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jks

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jks
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  • DANGER: DO NOT do a manual Debian/Linux upgrade to your Kiwi! (update: but it's okay now)

    So it appears the Debian project and Beaglebone.org have stopped making updates to the Debian 8 (Jessie) release. For the Beagle, Debian 8.11 seems to be the last release. It has been run by a number of customers for a long time and also by us. So it seems safe now for Kiwi owners generally to do an upgrade and get the benefit of whatever security patches there have been between 8.5 and 8.11.

    To do this login as root using ssh/PuTTY and use the following commands. (this can not be done from the Kiwi admin console tab)
    If you haven't logged in this way in a while remember that your Debian root password has likely been changed to either the Kiwi admin password or the Kiwi's serial number if no Kiwi admin password has been set. The Debian root password has not been touched if you had set it to something other than the default of having no password.
    See this post for details: http://forum.kiwisdr.com/discussion/1801/v1-354-security-improvements-debian-root-password-no-longer-unset-blank
    cdp
    mst      (stops the Kiwi server)
    cd
    pkup     (shell alias for "apt-get -y install debian-archive-keyring; apt-get update")
    pkug     (shell alias for "apt-get -y dist-upgrade")
    
    (lots of output, takes roughly 10 minutes)
    
    reboot
    
    A few minutes after the reboot the Kiwi server should be responding again. If you login to the Beagle and type the "dog" command you should see:
    Debian 8.11
    BeagleBoard.org Debian Image 2016-05-13
    Linux kiwisdr 4.4.9-ti-r25 #1 SMP Thu May 5 23:08:13 UTC 2016 armv7l GNU/Linux
    
    There is still the open question of how the Kiwi distribution, and thousands of Kiwi customers, will migrate to the current Debian 9 (Stretch) and/or Debian 10 (Buster) releases which are available for the Beagle. This needs time for research as there are many issues involved.
    Powernumptyrz3dvpjapmedia
  • DPRK DRM testing

    The DRM mistuning detection is extremely good. Screenshot below is Radio Marti, received in PA, mistuned by +1 kHz (!) It locks and decodes fine. It also probably helps that they are running a very conservative configuration.

    The DRM spec has a little more information about the frequency pilot cells, section 8.4.2, page 121, http://kiwisdr.com/files/DRM/DRM.spec.v4.1.2.pdf

    image
    ka9q
  • Get a URL to the KiwiSDR with the current frequency, mode, and zoom?

    "/?ext=drm" since DRM is both a mode and an extension. Use e.g. "drm,3965" to select one of the preset frequencies.

    I can't remember why DRM can't be used as a mode selection in the URL. Some problem that was too difficult to fix no doubt.
    ChrisSmolinski
  • first fan died... how long do these things last- what other cooling alternatives ?

    When the aluminum enclosure was being developed I specifically asked Seeed to use a ball bearing fan (i.e. sleeveless). But I'm pretty sure now they didn't given the observed failure rates. I should ask again. Note that we receive no royalty on enclosure sales in an effort to keep the cost low. It's all Seeed's deal.

    Alternative fans and ideas are mentioned in these posts:
    http://forum.kiwisdr.com/discussion/comment/8667#Comment_8667
    http://forum.kiwisdr.com/discussion/comment/7102
    k5mo
  • QRSS and the Kiwi

    A simplistic but useful way of thinking about this issue is this: Suppose the waterfall is slowed to draw one line every ten minutes. During those ten minutes it could be sampling at ~21 Hz (full rate) and integrating those samples so the coherent QRSS signal is gaining a huge SNR advantage over the random noise. But the waterfall doesn't do that currently. It would just sit idle for ten minutes then take one sample.

    The integrate extension does a little better. It does integrate every time its waterfall output wraps around top-to-bottom. If the integration period (time to draw everything top-to-bottom) is short (e.g. 1 sec for time stations) then this is useful. But it isn't designed to work any better with long periods. So it's no good for QRSS signals.

    On the wish-list for a long time is a high-resolution FFT extension. One that could for example be used to resolve the millihertz differences of AM BCB stations (a technique already used very effectively by AM BCB DX'ers). Such an extension would naturally do long-period averaging in addition to high frequency resolution.
    k5mo