Wednesday, September 7, 2011

The 2011 10-Meter Spring/Summer Es Season

The 2011 10-Meter Spring/Summer Es Season
By Art Jackson KA5DWI

Background:
The following documentation is a summary of the 2011 Spring/Summer Es season based upon PropNET captures and identified fragments received at the home QTH of Art Jackson, KA5DWI, maidenhead grid square EM12ju located near Fort Worth, Texas. All of the data analyzed and displayed in this summary was accumulated by the software PNP (formally known as PropNETPSK, written and maintained by Jeff Steinkamp, N7YG. All captures logged were of the mode PSK31 from other participants of PropNET (www.propnet.org) and others located near the 10-Meter operating frequency of 28.1188 MHz. No other frequency, bands or modes of communication were used in this synopsis. Data using PropNET captures of KA5DWI transmissions are used for comparison purposes only and captures of non-PropNET participants were used for probability measurements and non-Es propagation phenomena.

On occasion I will make references to past years in this summary. A 5-Year, followed by a 6-Year study of 10-Meter Es was written and published in 2010 and 2011 (Central States VHF Society Conference Proceedings). The data used in this analysis will be added to a 7-Year study in the future.

Any opinions and theories expressed in the summary are independent thoughts of my own and not to be construed from those members and officials of PropNET. My personal thanks go out to everyone involved and participated in PropNET for both the current and the past 8 years.

Operating:
QTH - North Richland Hills, Texas (Grid Square EM12ju), a northeastern suburb of Fort Worth, Texas in a 35+ year old neighborhood surrounded by trees and in a creek valley. A ridge of hills between 1/3 and 1/2 mile away and no lower than 60 feet higher than the tops of my antennas runs from northeast to east of the QTH.

Equipment :
Primary Rig – 20+ year old Yaesu FT-747GX, running 10 watts.
Secondary Rig – Radio Shack HTX-10 (not used for transmitting, called Lurker mode in PropNET)
Antennas:
Primary – 3-Element Yagi @ 30 feet.
Secondary – 102 inch Whip Ground Plane @ 10 feet for severe weather conditions.

Operating Schedule:
Transceiver Mode – Operated 24 hours a day for most the season.
Lurking Mode – Operated a few Sunday evenings and Monday mornings and while on vacation (7/07-7/13) or whenever severe weather was expected or occurring.

Data Statistics (April 20–August 28, 2011):
First identified partial or capture – 23:39 UTC on April 20, 2011 (KP3FT FK68qa)
Last identified partial or capture – 23:47 UTC on August 28, 2011 (KP3FT FK68qa)
Total Captures and identified partials (April 25 until August 14) – 9,453 PropNET Captures and Identified Partial/Fragments, plus 1,528 Non-PropNET Captures in which calls and grid square were identified.
Total KA5DWI Captured by other PropNET stations – 5,676 (Data not used in analysis)

The Year’s Challenges:
1. Computer – I continued to run PNP on a Windows XP Home P4 1.8-GHz 648-Meg RAM Dell Desktop. It did not run as well as it had in past years. The best I could determine was that running the newest version of PNP along with a memory and CPU hungry antivirus software were totally incompatible. On the third day of vacation, PNP failed to connect to LiveX, ran and read very poorly. I had a few short-lived power outages early in the season.

2. Software - I used PNP Version 4.5.2.0 for the season on the XP Desktop and at times the XP Pro 3 Gig Dell Desktop. After much pleasure with the 4.3.X.X version, the new version software was a disappointment. It may have been due to a CPU hog antivirus program, but at the same time changes in the settings of both the software, and what appeared to be quirkiness with LiveX added frustration to a disappointing year in Es conditions. I had to manually recalculate several days of the measured season due to several minor incidents. The changes made to the settings and operations for both the software and LixeX were to enhance the Robot operations of the software, and in my opinion adversely affected the collection of propagation data for my purposes. I had to audit this year’s data much more than I had in past ones.

3. Weather – The weather was rather violent to begin the spring. We had 3 hailstorms in April. Beginning in July, one of the longest and worst heat-waves that have happened in history began. The lack of wind caused very high low temperatures, but helped keep down static.

4. Antennas – One end of the off-centered reflector on my 3-Element Yagi bent down about 30 degrees, but did not seem to affect overall performance. It is time to finally repair it.

Normal Operation:
Transceive Mode - Yaesu FT-747GX @ 10 watts into 3-Element Yagi pointed 60-110 degrees (80 usual) azimuth.
Lurker Mode – Radio Shack HTX-10 into the 3-Element Yagi or the vertical in bad weather.

Results – 2011 Spring/Summer 10-Meter Es Season @ KA5DWI EM12ju

By the end of 2010, I had compiled the data into a 6-year study and prepared it for publication. This year I was able to present it at the Central States VHF Society Conference in Irving, Texas. With the increase in solar activity, I felt that a 7th year of participation would be interesting.

