Last night represents what was probably the strongest session in several nights as the noise floor here in Texas has returned to quiet levels. It may not have been limited to here as Laurence, KL7L / WE2XPQ, reported my signal after more than a week of no reports. Similarly, Ken, K5DNL / WG2XXM, noted strong signal reports from VA7JX and WH2XCR. Mark, WA9ETW, reported my CW ID at RST 579 to 589 during the evening. The band was open.
The geomagnetic field was quiet and stable with a Bz that was slightly variable but North-pointing this morning and solar wind velocity remains low at 315 km/s.
Neil, W0YSE/7 / WG2XSV, experienced a strong session and offers the following comments:
Roelof, PA0RDT, reports VO1NA’s CW at audible levels during the session. Interestingly enough, keying sidebands are observed. That’s a strong signal!
John, VE7BDQ, sent a report for four-hours of WSPR that yielded 26 reporting stations in order of most distant: ZF1RC, WH2XCR, K4LY, WG2XJM, W5EST, WA9EIC, SWL/K9, WG2XIQ, WG2XXM, W0JW, WD0AKX, WB0VAK, KL7L, KB0BRY, NO1D, AC0ZL, N6SKM, WW6D, WI2XBQ, N7BYD, VE7KPB, WG2XSV, WH2XGP, VA7JX, VA7MM, and VE7CNF. John was also seven station, including WD2XSH/15, WG2XIQ, WG2XXM, WE2XPQ, WI2XBQ, WG2XSV and VE7CNF.
WSPR activity appeared to be very good although I only checked the activity figures once early in the evening where 70 MF WSPR stations were reported on the WSPRnet activity page.
Regional and continental WSPR breakdowns follow:
There were no reports from the trans-Atlantic or trans-African paths. EA8/DJ9XJ and UA0SNV were present during the session but reports were found in the WSPRnet database.
Eden, ZF1EJ, and Roger, ZF1RC, provided reports from the Caribbean. Roger had a nice “razor thin” path to the Pacific Northwest while Eden’s best DX was WG2XKA in Vermont.
In Alaska, Laurence, KL7L / WE2XPQ, receives reports from stations in the West and reports me, WG2XIQ, while receiving as KL7L.
In the Pacific, Merv, K9FD/KH6 / WH2XCR, reports an antenna problem, possibly related to a vacuum relay. He will be investigating today. As a result, Merv was mostly receive only during this session.
Phil, VK3ELV, received the following reports on the session:
Additional anecdotes, comments, statistics and information:
Larry, W7IUV / WH2XGP, reports that he decoded ten stations during this session.
Ken, K5DNL / WG2XXM, reports that he decoded seven and was decoded by 39.
Toby, VE7CNF, reported the CW ID of Joe, NU6O / WI2XBQ, who was running QRP at .5 watts ERP at RST 339.
Mark, WA9ETW, reported that in spite of QRN he had audible copy on VE3OT/B and WD2XSH/31/B.
Doug, K4LY / WH2XZO, reports that he has suffered wind damage from the most recent storm system. He has some antenna plans for Spring and Summer.
Jim, W5EST, provided the following entitled, “WORKPLAN FOR 4-QUADRANT DAYTIME PROPAGATION VERSUS SOLAR FLARES”
“The Feb. 23 blog outlined how a 4-quadrant diagram can be used to test propagation predictions. Today I prescribe a plan of work I’d do to make and test one propagation predictor for 630m daytime propagation. Please look it over and e-mail us if you see some flaw or improvement that can be made in the plan of work itself.
Let’s recognize at the outset that the first simple predictor candidate will probably test poorly. So the purpose for now instead is to get some experience gathering information, see what numbers we get, identify problems and learn from them, and improve the daytime prop predictor by adding other types of information to it in the future.
Plan of Work:
1) Tabulate dates and letter-number classifications of all C-class and M-class and X-class solar flares since 8/1/2015 (~200 days). Use GOES-15 satellite data on solar X-ray e-mission from
2) Tabulate dates of reported daytime 630m propagation days by combining information from the following sources:
–Find KB5NJD blog mention of at least one instance of daytime propagation at sky wave distance between at least 2 stations on the day previous to the blog date, starting 8/1/2015. Use search feature in upper right corner to search the blog on keyword “daytime”. Then doublecheck each blog article having the keyword “daytime”.
—600MRG: Check for any entries referring somehow to daytime propagation and add each date pertaining to an actual report of 630m daytime propagation starting 8/1/2015.
— Cherry-pick W5EST propagation notes for dates of daytime propagation assembled from the ON4KST reflector and/or any other credible source. Starting 8/1/2015.
–A better way would query the WSPR database, but I lack the access and my own effort level.
3) Start with this predictor:
IF FLARE(Date) >= C.5 THEN 630M DAYTIME PROP(Date)=TRUE.
I could also try FLARE(Date-1) >= C.5 some other time.
If I could get solar wind data, the predictor Boolean could be made more complicated as well. Other space weather data could also be useful at some point.
4) Put numerical entries into the 4-quadrant diagram by counting dates from steps 1 and 2.
P+(+) is nr. of true positive overlaps of dates C.5+ & 630m daytime event dates.
P-(+) is false negative 630m daytime prop date but not C.5+ flare that date.
P+(-) is false positive when C.5+ but no record 630m daytime prop.
P-(-): All other days in the period are true negatives.
5) Expect a tradeoff between false negatives and false positives. If C.5 is too low or too high,
adjust it to optimize C.5 flare threshold so that the number of false negatives is about
1/3 of false positives. The “1/3” is based on “setting the bar” in the Feb. 23 blog article.
6) Report in a future blog post the flare optimum threshold.
Report the Precision P+(+) / P+(-) for C.5 and also for the optimized flare threshold.
Report the False negative rate P-(+) / (Total Nr 630m daytime prop dates) likewise.”
Additions, corrections, clarifications, etc? Send me a message on the Contact page or directly to KB5NJD <at> gmail dot (com)!