[South Florida DX Association] ARLP003 Propagation de K7RA

[Bill Marx]

ZCZC AP03
> QST de W1AW  
> Propagation Forecast Bulletin 3  ARLP003
> From Tad Cook, K7RA
> Seattle, WA  January 20, 2006
> To all radio amateurs 
> 
> SB PROP ARL ARLP003
> ARLP003 Propagation de K7RA
> 
> As we cruise into the low part of solar cycle 23, the sun has been
> very quiet, save for some coronal holes providing solar wind
> streams. This week average daily sunspot numbers were up nearly ten
> points compared to last. The geomagnetic field has been mostly
> quiet, although a little more active than the previous week.
> 
> Over the next week expect solar flux to stay around 90, with
> geomagnetic conditions quiet, except for some unsettled to active
> conditions around January 23-24. Geophysical Institute Prague
> expects quiet conditions January 21, quiet to unsettled January 20
> and 22, unsettled January 25 and 26, unsettled to active January 23,
> and active conditions (higher A and K index) on January 24.
> 
> Rich DiDonna, NN3W of Virginia writes that, "While conditions on the
> high bands may stink, conditions on the low bands have been
> spectacular. 40 meters is opening to Europe as early as 2100z from
> the East Coast with reliable openings to the Middle East, and long
> path to Southeast Asia. 80 and 160 have also been amazing. So, while
> Old Sol may be in "nap" phase, one should not assume that there is a
> lack of DX to work!"
> 
> Jon Jones, N0JK of Kansas echoes Rich's comments about the lower
> frequencies in a January 14 email. He writes, "160 meter propagation
> to Europe from the Midwest and western USA is picking up. For a low
> band propagation beacon I listen to the 1.2 megawatt AM station from
> Kvitsoy, Norway on 1314 kHz. Its signal has been very strong the
> last couple of evenings. Great 160M conditions were noted by W8CAR
> and others the same time to Europe."
> 
> Jon also noted an extensive 6 meter E layer opening on January 13-14
> in which W1, W2, W3 and W4 stations were coming in.
> 
> Charles Lewis, S9SS of Sao Tome and Principe (an African island in
> the Atlantic Ocean about 150 miles west of Libreville, Gabon) was
> one of the stations reported in a recent bulletin by K7HP in Arizona
> as worked on 10 meters. Charles writes, "The reason Hank worked me
> that night is that I also use propagation beacons. On 10 meters, I
> primarily depend on the W3VD beacon in Laurel, MD. That evening, as
> I often do, I had the receiver tuned to the W3VD beacon while I
> worked at the computer across the room. About 2110z I heard the
> beacon rise dramatically out of the noise. I checked and found the
> band was becoming live with 10 meters stations. I fired up my amp
> and called CQ. In a period of about 40 minutes I worked about 40
> stations. I would have worked many more, but it took a while of rag
> chewing before I was discovered by the crowd."
> 
> He continues, "These late 10 meters openings are not very unusual
> for me in the 2015 to 2130z time frame. They more often start around
> 2030 to 2040z. They might last a few minutes or they might last a
> couple of hours. Until early last year, they were nearly nightly.
> Now they are a lot more scarce. There have been many times that I
> heard W3VD with a good signal and could raise no one or perhaps had
> a long rag chew with someone followed by no takers afterward."
> 
> Charles goes on to say, "I also had a very good opening on 12/11,
> the second day of the ARRL 10 Meters Contest that began about 2010z.
> I worked about 115 contacts coast to coast in NA over a period of
> about 50 minutes until it died. In that case also, I was working at
> the computer and heard W3VD pop out of the noise. The band usually
> dies about as suddenly as it comes to life."
> 
> He continues, "I am only about 20 miles north of the Equator. There
> is only about a 20 minute variation in sunset time over the year.
> The sun is usually down well before 1800z, so these openings are
> long after my sunset".
> 
> Charles says that on 20 through 12 meters he uses the IARU beacon
> system, and on 12 meters he often hears 4U1UN in NYC coming in
> strong, while no one else seems to be on the band. He says 20 meters
> is his best band for working the USA, and is the best way to
> communicate with friends near his vacation home in Western North
> Carolina.
> 
> Charles has an interesting challenge operating from his QTH, and
> that is from a huge Voice of America transmitter site that seems to
> hover over his station in a photo he sent. Check out a similar image
> on the web at, http://groups.msn.com/s9ss.
> 
> A couple of weeks ago Carl Luetzelschwab, K9LA had some comments
> about SSNe, or Effective Sunspot Numbers, and the T-Index. He
> continues with more comments below, through the end of this
> bulletin.
> 
> Carl begins, "In the January 6 Bulletin, I said the T Index and SSNe
> were similar methods that give a better picture of what the
> ionosphere is doing "now." Both represent an effective sunspot
> number based on real-time sounding of the F2 region critical
> frequency. Let's look at the basic difference between SSNe and the T
> Index.
> 
> "SSNe is calculated from a worldwide set of ionosondes at
> geomagnetic latitudes lower than 50 degrees. The SSNe plot also
> shows the RMS % difference between the foF2 values used to derive
> SSNe and foF2 calculated from the model using that SSNe as input.
> This parameter typically runs about 20% or so - if it exceeds 30%
> this indicates that the global ionosphere is departing more from the
> model expectation than usual. And if it exceeds 50%, buyer beware!
> 
> "The T Index is calculated from 14 ionosondes in the Australian
> sector. The regional maps (Australasia, Europe, and North America)
> show the difference between the predicted monthly T Index (which is
> in tabular format at www.ips.gov.au/HF_Systems/6/4/1) and the
> current observed hourly conditions in the desired region.
> 
> "Which one is best to use? That's a tough call, but I'd personally
> give the edge to SSNe for global predictions as it is based on
> worldwide data.
> 
> "To reiterate from the January 6 Bulletin, neither gives us a daily
> model of the ionosphere. But both do allow you to assess whether the
> current conditions are generally equal to, better than, or worse
> than the median value from your propagation prediction program when
> using the heavily averaged smoothed sunspot number (or smoothed
> solar flux).
> 
> "Thanks to Jim Secan of Northwest Research Associates in Tucson for
> information on SSNe and for forwarding the T Index information from
> Garth Patterson at IPS."
> 
> If you would like to make a comment or have a tip for our readers,
> email the author at, k7ra at arrl.net.
> 
> For more information concerning radio propagation and an explanation
> of the numbers used in this bulletin see the ARRL Technical
> Information Service propagation page at,
> http://www.arrl.org/tis/info/propagation.html. An archive of past
> propagation bulletins is found at, http://www.arrl.org/w1aw/prop/.
> 
> Sunspot numbers for January 12 through 18 were 12, 0, 0, 32, 42, 36
> and 50 with a mean of 24.6. 10.7 cm flux was 76.5, 76.5, 77.4, 80.9,
> 83.8, 82.5, and 85.6, with a mean of 80.5. Estimated planetary A
> indices were 3, 2, 3, 4, 14, 8 and 5 with a mean of 5.6. Estimated
> mid-latitude A indices were 2, 4, 2, 4, 8, 10 and 9, with a mean of
> 5.6.
> NNNN
> /EX
> 
> 
>