Daily Figures from the Beginning to End of the Es Season
A Year That Was a Paradox

Daily Captures:
The Spring/Summer Es season of 2010 was one of the most “on average” of the 6 years of the study. The capture trend-line for the season was amazingly “right on”. The trend line had a slight shift to the left, indicating an early active season. Solar activity continued to increase during the fall and winter of 2010-11. Solar flux had been near 130 prior to this year’s season and at the beginning was around 110. As in 2010, this year’s season began very strong very early. The season seemed to be off to an exciting beginning, but it was short-lived. The expected peak that is annually experienced on 5/09 was weaker than normal and this trend continued until the second week of June.

The deficit between this year and the average of the prior 6 was as much as 39% of normal. The peak of the trend occurred on 7/17. At this point, the season appeared to be the worst measured. Out of the blue, things picked up, the deficit declined and the season finished strong. The 2011 Spring/Summer season was only the second worst in the 7 years measured.

The first chart shows how the daily activity of 2011 compared to the prior 6 years of the Es study that I have compiled. The “Regression” line is a best fit for the 6 years of data. The “Poly (2011Total)” is the polynomial line of best fit for this year. Notice that from the start of the season afterwards that activity is well below the average levels experienced for past years and the regression line. Good or at least normal activity levels did not occur until mid-June. The best part of the season was actually from mid-July to early August and is strongly evident by the trend-line (black dashes) and peaked about 2 weeks after the summer solstice.

It was all about the strength of the openings this season. The number of active hours once again (3 years running) were better than average. What is most obvious in this analysis was that the beginning and ending of the season was much better than past years. The peak of the season was very close to past experiences.

In most other years, the first 2 weeks of the season are slow. But like last year, it started off fairly active. Most days of the season, active hours were especially good and about 3 hours better than average. This year, peak daily volumes failed to be above normal and lows (valleys) were quite common. The peaks in activity were generally one day events. There were very few multiple highly active days and is prime reason for the short-fall. July 17 was the turning point and the salvation of a bad season. The seasonal median (midpoint) for activity was on July 2, much later than other years. The seasonal median (midpoint) for active hours was on June 29, also later than other years.

Despite lower results in activity, there was at least one PNP capture each day from May 3 until August 19. This was consistent with other years measured. The active hour measurement clearly shows the late peak of the season. Although better than average years, there was only one excellent day in which there was at least 21 hours was active.


3 Day Averages:
The “3-Day Average” is an average of daily captures two days prior to the day measured and the day measured. It shows about 16 short-lived peak periods for activity and about 12 for active hours. The slow growth of the season is quite clear as well as the later peak. The most highly active period again was the 3rd and 4th week of July and not the Summer Solstice. There were never any extremely high activity periods, nor with high active hours.


6 Day Average:
The 6-Day average is the average number of captures 5 days prior to and including the day measured. It shows approximately 11 peak activity days during the season (consistent with past years). This also shows that the season was much more inactive, along with the later peak. The daily hour open hour rate did not peak as sharply as it had in past years, but remained higher throughout the entire season.



Weekly Statistics:
After 3 years of measurements, statistics show that the Spring/Summer Es season begins 8 weeks prior to the Solstice and ends 10 weeks after. This year, the charts look like reflections of last year’s. The first half of the season was slow, the second half improved, and the exact opposite of what occurred last year.




Hourly Calculations
Captures:

In 7 years of measuring, the following chart confirms each year that the most active period for Es occurs mid-mornings, followed by a less active second peak during the late afternoon approaching sunset. This year the second peak was less pronounced and twilight hour activity was non-existent.

This chart represents the actual number of captures for each hour of the day from April 25 to August 28. It is shown as a 3-hour average to centralize the activity to a specific hour. For example, the 6 AM (6) local hour is the average of 5, 6 and 7 AM. The dual-peaked diurnal (daytime) pattern matched what occurred from 2006 through 2010.

Also, the number of captures that occur each open hour during the season closely duplicates the results of the capture activity chart above. These trends occur year after year. The more likely an opening is to occur, the better the quality of the opening. This year’s decline in activity was obvious on this chart as well. The only hour that improved this year was 7 AM.

Non-PropNET Captures and Captures of This Station:
In the 4th Quarter of 2009, it was decided to change the operating frequency from 28.131 to 28.1188 MHz. Moving below .120 allowed us to capture some of the activity on that frequency. The routine setup by Dave Donnelly, KF6XA accepts user non-PropNET captures via LiveX, pulls QTH data from QRZ.com and shows them as NPN captures, as well as adds them to the database. The routine is very selective. “CQ Contest” and “CQ 10-10” does not work.

After a hot first season, this season’s total NPN activity was down as well, but impressive nonetheless. Only 2,200 captures were added. I captured 506 different calls (down 200+), 208 grid squares (only down 6) and 27 DXCC entities (way up!). I had 19 transatlantic Non-PropNET captures (also up).

