• ARLP014 Propagation de K7RA

    From mark lewis@1:3634/12.73 to all on Fri Apr 7 11:35:08 2017

    SB PROP @ ARL $ARLP014
    ARLP014 Propagation de K7RA

    ZCZC AP14
    QST de W1AW
    Propagation Forecast Bulletin 14 ARLP014
    From Tad Cook, K7RA
    Seattle, WA April 7, 2017
    To all radio amateurs

    SB PROP ARL ARLP014
    ARLP014 Propagation de K7RA

    Sunspot numbers and solar flux made a strong comeback over the past week, March
    30 to April 5.

    Average daily solar flux was 96.5 (compared to 77.9 the previous seven days, and 71.2 over the week before that, March 16-22).

    Average daily sunspot number progressed from 3.4 to 29.7 to 65.9 over the same three weeks.

    The latest daily forecast for Planetary A index and solar flux from NOAA and USAF (updated daily at ftp://ftp.swpc.noaa.gov/pub/forecasts/45DF/ ) shows solar flux at 76 on April 7, 70 April 8-13, 75 on April 14, 78 on April 15-16, 85 on April 17-19, 72 on April 20-23, 88 on April 24-27, 85 on April 28-29, 105
    on April 30, then 100, 97, 92, 85, and 80 on May 1-5, 75 on May 6-7, 78 on May 8-9, 75 on May 10-11, 78 on May 12-13, 85 on May 14-16, and 92 on May 17-20.

    The same forecast, but for planetary A index, shows 8 on April 7-8, then 5, 8, and 10 April 9-11, 8 on April 12-13, 5 on April 14-16, then 20, 18 and 10 on April 17-19, 5 on April 20-22, then 55, 28, 20, 22, and 28 on April 23-27, then
    15, 10, 8, 7 and 6 on April 28 through May 2, 5 on May 3-13, 20, 18, and 10 on May 14-16, 5 from May 17-19, then 55 and 28 on May 20-21.

    The site http://bit.ly/2o5Ts6g shows a nice image from a few days back of sunspot AR2644 and 2645. Also check http://bit.ly/2nNpeCC .


    F.K. Janda, OK1HH sent us this geomagnetic activity forecast for the period April 7-May 2, 2017.

    "Geomagnetic field will be:
    Quiet on April 9-10, 14-16, 20, 30
    Mostly quiet on April 8, 11, 19, 21, 29, May 2
    Quiet to unsettled April 12-13, May 1
    Quiet to active on April 7, 22, 24-28
    Active to disturbed on April 17-18, 23

    "Amplifications of the solar wind from coronal holes are expected on April (7-8,) 11-13. (15,) 16-19, 24-27

    "Remark: - Parenthesis means lower probability of activity enhancement and/or lower reliability of prediction."


    Thanks to David Moore (long time contributor to this bulletin) for this, on fast magnetic reconnection:

    http://bit.ly/2nkGwe8


    Max White, a British ham, sent this:

    https://go.nasa.gov/2nqXBiy


    If you would like to make a comment or have a tip for our readers, email the author at k7ra@arrl.net.

    For more information concerning radio propagation, see the ARRL Technical Information Service web page at, http://arrl.org/propagation-of-rf-signals. For
    an explanation of numbers used in this bulletin, see http://arrl.org/the-sun-the-earth-the-ionosphere.

    An archive of past propagation bulletins is at http://arrl.org/w1aw-bulletins-archive-propagation. More good information and tutorials on propagation are at http://k9la.us/.

    Monthly propagation charts between four USA regions and twelve overseas locations are at http://arrl.org/propagation.

    Instructions for starting or ending email distribution of ARRL bulletins are at
    http://arrl.org/bulletins.

    Sunspot numbers for March 30 through April 5, 2017 were 33, 65, 79, 75, 97, 75,
    and 37, with a mean of 65.9. 10.7 cm flux was 85.9, 90.6, 101, 112, 107.9, 93.8, and 84.6, with a mean of 96.5. Estimated planetary A indices were 23, 28,
    16, 8, 4, 20, and 10, with a mean of 15.6. Estimated mid-latitude A indices were 18, 21, 15, 6, 4, 17, and 10, with a mean of 13.

    NNNN
    /EX

    )\/(ark

    Always Mount a Scratch Monkey
    Do you manage your own servers? If you are not running an IDS/IPS yer doin' it wrong...
    ... What will today's generation tell their kids they had to do without?
    ---
    * Origin: (1:3634/12.73)
  • From mark lewis@1:3634/12.73 to all on Fri Apr 6 16:52:12 2018

    SB PROP @ ARL $ARLP014
    ARLP014 Propagation de K7RA

    ZCZC AP14
    QST de W1AW
    Propagation Forecast Bulletin 14 ARLP014
    From Tad Cook, K7RA
    Seattle, WA April 6, 2018
    To all radio amateurs

    SB PROP ARL ARLP014
    ARLP014 Propagation de K7RA

    We only saw sunspots over two days of this past week, March 30 and 31 when the daily sunspot numbers were 11 and 12. There were no sunspots during the previous week, so the average daily sunspot
    number rose from 0 to 3.3.

    Average daily solar flux changed from 68.2 to 68.6.

