jks

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jks
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  • Find your Kiwi using my.kiwisdr.com

    Got a Kiwi (running v1.330+) on your local network with an unknown local IP address? Like a new Kiwi out-of-the-box? Now from a browser on the same local network you can connect to my.kiwisdr.com and be automatically redirected to the Kiwi. The local IP address of the Kiwi will then show in the browser address bar.

    This feature is similar to that provided by other IoT devices. It requires that the Kiwi have access to the Internet when it starts up. And that the computer running the browser is on the same local network as the Kiwi. If there are multiple Kiwis on the network the browser will display a table of Kiwis by serial number and a link that will connect to each one.

    Our documentation lists 5 different methods of determining a Kiwi's IP address. But each has its limitations and disadvantages. Now there is a sixth method that is particularly convenient.

    If you want to opt-out of your Kiwi sending this information to kiwisdr.com each time it starts then set the switch on the network tab of the admin page to NO: "Register this Kiwi on my.kiwisdr.com on each reboot?".

    This feature has not been tested with IPv6 or mixed IPv4/IPv6 local networks. So there is likely some debugging required.
    rz3dvpJimo
  • 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
  • Whistle or tone when not tuned exactly - version v1.397 [fixed in v1.398]

    Your IQ balance is almost certainly off as a result of pushing the "IQ bal" button in the IQ display extension when not tuned to a quiet part of the spectrum (or having the antenna disconnected). There is a topic explaining all this: http://forum.kiwisdr.com/discussion/699/why-a-beat-in-am-incorrect-iq-offset/p1

    Easiest way to confirm this is to check the beginning messages in the log tab on the admin page. You should see numbers for the I and Q balance that are either the default (-0.02) or roughly the same. Example:
    Thu Jun 18 15:46:49 00:00:32.361 ....      using DC_offsets: I -0.020000 Q -0.020000
    
    Powernumpty
  • 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
  • 30 min disconnection!?!?

    Time remaining (if any) appears in orange in the "users" tab of the main control panel as "h:mm:ss" counting down towards zero. The suffix is "act" if the limit is on activity per connection and "24h" if the limit is per 24-hour period. The time in white preceding is how long you've been connected and counts up.

    image
    mdfrc99WA2ZKD
  • 30 min disconnection!?!?

    Time remaining (if any) appears in orange in the "users" tab of the main control panel as "h:mm:ss" counting down towards zero. The suffix is "act" if the limit is on activity per connection and "24h" if the limit is per 24-hour period. The time in white preceding is how long you've been connected and counts up.

    image
    mdfrc99WA2ZKD
  • RSSI value doesn't match Spec plot

    The S-meter code is literally:
    s_meter_power = I*I + Q*Q
    s_meter_dBm = 10.0 * log10(s_meter_power / SND_MAX_VAL)
    s_meter_value = an_averaging_function(s_meter_dBm)
    
    Where I and Q are the two quadrature components (complex number) of the audio signal after passband filtering. So it contains all the data you see (and hear) within the yellow passband area on the waterfall, except that the actual data is coming from the audio path not the waterfall path. So it doesn't have anything to do with the spec plot. The spec plot is just the waterfall data plotted in a non-scrolling way (as a 2D graph).

    It's easy to forget because they both typically tune together. But the audio and waterfall are two entirely independent DDC (digital down conversion) receivers. You can re-tune the waterfall to go look at a completely different part of the spectrum without effecting the currently received audio. So a "4-channel" Kiwi is actually an 8-channel DDC SDR. This is why the unbalanced FPGA configurations are possible, i.e. rx8_wf2. The lack of waterfall on the other 6 audio channels is made up for by the audio FFT computed on the browser basically for free.
    bensondjacobs
  • RSSI value doesn't match Spec plot

    The S-meter code is literally:
    s_meter_power = I*I + Q*Q
    s_meter_dBm = 10.0 * log10(s_meter_power / SND_MAX_VAL)
    s_meter_value = an_averaging_function(s_meter_dBm)
    
    Where I and Q are the two quadrature components (complex number) of the audio signal after passband filtering. So it contains all the data you see (and hear) within the yellow passband area on the waterfall, except that the actual data is coming from the audio path not the waterfall path. So it doesn't have anything to do with the spec plot. The spec plot is just the waterfall data plotted in a non-scrolling way (as a 2D graph).

    It's easy to forget because they both typically tune together. But the audio and waterfall are two entirely independent DDC (digital down conversion) receivers. You can re-tune the waterfall to go look at a completely different part of the spectrum without effecting the currently received audio. So a "4-channel" Kiwi is actually an 8-channel DDC SDR. This is why the unbalanced FPGA configurations are possible, i.e. rx8_wf2. The lack of waterfall on the other 6 audio channels is made up for by the audio FFT computed on the browser basically for free.
    bensondjacobs