I have added this data to Open Hour, Distance and Directional statistics. Total capture activity charts remain PropNET data only. The hourly data rates were not strongly affected (about ¾ hour).

Throughout the season, non-PropNET captures favored morning times. There was no discernable dual peak. Again, many felt that Es were evening phenomena. It was due to most Hams operating in the evening not the morning.

The following charts are the PropNET captures, non-PropNET captures, and PropNET captures of KA5DWI during the season. The dual peak-diurnal pattern is evident in these charts and is much sharper than past years. Captures of my station were also much lower this year by 30%.


Results by Distance
As in all prior years, a vast majority of all 10-Meter PropNET captures occur at this QTH between 1251 and 1750 kilometers (770-1070 miles). This area encompasses Florida, Georgia, the Carolinas, onward to Michigan and the Southwest U.S. Much of thee captures longer than 2250 kilometers are Non-PropNET, except for KP3FT, Jeff in Puerto Rico. We lost Hawaii and gained back Puerto Rico.

New this year was a significant increase in Trans-Equatorial propagation over 5000 kilometers. Solar flux is still not high enough to support F2, and it is my opinion that Es are still a part of this propagation. From a presentation given by James Kennedy K6MIO/KH6 this July at the Central States VHF Society Conference, he associates much of our long distance multi-hop DX events in the Summer or Winter to a combination of Es and F2 influences.

Distances by Hour of the Day:
As mentioned before, the vast majority of PropNET captures at this QTH occur near the 1251-1750 kilometer mark. The dual-peaked diurnal pattern is evident at these distances and was similar to past years. Captures between 751-1250 kilometers also peaked in the late morning hours. Both distance groups declined this year.

Short distances (<750 km) are indicative of intense Es. No local captures are included. Most of these captures are warnings of possible openings on 2 Meters and “short-skip” on 6 Meters. I did not experience a single 2 Meter Es event this season, although 250 miles to my north experienced several openings. The further distance charted (1751-2250 km) show the dual peak favoring morning periods this season. Both distance groups declined this year.

Once DX occurs past 1750 kilometers, it becomes apparent that it strongly favored late afternoon to evening peaks. I have classified trans-equatorial captures separately in the next chart as it deserves special attention. Due to the loss of a PNP station in Hawaii and a gain of one in Puerto Rico, these distances shifted in activity this season.

These are new charts this season. It is the Trans-Equatorial propagation experienced this season compared to last year. Notice the significant increase from 2010.

The second chart is in 2,500 kilometer increments of the “TE” propagation. The shorter distance may be more Es than F2, the farther distances are more F2 like. In order by distance; northern South America, southern South America, and last New Zealand-Australia.

Hourly Directional Trends:
A way to determine what directions are best by the time of day is to separate all captures into directional half-groups.

The next chart divides the captures easterly (0-179.9 degrees azimuth) and those westerly (180-359.9 degrees azimuth). Each group is broken into the hourly percent of the daily total. This method eliminates skewing due to the differences in volume by each directional group. As noted in this year’s chart, easterly directions are best as the sun rises. Westerly opportunities peak 1 hour after easterly ones. The westerly second peak occurs quicker. The decline is slower after sunset to the west.


As then sun rises, northern activity rises quickly. By Noon, southerly ones catch up and continued to rise and drop quickly after sunset. Northern paths strongly favored morning hours, southerly ones favored afternoon.

Outside Affects on Es

I never want to say that I have all the answer to Es, but I am always curious to find what might affect them. I have determined that meteors do strongly influence them, and I also have identified that solar events have an effect.

This year was interesting again. In 2010 activity dropped significantly when solar flux began to rise. This year it appeared to do the opposite. As solar activity was high at the beginning of the season, PNP activity was above normal. When solar activity decreased, activity was way below normal. It never approached normal, or better than until solar activity increased in the later stages of the season.


There were slight increases in the K and A-Indices during rises in solar flux. There were no major long term extremes.

It goes to show you that it is hard to pinpoint solar influences on Es propagation.

Daily Capture Maps of KA5DWI EM12ju

There were very few “big” days this year. There were few good ones. I captured 50 non-local PropNET stations this year, down 4 from last year. Here are maps of outstanding days and overall coverage.

August 4, 2011. Best day for PNP & NPN captures.

June 12, 2011. The second best day this season.

July 27, 2011. The third best day this season

2011 Spring/Summer Es Season 10-Meter Grid Squares Captured


Summary:
I looked forward to see how a rise in the solar cycle affected Es. Overall it was a below average year and if not for the latter half surge, it would have been the worst. It appeared that the increase in solar flux may have had a southerly influence and put a lid on east-west propagation. Did the rise in the solar cycle deter Es?? The worst season was at the solar cycle minimum!! There is still a mystery for someone to figure out. Good luck.

Announcement:
I have been doing this for 8 years, 7 years full-time. It has been a pleasure and a thrill doing this. I did it only for the benefit of the Ham Radio community and for personal curiosity. I have seen many come and go with PropNET and was always pleased and grateful that Ev, Dave and Jeff kept things in line to my needs through 3 versions of software.

