
            Ctrl/alt-click on mode button toggles modes backwards (most useful with SAM modes).
            Same works with keyboard shortcuts, e.g. ctrl/alt-A toggles SAM modes backwards.
        
        Noise blankers and filters:
            Reworked the audio tab user interface to support multiple blanker/filter algorithms.
            New algorithms planned but not yet available are greyed-out in the menus.
            From Warren Pratt's wdsp package added the variable-leak LMS algorithm.
        
        Merged Howard Su's RPi changes.
            Note: RPi is not officially supported by KiwiSDR. Ask for help on the KiwiSDR forum:
                http://forum.kiwisdr.com/discussion/1986/port-kiwisdr-to-raspberrypi-3b
        
        Bug fixes:
            Audio recordings made in SAS (synchronous AM stereo) mode now work.
            Fixed problem with ITU region 2 Kiwis and shift-clicking waterfall in 75/80m band segment.
            from lazywalker: fixed problems with frequency memory and reload value when transverter offset used.
    
    rz3dvpPowernumptyWA2ZKDChrisSmolinskiLX1DQhowardsuLonecrowHB9TMC
  • v1.391,392,393,394: New noise blanker and filters

    From the CHANGE_LOG file:
    v1.391  May 23, 2020
        User interface changes:
            SAL, SAU mode passband image will only show single sideband (just like LSB, USB).
            Ctrl/alt-click on mode button toggles modes backwards (most useful with SAM modes).
            Same works with keyboard shortcuts, e.g. ctrl/alt-A toggles SAM modes backwards.
        
        Noise blankers and filters:
            Reworked the audio tab user interface to support multiple blanker/filter algorithms.
            New algorithms planned but not yet available are greyed-out in the menus.
            From Warren Pratt's wdsp package added the variable-leak LMS algorithm.
        
        Merged Howard Su's RPi changes.
            Note: RPi is not officially supported by KiwiSDR. Ask for help on the KiwiSDR forum:
                http://forum.kiwisdr.com/discussion/1986/port-kiwisdr-to-raspberrypi-3b
        
        Bug fixes:
            Audio recordings made in SAS (synchronous AM stereo) mode now work.
            Fixed problem with ITU region 2 Kiwis and shift-clicking waterfall in 75/80m band segment.
            from lazywalker: fixed problems with frequency memory and reload value when transverter offset used.
    
    rz3dvpPowernumptyWA2ZKDChrisSmolinskiLX1DQhowardsuLonecrowHB9TMC
  • KiwiSDR production status and availability

    Aluminum enclosures: Mouser now has 40+ in stock.
    WA2TP
  • BeagleBone AI

    Below shows progress with an experiment to get a 14-channel configuration working using a BeagleBone AI. The challenge is to move as much processing to the second cpu core of the AI as possible so as not to impact the realtime requirements of serving the 14 audio channels (plus the usual 12-channel GPS etc.) It seems to work. A 14 audio DDC + 1 waterfall DDC configuration (rx14_wf1) was made to fit in the FPGA (LUTs now 97% full) by reducing the amount of CIC filtering logic slightly.

    Note below that the processor temperature and clock speed are displayed. The cores are currently running at rate automatically adjusted based on temperature between 1.0 - 1.5 GHz due to the reduced cooling configuration I'm testing.

    image

    The Kiwi's internal WSPR extension is running on all 14 channels as a worst-case test since WSPR decoding is so cpu intensive. The fact that this works does not change the fact that Rob's wsprdaemon is the superior solution for anything but casual WSPR monitoring. In fact 14 channels was chosen in support of getting a single Kiwi to work in an all-band wsprdaemon setup.

    Below is output from the Linux "ht" command. It shows how certain components of the software have been moved to new Linux processes separate from the main Kiwi process and "locked" to the second core of the processor. "kiwid" is the main process and is locked to cpu0 as seen in the "cpu" column. The other "kiwi.xxx" processes are locked to cpu1. Of interest here is the "kiwi.wsp" process which runs the collective WSPR decoding of all 14 channels.

    image

    This is just a progress report. There is a long list of work to do.
    PowernumptyChrisSmolinskiWA2ZKDHB9TMCKA7UG0LUJrz3dvpWA2TP