benson

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benson
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  • SuperSDR

    To try out SuperSDR, the installation instructions are at https://github.com/mcogoni/supersdr/

    KA7Urz3dvplinkz
  • v1.443: automatic SNR measurement, queue/camp panel reload button, misc fixes

    VK5QI created some good looking rrd plots as shown in his posts above. Also linkfanel's page with signal-to-noise ratio based scores is useful, but in order to visualize how these SNR values change over time and location I have been working on creating SNR plots in Python for single and multiple Kiwi stations. Now using jks recent addition of up to a week of hourly SNR data this has become a lot easier and quicker than previously where waterfall data had to be retrieved and processed for each Kiwi node.

    The multi station plots are for comparison of hourly data. Kiwi nodes have been selected for 4 longitude bands trying to get some reasonable geographic coverage and the list has been limited to 20 of the subjectively "better" stations.

    Please note that sometimes the SNR json files cannot be retrieved due internet connectivity time-outs and at times will possibly have missing hourly data points when all channels are in use. In addition the individual Kiwis can be offline for quite long periods as well.These plots are generated with 'bokeh', a versatile Python library for interactive visualizations that produces javascript for use in html web pages .

    The plots spanning a whole week do look crowded, but by clicking on the legends any or all bands can be turned off. On the top right corner you will find some tools including (wheel) zoom which make it easy to navigate the plots.

    Currently running as a trial on a RP3, you can check out the alpha version on http://sparks.epizy.com/SNR/MultiSNR_plots.html

    A pdf screenshot is attached.

    Note : on many browser F5 refreshes the browser cache.

    Powernumpty
  • Windows KiwiClient & Co

    Hi Paul,

    I am assuming that you have Python installed correctly and already unzipped the kiwiclient package.Depending on how far you got with trying to run kiwirecorder and using Python on your windows machine you can try the following steps.

    1. With explorer go to the directory where you unzipped the kiwiclient repository into.

    2. Check Python is properly installed by opening CMD and typing python or perhaps python3 in your installation. To exit python type in exit()

    3. For the remote kiwi(s) you want to use, have the ip adresses and port numbers ready. 

    4. As example here Shannon Volmet parallel transmission is used on 5505 and 8957 and a kiwi receiver in Finland. Provided the remote Kiwi has 2 slots available it will record both transmissions which then show up in your above mentioned kiwiclient directory. In the CMD window type:

    python kiwirecorder.py -k 30 -s kiwisdr.oh6ai.fi,kiwisdr.oh6ai.fi -p 8073,8073 -f 5505,8957 -m usb -L 200 -H 2700

    Stop the recording after a minute with the CTRL + C keys combination.

    5. Once you got this working, have a look at kiwirecorder.py --help to see what else you want to add, like limiting the recording time, add squelch parameters, append a station name or adding a directory where you want to save those wav files.

    Best regards, Ben


    WA2ZKDdl7awlPowernumpty
  • Ionosondes

    WA2ZKD wrote: seems like an extension for tracking one chirp TX could be possible (?)

    I recently used some auxiliary programs to tune KiwiSDR (via Catsync) and tracking certain chirp sounders to see if propagation is open in parts of the HF spectrum. Even without using Chirpview these programs allow synchronising the Kiwi with the sounder visually by trial and error and although not giving precise propagation delays and signal strength still give a good impression which part of the spectrum is open towards a particular sounder. A short video recording is attached*.

    Identifying those sounders remains a challenge like in the Chirpview days since the period & chirp time tables that can be found are all quite dated. I tried to use TDoA during stepper operation but usually only few usable points on the dt chart show up. The internet time delays probably wreak havoc not giving enough settling time for the remote Kiwis to be tuned to the stepped frequency. For the GPS locked sounders however the distance (path length) can be easily found using Chirpview.

    Likewise using the audio chirps or beeps to create an ionogram from the sweeps would require a known time delay. For the TDoA project this was already determined. Generating ionograms might be possible on the Kiwi internally but internet connections show unpredictable and continuously changing delays. Using a PPS signal I measured 1.4 to 2.2 sec delays between Kiwi rx in and audio out using a PPS signal on a local network. As mentioned in the forum ionograms are already available from the large GIRO network showing the more modern DPS4D pulse sounders.

    Three different programs were used that can step tune a receiver to follow chirp sounders. One (ref 1) tunes via a COM port output but is limited to 100 kHz/sec sweep rates and a 300 sec periods only.

    The others I found (ref 2) are more flexible however tune either via a localhost or DDE interface via HRD (Ham Radio Deluxe). Still trying to figure out how to bypass HRD altogether and send the data directly to Catsync via a virtual COM port.

    These steppers are not ideal and would need some modification in terms of interfacing, currently used sweep rates and sounder periods. Alternatively a frequency stepper could be built from scratch.

    So who knows at some point if there is sufficient interest and after enough of the remaining chirp sounders are identified this could lead to a Kiwi extension where a particular sounder is identified via a drop down list.


    ref 1 : https://www.qsl.net/pa1are/chirps.html
    ref 2: http://www.m0dts.co.uk/?tag=HF

    Best regards, Ben
    WA2ZKD
  • KYOTO News FAX 16969.1 kHz 23:00utc

    Over at Techzone ( https://goughlui.com/2019/01/13/radio-radiofax-hf-fax-reception-on-kiwisdr-with-kiwifax-py/ ) there is series of blog posts with a lot of current info about HF fax reception in general , active frequencies and slant corrections.

    The author indeed shows that Kyodo as last HF fax news agency still transmits faxes at 60 lpm. Also he confirmed that BMF Taiwan has stopped its HF service long time ago and a good candidate for replacement in the Asia/Pacific drop down list would be XSG Shanghai.

    He also made some mods to kiwifax.py in order to let it run continuously for DX station capture, suppress the log file and add some drift corrections for non GPS Kiwi nodes.

    Regards, Ben
    KA7U