In time, I realize that the focus will change. You either adapt with the change, or move on.

That time has come. It is time to move on. I leave with gratitude and appreciation for what all of you have done over the years. A sincere thank you will never be enough. I will still be around researching and investigating, I just do not know what, when or how. I’ll let you know when I figure that out.

A Heart Felt 73s,
Art Jackson
KA5DWI
2011 KA5DWI Capture List

Once again, Rich-WD4RBX, Bob-WB8ILI, Jesse-K4EPS, Jerry-K8VGL, and Robert-K4RKM top the list.


Thank you again one and all for participating in 10-Meter PropNET.
© 2011 Art Jackson - KA5DWI

Monday, August 8, 2011

Es Propagation at the Summer Solstice

Hi all,

Now that I have figured out how to make PowerPoint presentations into Video, I can share with all of you what Es do each day.

The 6-Year Study clearly shows that Es are seasonal and peak around the Summer Solstice. Yes, there are other influences such as; meteors and a severe storm. BUT, the main influence is the tidal affect of the Sun on the Es layer around the solstice. (See the CSVHFS presentation).

Please view the PowerPoint showing a PropNET Capture Map of the 13 days around the Summer Solstice for this season. The background is the National Weather Service U.S. Radar Mosaic. It is in date order from June 15 to June 27. The solstice (June 21) is the middle day.

Each day is displayed in UTC hour order by day.

So if you are UTC time challenged, here is what the times mean:

00 UTC - Sunset approaches the East Coast
02 UTC - Sunset in the middle of the U.S.
04 UTC - Sunset on the West Coast
05-10 UTC Late night and twilight in North America
11 UTC Sunrise on the East Coast
12 UTC Sunrise in the middle of the U.S.
14 UTC Sunrise on the West Coast
18 UTC Solar Noon in the middle of the U.S.
20 UTC Afternoon throughout the U.S.

Also, be aware that the Sun rises earlier and sets later in the north.

So notice on the PowerPoint:
1. Es are spread out throughout the U.S at 00 'til 02 UTC.
2. Once the sun has set Es do occur, but are very very spotty. Actually this is the best time for early morning Es during the season, Overall, it is very quiet.
3. Once the sun rises (12 UTC), Es begin a rapid increase.
4. Intensity peaks close to 18 or 19 UTC as noon covers the central part of the U.S..
5. They begin to spread out late into the afternoon, but are not as intense. They are still excellent.
6. The second peak is occurring around 23 UTC.

Also, notice the Trans-Equatorial. It is much better this season and is probably associated with the rise of Solar Flux (Cycle 24). More on that later.

Enjoy. I am having fun doing this while the sun is scorching my grass.

73s
Art KA5DWI



PS.. Click on the arrows to the lower right for full screen

Sunday, August 7, 2011

Central States VHF Society Presentation



This is a test run for uploading PowerPoint Presentations to Video.
Please do not expect perfection. Use pause and play to control the slides.
I will edit this a little and re-submit it at a later date. I may add audio.

I presented this to the Central States VHF Society Conference on July 29, 2011. A paper was also published in the Proceedings.

Enjoy. I love talking about Es and entertain your questions and comments.

73s
Art Jackson - KA5DWI

Saturday, May 21, 2011

What happens in the E layer when 2 Meter Es occur.

Hi all,

Today (5/21) when the world was suppose to end...
Europe had a 2 Meter E opening.
This is what the E layer was doing. ..
No F2 could be read because the Es layer was so well ionized.

Weather had nothing to do with it. 73's Art

Monday, April 4, 2011

What to Expect During the Spring/Summer Es Season

Here is a recap of what you can expect during this year's Spring/Summer Es Season.

Es appear around April 21th to the 25th now and then. The first full scale opening appears near May 9-11. By the end of May, Es are in full swing and will not decline until mid-August. Activity-wise, it peaks very near the Summer Solstice. It rises quickly and takes its time end.

This chart represents the daily active hours you can expect during the season. For about 6 weeks, beginning the third week of May you can expect as much as 12 hours of Es each day. Three days (6/13, 6/18 and 7/4) average 16 hours.

The next 4 charts show the probability of working 10-Meter Es each week of the season. The dates listed are the beginning of each week.



Monday, December 20, 2010

A 5-Year 10-Meter Es Propagation Study Using PropNET - Final Part

Questions and Answers:
“Is Es propagation truly a seasonal occurrence?”
The answer derived from this study is definitely yes. The season begins within days of April 25 and progressively increases up to May 6, at which time it is in full swing and remains totally active until at least August 15. There is still a good chance that activity continues till the end of August. From the study, the season begins 8 weeks prior to the Summer Solstice and ends around 10 weeks after it.

