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Virtual Thoughts for a Virtual World

Virtual Thoughts for a Virtual World

  1. SDR I/Q Data Waveform Filtering

    by , December 9th, 2014 at 08:08 PM (Virtual Thoughts for a Virtual World)
    Let's work on the realization that a software defined receiver utilizing sound card sampling presents its I/Q data as a waveform. Now let's say we process the waveform being sampled by the soundcard and passed to the SDR application.

    Unfiltered I/Q data being passed to the SDR application at ~S8 noise level:



    Enabling waveform processing of the I/Q data:

    ...
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  2. Space Weather and HF Radio Propagation - 6/19/2013

    by , June 19th, 2013 at 07:52 PM (Virtual Thoughts for a Virtual World)
    Apologies for the lack of solar weather updates, as I have been restructuring my RF receiver setup. Anyway, on to the report....

    The sunspot number is 120, with sunspot AR1775 harboring some potential for significant flaring in the M-class energy range. A coronal hole is present, with increased solar wind energy possibly arriving at Earth over the weekend into early next week. Meanwhile, the Kp index is currently showing quiet conditions.

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  3. Space Weather and HF Radio Propagation - 5/22/2013

    by , May 22nd, 2013 at 07:05 AM (Virtual Thoughts for a Virtual World)
    The sunspot number is slightly down to 119, and sunspot AR1748 is showing less potential for high energy flaring. The Kp index briefly increased overnight, but it is now back down to a relatively quiet level.

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    Upper HF bands are showing sparse DX activity this morning, at least for North America. The 20m band is looking like the current best bet, with propagation into both Europe and Australia.
  4. Space Weather and HF Radio Propagation - 5/21/2013

    by , May 21st, 2013 at 08:28 PM (Virtual Thoughts for a Virtual World)
    The sunspot number is holding at 113, and sunspot AR1748 still holds potential for additional flaring. Otherwise, the Kp index is still relatively quiet, and might possibly remain so until increased solar wind from a coronal hole arrives around Thursday.

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    The 10m band is once again producing moderate DX conditions this evening, though as usual for this time of year, the 20m and 40m band are the better bet as the greyline ...
  5. Space Weather and HF Radio Propagation - 5/20/2013

    by , May 20th, 2013 at 08:20 PM (Virtual Thoughts for a Virtual World)
    The sunspot number is 113, with sunspot AR1748 holding potential for significant flaring. Additional solar energy is also streaming from a coronal hole and should impact Earth towards later this week. There has been a R1-class radio blackout in the past 24 hours, though the Kp index has since subsided down to a generally quiet level.

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    Upper HF and lower VHF enthusiasts could find moderate DX conditions on the 10m and ...
  6. Space Weather and HF Radio Propagation - 5/3/2013

    by , May 3rd, 2013 at 11:22 AM (Virtual Thoughts for a Virtual World)
    The sunspot number is down to 102, with sunspot AR1731 still holding potential for a significant flare event. Otherwise, the Kp index is currently quiet.

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    With a low noise floor, today could be a good day for HF DX enthusiasts. Even the 6m band is producing some contacts, both within North America and across the pond into Europe. 10m enthusiasts might also find TEP conditions into South America. 15m and 20m are open for ...
  7. Space Weather and HF Radio Propagation - 5/1/2013

    by , May 1st, 2013 at 10:20 PM (Virtual Thoughts for a Virtual World)
    The sunspot count is up to 165, with AR1730 and AR1731 still holding potential for significant flaring. The KP index is slightly up as well, peaking at 4 in the past 24 hours and now settling back down to 3. The Kp index could rise again when the previously mentioned increased solar wind from a coronal hole likely arrives at Earth towards weekend.

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    An increased HF noise floor should be expected tonight, at least until ...
  8. Space Weather and HF Radio Propagation - 4/30/2013

    by , April 30th, 2013 at 11:50 AM (Virtual Thoughts for a Virtual World)
    The sunspot number is up to 136, with sunspots AR1730 and AR1731 holding potential for significant flaring. Increased solar wind from a coronal hole should arrive at Earth later this week. As for now, the Kp index is relatively quiet.

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    10m band enthusiasts, especially long the east coast, might find a TEP opening into South America today. Otherwise, the 15m and 20m bands should be open for business into Europe.
  9. Space Weather and HF Radio Propagation - 4/26/2013

    by , April 26th, 2013 at 12:26 PM (Virtual Thoughts for a Virtual World)
    The Kp index is currently at 5 as increased solar energy is buffeting Earth's magnetosphere, sparking minor geomagnetic storming. The energy is arriving via the coronal hole mentioned earlier this week.

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    The sunspot number is 93, and sunspot AR1726 is still holding potential for powerful flares, though it is starting to move away from the Earth-side of the sun.

    Given the Kp index and geomagnetic flux, 20m ...
  10. Space Weather Update: Sunspot AR1726

    by , April 22nd, 2013 at 03:54 PM (Virtual Thoughts for a Virtual World)
    Sunspot AR1726 is now showing a delta class magnetic field, meaning an increasing chance of a significant flare event. The percentages are weighted more towards a M-class flare at 40% odds, though there is an estimated 15% chance of a more powerful X-class flare. Either way, given the location of AR1726, any produced flares are likely to track towards Earth. Sunspot AR1726 is the oval-shaped formation appearing in the upper-right quadrant of the following images.

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