    Geomagnetic indicators were quiet, with average daily planetary A index declining from 10.6 to 5, and average mid-latitude A index going from 8.9 to 4.

    The averages for solar flux and A index shown at the end of last week's bulletin were incorrect, and have been corrected above. Thanks to AA2F for discovering my error.

    Predicted solar flux is 67 on April 6 to 12, 68 on April 13 to 22, 69 on April 23 to May 6, 68 from May 7 to 19 and 69 on May 7.

    Predicted planetary A index is 8 on April 6, 5 on April 7 to 9, then on April 10, 15 on April 11 and 12, 18 on April 13 and 14, then 15, 10, 5 and 8 on April
    15 to 18, 15 on April 19 to 21, then 12 and 10 on April 22 and 23, then 5 on April 24 to May 6, then 10, 15 and 20 on May 7 to 9. 18 on May 10 and 11, then
    15, 10, 5 and 10 on May 12 to 15, then 15 on May 16 to 18 and 12 and 10 on May 19 and 20.



    F. K. Janda, OK1HH sent this geomagnetic activity forecast for the period April
    6 to May 1, 2018.

    Geomagnetic field will be:

    Quiet on April 8 and 9, 24 and 25, 27 to 29, May 1
    Mostly quiet on April 19, 26, 30
    Quiet to unsettled on April 7, 10, 16 to 18, 23
    Quiet to active on April 6, 11, 13, 15, 20 to 22
    Active to disturbed on April 12, 14

    Solar wind will intensify on April (6 to 8,) 10 to 18, 23 to 25, (27 to 30)

    Remark:
    - Parenthesis means lower probability of activity enhancement.



    Mark Bell, K3MSB of Airville, Pennsylvania reported on April 5:

    "I've been trying to work Australia for quite a while on 160M. During the current 160M season I've heard bits and pieces of calls from VK land, and occasionally a complete call, but nothing strong
    enough to work.

    Saturday morning March 31 I was on 160M around 1030Z. I saw Ron VK3IO spotted and tuned to his frequency and was astounded at his signal strength! He was at
    nice 559, almost armchair copy as the
    saying goes. I was even more stunned that he answered my first call and received a 579 from him at 1045Z, which is about 35 minutes before my sunrise.
    At 1101Z I had the pleasure of working Luke
    VK3HJ, who was not as strong as Ron but putting in a very nice signal. My receive antenna is a 200 foot RBOG (Reversible Beverage On Ground) oriented NW/SE and my transmit antenna is an INV-L.

    On Wednesday 4 April 160M was pretty dead around 1030Z so I started calling CQ.
    A few KHz above me, Jon AA1K was also calling CQ. Phil VK6GX spotted Jon at 1024Z and myself at 1033Z. Later I emailed Phil and he said while he heard us,
    we were both too weak for a QSO.

    Phil also stated that openings from VK6 to the East Coast 'have been few and far between in the last few years. Signals often don't make it across the Nullarbor Plain to VK6.' "

    Interesting article on the history of solar photography:

    https://cosmosmagazine.com/space/snapshots-of-the-sun-since-1845



    From Tamitha Skov:

    "Outside of the bright region this week being a lot quieter and weaker than we hoped, we have a remnant coronal hole sending small pockets of fast solar wind our way. This is good news for aurora
    photographers at high latitudes, but it also brings a little more zing to the ionosphere for amateur radio operators and emergency responders suffering with low solar flux right now.

    Radio propagation on Earth's day side will likely remain poor, but you might be
    surprised how a slight bit of activity can really perk up the radio bands at night and in the gray line. GPS users should also enjoy better than average GPS conditions on Earth's night side, even at low latitudes where night time is
    often troublesome for GPS.

    But don't expect these conditions to last for more than a few days. Next week we will be dealing with a more serious chance of reaching solar storm conditions, when a much bigger coronal hole rotates into the Earth-strike zone."

    https://youtu.be/q5hvAqXiVL4



    For more information concerning radio propagation, see the ARRL Technical Information Service at http://arrl.org/propagation-of-rf-signals. For an explanation of numbers used in this bulletin, see http://arrl.org/the-sun-the-earth-the-ionosphere.

    An archive of past propagation bulletins is at http://arrl.org/w1aw-bulletins-archive-propagation. More good information and tutorials on propagation are at http://k9la.us/.

    Monthly propagation charts between four USA regions and twelve overseas locations are at http://arrl.org/propagation.

    Instructions for starting or ending email distribution of ARRL bulletins are at
    http://arrl.org/bulletins.

    Sunspot numbers for March 29 through April 4, 2018 were 0, 11, 12, 0, 0, 0, and
    0, with a mean of 3.3. 10.7 cm flux was 69, 68.8, 69, 69, 68.4, 67.8, and 68.5, with a mean of 68.6. Estimated planetary A indices were 4, 5, 7, 5, 5, 4, and 5, with a mean of 5. Estimated mid-latitude A indices were 3, 4, 6, 4, 4, 3, and 4, with a mean of 4.

    NNNN
    /EX

    )\/(ark

    Always Mount a Scratch Monkey
    Do you manage your own servers? If you are not running an IDS/IPS yer doin' it wrong...
    ... Am I going to die, doctor? Trust me, it's the last thing you'll do.
    ---
    * Origin: (1:3634/12.73)