“Since it has been determined to be seasonal, is activity evenly distributed around the Summer Solstice?”
After three years, I thought it was not. But now after 5 years I believe it is. The best part of the Es season is concentrated in the first half (8 weeks long) in a 4-week segment and one should make as much effort as one can during that period. Es are great from the 3rd week through the 6th week (May 9 – June 5). It might calm down slightly for the next four weeks around the solstice, but it in no way does it mean that the season is over. It is still very active during that lull. Once we arrive at Independence Day (July 4th), the season picks up again and it is not until around August 1 that a real decline is noticed. The season does not actually end until sometimes between August 15 and September 1. Statistically and graphically it has a slight right-skewed distribution of opportunities, still the median points of captures and opportunities rested near the Summer Solstice.

“It appears that one works most of their QSOs during the afternoon and evening hours. Is this the best time to work Es?”
No it is not. It appears this way only because most Hams are active late in the afternoon and evenings. The absolute best hours are from after sunrise till the actual Solar Noon hour. On weekends and days off from work, make every effort during the season to work Es during these hours. The late afternoon hours are also very good, distances covered are also better, but opportunities decline once the sun has set. Es are mostly diurnal (daytime phenomena). Es do occur in the late evening and early morning hours. When they do, it is a very special event. Enjoy it and make use of the opening.

“Do Es favor specific directions at certain times?”
Yes it does, and it has to do with the location of the sun. It appears that you follow the sun in order to apply where it is best. As the sun rises, the best conditions tend to be towards the North and East. Gradually, as the sun is high over the horizon, southern paths improve. Once the sun has moved beyond Solar Noon, western paths become better than eastern ones. Therefore, the tendency is that openings appear in the east and north first and then will develop towards the south and the west later on. The process starts over again in the afternoon as was displayed in the dual peak diurnal. Once the sun is setting, northern and western paths will decline in activity at a slower rate while southerly and easterly ones may drop off quickly.

“Can one predict when it is the best time to work real DX locations on Es?”
Yes…..
1. If the DX location is primarily east of you… Concentrate your efforts towards the DX station as your Sun has risen and then once again as the Sun’s Grey Line approaches the eastern DX locale.
2. If the DX location is west of you …Concentrate your efforts towards the western DX station as their Sun rises and then once again as your Sun sets.
3. For Northern and Southern DX paths ….Concentrate your efforts along the suns Grey Line as it leaves or approaches both locations.
This approach appears to produce better results.

“Do severe weather systems and the Jet Stream have any affects on Es propagation?”
Predominately it is small to absolutely none.
A weather system may influence Es propagation between two specific points (experienced here a few times), but I found it difficult to correlate its influence over the entire creation of the phenomena. This study covered 560 days of the Spring and Summer season, over a 5-year period. Of the entire seasonal total, I could only determine that an extremely small percentage of PropNET captures had anything to do with weather systems. In these 5 years, 2 of them were drought years with very little jet stream wind flow and little electrically active weather to speak of. If weather was the primary influence, the hourly charts would have represented trends indicative to weather affects. They clearly failed to do so. For three of the four years of the study, the morning daylight period was clearly the best times for Es propagation. Severe weather is a late afternoon, early evening occurrence. Captures in all four years never displayed the highest activity in the afternoon. In addition, Es would have also occurred at high levels in many other times of the season with varying levels. The study does not show that as is shown by its clear absence of captures in early April.

“Are there any other possible external influences that might affect Es?”
Probably meteors increase the probability of Es.
These were the actual daily captures of record for the 5 years of the study.

This is the potential meteor shower rates per hour for each day during the Es season.
Source: DL5BAC’s The Meteor Scatter Predictor Program (TMSP)

It was not perfect for all peaks of meteor activity, but many of the spikes in captures during the 5 years coincide along them. Meteor influence was brought to my attention at the end of the season when there was an increase in Es activity on July 29-30, August 2 and August 13-14 when one would think that activity should have been very limited.

“What might cause the overall lull in activity and probability during the weeks around the Summer Solstice?”
The high angle of the Sun during this period might have an affect on Mid-Latitude Es. The Nighttime probabilities actually peak during the solstice, therefore it points towards the peak during this period. Maybe the heat radiated off the earth, in addition to the high sun angle deters ionization of the Es layer to some extent. The final two years were minimum solar activity years. The lull was much less pronounced during this time.

“Is the term “Sporadic” a proper identification of the Es propagation phenomena?”
Absolutely not.
The Houghton Mifflin Dictionary defines “Sporadic” as:
1. Occurring at irregular intervals; having no pattern or order in time.
2. Appearing singly or at widely scattered localities, as a plant or disease.
3. Isolated; unique: a sporadic example
The 5 years of the study and the resulting charts show that Es display no such conditions of being Sporadic.
Therefore, we should use the opposite term, “Periodic”.
“Periodic” is defined as:
1. Having or marked by repeated cycles.
2. Happening or appearing at regular intervals.
3. Recurring or reappearing from time to time; intermittent.
Periodic appears to be a much better adjective used to describe Spring/Summer Es propagation.

Future Plans:
I encourage that someone in a different location than mine participate in PropNET each Es season. Efforts to improve data collection from the database created by LiveX will make it much easier to produce statistical analysis for more than one PropNET participant and I will look into this investigation in future years as long as there are an adequate number of participants.

I would like to see the research expanded to 6 and 2-Meters. I am sure we would see similar results experienced between 10 and 6-Meters. PropNET 2-Meter activity would produce a much more worthwhile propagation database than what APRS could accomplish. High population of users and the FM mode in APRS mask many of the propagation conditions that occur on VHF. PropNET could be more valuable than CW beacons.

I plan to list on a website a “Daily Probability” of Es conditions. I hope to have someone (or myself) to write a script very soon for general Ham Radio use that displays in date and time, the probability in percentage of experiencing an Es QSO on 10 Meters along with favorable directional data.

Glossary:

Afternoon Active - Most occur in the afternoon daylight hours.

Morning Active – Most occur in the morning daylight hours.

Averaging Data – It was used to smooth out peaks and lulls between actual days and better concentrate data gathered for hourly statistics. Solar Indices are displayed in running averages. It did not change the actual totals if the data displayed was accumulated.

Coefficient of Determination (R squared)- Is a measure used in statistics that indicates how well a calculated regression trend line approximates the actual data points. The scale is measured from 0.0 to 1.00. 1 reflects a perfect correlation.

Diurnal - Webster’s Dictionary defines this term as:
Recurring every day, occurring in the daytime, or opening during the day and closing at night.

Dual Peaked Diurnal – Two peaks of activity occur in the daylight hours.

Es Propagation – The bending of radio waves in the ionosphere at frequencies from approximately 10 – 230 MHz (25-50 MHz most common) by what is known as the E-Layer of the ionosphere (50-80 miles). Due to its lack of its predictability, it is often referred to as “Sporadic Es”. It is also known as “Short-Skip” because it propagates at shorter distances than normal F2 layer propagation at high frequencies.

Median – American Heritage Dictionary defines this term as:
Relating to, located in, or extending towards the middle

Probability Analysis – Based on the premise that one event occurs for a given time period. In the study, a single capture in an hour would have the same value at 100.

Right Skewed – Statistics term used to describe charted data. If most of the data volume is located to the left of center, it is considered right-skewed.

Right Tailed - Statistics term used to describe charted data. If the chartered data declines at a slower rate and time than it first rises, it is considered right tailed.

SE-Prop – DOS and Windows program developed by Jim Roop - K9SE that displays probable E-Cloud location and MUF between two stations.

Summer Solstice – It is the day that the Sun is directly over the Tropic of Cancer (approximately 23.5° North latitude). It is the highest elevation that the Sun will appear in the Northern Hemisphere. It marks the Winter Solstice in the Southern Hemisphere. When the same condition occurs in the Southern Hemisphere over the Tropic of Capricorn (approximately 23.5° South latitude), it is the Summer Solstice for the southern hemisphere and the Winter Solstice for the northern hemisphere.

Solar Noon Hour – The actual time (hour measured) that the Sun is due south. During Central Daylight Time it occurs at 13:18 or 1:18 PM.

Digisonde – A device that measures the values of returned high frequency radio signals transmitted and received in order to determine ionospheric layer altitudes. The University of Massachusetts Lowell Millstone Hill Digisonde is best known.

W6ELProp – Windows computer program developed by Sheldon C. Shallon, W6EL used for predicting ionospheric (sky-wave) propagation between any two locations on the earth on frequencies between 3 and 30 MHz. Earlier DOS versions were known as MINIPROP and MINIPROP Plus.

A Never-Ending Thank You to the PropNET Organization……..

Top 50 PropNET
Rank-Call-Grid Square-Captures
1 WD4RBX EM84NN 8713
2 WB8ILI EN82OQ 5933
3 K4RKM EM85VF 5160
4 W4JKL EM84AK 5026
5 K8VGL EM69UT 4752
6 AD4RX EL88OD 4443
7 KD5LWU DM57RI 2857
8 N7YG DM42NF 2655
9 K4EPS EL86UW 1752
10 NZ9Z EN64BD 1716
11 N4LR EM73QN 1626
12 KC9MEG EN52TI 1358
13 N4PSN EM84KP 1245
14 KI4EIZ EM63KN 1072
15 KI0GU EN35HF 974
16 WN4AMO EL98CW 861
17 KF6XA DM13JO 827
18 N8QLT EN82HL 707
19 KC6QJO DM05KH 701
20 N0OBG EM48RO 659
21 KC0EFC EM28OX 649
22 W3GYK EM85VF 620
23 WN3C FM19QC 539
24 W2EV FN03XD 529
25 AB0TJ DN60CN 514
26 WB8SKP EM56WR 509
27 WB4U EM94QU 493
28 W3NRG DM12JQ 491
29 NI5F EM42UF 459
30 K5BTV EM74WG 376
31 KF9KV EN52ET 374
32 W6CGH DM13BR 347
33 WA0JYF EN42EB 333
34 WB8SKP EN66TD 326
35 WB4JFI EM92XU 314
36 KC0TLN EM28QX 306
37 WV5L DM65PG 275
38 AB9MS EN42XN 268
39 KD5CFB EM40IQ 221
40 AI4NV EL87PX 192
41 K1HOP FN31SS 191
42 W4DDR EM85BW 177
43 NM4V FM06NR 176
44 NH7O BL10WP 162
45 NK8Q FN20GN 153
46 N5XYO DM90QQ 145
47 WD4ELG FM06LA 139
48 N2JR FM18CO 137
49 K3OMG EN82EI 126
50 W7IXZ DN05XJ 122

73s Art Jackson KA5DWI

A 5-Year 10-Meter Es Propagation Study Using PropNet - Part 10

The Final Level of Analysis:
Now that 5 years of data was collected and PropNET participation each year was consistent and the data displayed definitive trends, there still existed a few unexplained holes. Although I averaged combinations of days and hours, most of these charts displayed many peaks and valleys. It stirred up my curiosity and I decided to investigate it on a micro level.

Five years of participation had produced good probability data supported by capture numbers. It was proven that the higher the probability of Es, the number of captures during the occurrence was also higher. With this mind, the volume and incident data was combined to the level of a specific day and specific hour within it. The first attempt using 3-hour averages was not satisfactory. It failed to show extremes. In this analysis extremes need to be tracked in order to show the abnormalities.

In this final analysis, the hourly incidents (probability statistics) from April 25 to August 15 are graded on a 0 to 5 scale. A “0” ranking meant no opening, a ranking of “5” meant an opening all five years. Next, the hourly capture rate for each hour it was open was ranked in a similar manner. The hourly rate was based on the number of annual openings for that hour, not for the 5 year period. For example, if at 15:00 on May 23rd captures were recorded for 3 out of 5 years and a total of 60 captures occurred, a rate of 20 was assigned and applied to a similar scale (0-5).

The final process was to apply a scale based on the overall merit given from both probability and capture rates. The end result identified those events that appear to be special year to year during the Es season.

The Activity Scales:

The first activity scale applied to each hour of each day is one of probability. The low end (violet) will indicate no activity in 5 years. The high end (burnt orange) indicates an opening all five years.

The second activity scale is for capture rate when an opening occurred. It is based on the hourly capture rate as a ratio of the hours open.

The “Overall Rating Scale” is based on the combination of both the probability and capture rate scale. If there was no activity found, the “No Activity” (violet) is assigned. If one opening in five years with 6 or less captures occurred it was assigned “Light” (blue).

When viewing and interpreting these scales whenever it is yellow, orange or burnt orange (good to extreme) are the best times to operate. You will find that this occurs for most of the daytime periods into the median of the Es season.

The “Probable PNP No.” is a representation of the probable number of PropNET participants captured during the event. It may have been less, and possibly more and based on normal PropNET operating procedures.

The Chart:

The first row is the date of the season and the number of days prior to or after the Summer Solstice. The second row is the overall rating for each hour. Each date is displayed from local daylight saving time 12:00AM midnight to 11:00 PM. The third row is the probability rating. The number displayed was the years that an opening occurred. The fourth and final row was the hourly capture rate for those years open.

The results were somewhat startling. There are active days with good to extreme conditions, preceded or followed by poor ones. As this data was compiled, I realized that several of the days that had “Excellent” and “Extreme” conditions were days that I had experienced excellent VHF openings in the past.

By using this method of assessment and additional ranking of the daily results, the best days of each season can be identified. The DX enthusiast can now concentrate on individual days that historically produce excellent results.

60 days (slightly more than half) within the Es season have been identified as to being historically active days. In this review, an attempt to specifically detail traits will be attempted.

Es Activity Calendar:
Now that five years of data was collected, I was able to distinguish those days during the season that displayed excellent conditions. I have identified and ranked the 20 best days of the season for the following criteria:
1. High Rates – When open, a high rate of captures occurred.
2. High Activity – For the 5 years measured, a high number capture rate occurred overall.
3. High Probability – For the 5 years measured, a high number of open hours occurred.
4. Top 20 - Based on the 3 prior measurements, these days were within the top 20 days in the season.
5. Top 60 - Based on the 3 prior measurements, these days were within the top 60 days in the season.

The Best 20 Days of the Season:

The following dates are ranked from the 1st to the 20th.
6/16, 6/30, 7/8, 6/4, 6/3, 7/29, 6/5, 5/22, 6/29, 6/19
6/28, 7/13, 7/7, 6/15, 5/28, 6/13, 7/12, 7/28, 6/12, 6/23

1st Quartile Spring/Summer Es Season (April 25 – May 22):
The scale charting begins at 7:00PM on April 24. It signifies 00:00 UTC April 25. As noted, Es activity is very light and in five years measured, openings occurred for the most part only in one single year. The first evidence of any “good” level of Es activity occurs on the afternoon of May 4. The May 3-5 range shows the elevated levels. The first excellent conditions (orange) occur on May 9 and 10. The openings on this date occurred for only 2 to 3 years but when it was, the capture rates were at extreme levels (burnt-orange).

Activity levels improve and do have some periods less active. With the exception of the May 9-11 spark, the best conditions are during daylight hours.

Es Activity Calendar: April 25 – May 22
May 2: High Rates
May 3: High Rates Top 60
May 5: High Rates
May 7: High Rates
May 8: High Rates
May 9: High Rates High Activity Top 60
May 10: High Rates Top 60
May 11: Top 60
May 15: Top 60
May 20: Top 60
May 22: High Activity Top 20


2nd Quartile Spring/Summer Es Season (May 23- June 21):
The scale charting begins at 00:00 Local Daylight Time (Central) May 23. Es activity during each daytime period is very good (Yellow) in the five years measured. A few excellent hourly openings (Orange) will occur during daylight hours for most days in the quartile. The first evidence of extreme conditions (Burnt-Orange) in Es activity occurs on the morning of June 4-5. Some lulls in activity occur during this period, but are short-lived. 8 of the 20 top activity days occur in this quartile.

The best day of each Spring/Summer Es season is June 16. For 5 five years this date is highly ranked in probability, high hourly capture rates when open, and general high activity overall. The period from June 3 to June 17 are the best times of the season and should be the focus of all DX’ing activities.

Es Activity Calendar: May 23 – June 21
May 24: Top 60
May 26: High Probability Top 60
May 27: Top 60
May 28: High Activity Top 20
May 29: Top 60
May 30: High Probability Top 60
May 31 High Probability Top 60
June 1: Top 60
June 2: High Probability Top 60
June 3: High Activity High Rates Top 20
June 4: High Activity High Rates Top 20
June 5: High Probability High Activity Top 20
June 6: Top 60
June 8: High Probability High Activity
June 9: High Activity High Rates Top 60
June 10: High Rates Top 60
June 12: High Probability Top 20
June 13: High Probability Top 20
June 14: Top 60
June 15: High Probability High Activity Top 20
June 16: High Probability High Activity High Rates Top 20
June 17: High Probability Top 60
June 18: Top 60
June 19: High Activity Top 60
June 21: High Probability Top 60


3rd Quartile Spring/Summer Es Season (June 22 – July 20):
The scale charting begins at 00:00 Local Daylight Time (Central) June 22. Es activity during each daytime period remains very good (Yellow) in the five years measured. Excellent hourly openings (Orange) will occur during daylight hours for about 3/4th of the days in the quartile. A few lulls do occur. Extreme conditions (Burnt-Orange) in Es activity occur midday on June 30. As in the prior quartile, 8 of the 20 top activity days occur also in this one. The second and thirds best activity days of each Spring/Summer Es season are June 30 and July 8.

Es Activity Calendar: June 22 – July 20
June 22: High Probability Top 60
June 23: High Activity Top 20
June 24: High Probability Top 60
June 25: High Probability Top 60
June 26: High Probability Top 60
June 27: Top 60
June 28: High Activity High Rates Top 20
June 29: High Activity High Rates Top 20
June 30: High Activity High Rates Top 20
July 1: High Rates Top 60
July 3: Top 60
July 4: High Probability
July 5: Top 60
July 6: Top 60
July 7: High Probability High Activity Top 20
July 8: High Probability High Activity Top 20
July 9: High Probability Top 60
July 12: High Probability High Rates Top 20
July 13: High Activity High Rates Top 20
July 14: Top 60
July 16: Top 60
July 17: Top 60
July 19: High Activity Top 60


4th Quartile Spring/Summer Es Season (July 21 – August 15):
The scale charting begins at 00:00 Local Daylight Time (Central) July 21. During this period, Es begin a general decline. Still, Es activity during the daytime remain very good (Yellow) well into August. Excellent hourly openings (Orange) occur on July 28 and 29. July 29 has had a history of being one of the top 10 days of the season. Daily lulls become more common place, but no clear end of the season appears until August 15. Extreme conditions (Burnt-Orange) in Es activity do not occur during this period, although excellent conditions will occur as late as August 12. Only 2 of the top 20 and 7 of the top 60 activity days occur in the 4th quartile. The Es season ends quietly within 2 weeks after August 15.

Es Activity Calendar: July 21 – August 15
July 25 Top 60
July 27 Top 60
July 28 High Activity High Rates Top 20
July 29 High Activity High Rates Top 20
August 2 Top 60
August 3 Top 60
August 12 Top 60


Probabilities 8/15 – 8/28:
Beginning 8/15, Es activity begins to decline rapidly. As noted, it is not unusual to experience very good conditions now and then for an hour or two.


Next: The Final Recap, Helpers, Summary, Glossary