Wednesday 22 September 2021

Hunting For NDBs In CLE272


ML - 392 Charlevoix, Quebec

It's CLE time! 'CLE's are 'Co-ordinated  Listening Events, and NDB DXers around the world focus their listening time on one small slice of  the NDB spectrum.

It's another normal one again with a 15kHz window -- the hunting ground is 385.0 - 399.9kHz.

A 'challenge target' for listeners in North America is ML - 392kHz in Charlevoix, Quebec. Listen for ML's upper sideband on 392.404kHz. ML is widely heard in Europe and throughout North America. Its 500W and big tower work well!

When tuning for NDBs, put your receiver in the CW mode and listen for the NDB's CW identifier, repeated every few seconds. Listen for U.S. NDB identifiers approximately 1 kHz higher or lower than the published transmitted frequency since these beacons are modulated with a 1020 Hz tone approximately.

For example, 'AA' near Fargo, ND, transmitted on 365 kHz and its upper sideband CW identifier was tuned at 366.025 kHz while its lower sideband CW ident could be tuned at 363.946 kHz. Its USB tone was actually 1025 Hz while its LSB tone was 1054 Hz.

Often, one sideband will be much stronger than the other so if you don't hear the first one, try listening on the other sideband.

Canadian NDBs normally have an USB tone only, usually very close to 400 Hz. They also have a long dash (keydown) following the CW identifier.

All NDBs heard in North America will be listed in the RNA database (updated daily) while those heard in Europe may be found in the REU database. Beacons heard outside of these regions will be found in the RWW database. These databases have recently been re-vamped and are slicker than ever before!

From CLE organizers comes the following CLE info:


Hello all,

 Have you tried one of our Co-ordinated Listening Events yet? 

Whether short logs or long ones, making them is enjoyed by beginners and experts alike - and reading them is enjoyed by all.

 Our 272nd Coordinated Listening Event starts this Friday.  This 15 kHz frequency range is quite a busy one, even the Pacific region (Oceania) having several NDBs to be found.


     Days:    Friday 24 Sept. - Monday 27 Sept. 2021

     Times:   Start and end at midday your LOCAL time

     Range:   385 - 399.9 kHz


Please log all the NDBs that you can identify with nominal (listed) frequencies in the range - it includes 385 kHz, but not 400 kHz - plus any UNIDs that you come across there.

 Send your final log to the List (not in an attachment, please) with 'CLE272’ and ‘FINAL' in its title (important).

 Show on each line:

    #   The Date (e.g.  '2021-09-24', etc.,  or just '24' )

    #   The Time in UTC (the day changes at 00:00 UTC).

    #   kHz  - the nominal published frequency, if known.

    #   The Call Ident.


Please show those main items FIRST.  Other optional details such as Location and Distance go LATER in the same line.

As always, of course, tell us your own location and give brief details of the equipment that you were using during the Event.


We will send the usual 'Any More Logs?' email at about 19:00 UTC on Tuesday so you can check that your log has been found OK.

Do make sure that your log has arrived on the List by 08:00 UTC on Wednesday 29 Sept. at the very latest.

We hope to complete making the combined results within a day or two.

You can find full details about current and past CLEs from the CLE page    It includes access to the CLE272 seeklists for your part of the World, prepared from all the previous loggings in Rxx.


Good listening

- enjoy the CLE.

     Brian and Joachim


From:      Brian Keyte G3SIA      ndbcle'at'

Location:  Surrey,  SE England     (CLE coordinator)


  (If you would like to listen remotely you could use any one remote

  receiver for your loggings, stating its location and owner and with

  their permission if required.  A remote listener may NOT also use

  another receiver, local or remote, to make further loggings for the

  same CLE)


These listening events serve several purposes. They

• determine, worldwide, which beacons are actually in service and on-the-air so the newly-re-vamped Rxx online database can be kept up-to-date

• determine, worldwide, which beacons are out-of-service or have gone silent since the last CLE covering this range

• will indicate the state of propagation conditions at the various participant locations

• will give you an indication of how well your LF/MF receiving system is working

• give participants a fun yet challenging activity to keep their listening skills honed

Final details can be found at the NDB List website, and worldwide results, for every participant, will be posted there a few days after the event.

The NDB List Group is a great place to learn more about the 'Art of NDB DXing' or to meet other DXers in your region. There is a lot of good information available there and new members are always very welcome. As well, you can follow the results of other CLE participants from night to night as propagation is always an active topic of discussion.

You need not be an NDB List member to participate in the CLEs and all reports, no matter how small, are of much value to the organizers.

Remember - 'First-time' logs are always VERY welcome!

Reports may be sent to the NDB List Group or e-mailed to CLE co-ordinator, Brian Keyte (G3SIA), whose address appears above. If you are a member of the group, all final results will also be e-mailed and posted there.

Please ... give the CLE a try ... then let us know what NDB's can be heard from your location! Your report can then be added to the worldwide database to help keep it up-to-date.

Have fun and good hunting!

Wednesday 8 September 2021

Solar Cycle 25 - Where Are We Headed?


This coming week might be a significant one for the progress of Solar Cycle 25. Going forward, the next two months should give us a good indication of just exactly where our latest cycle is heading.

Cycle 25 is now in its 21st month, having started in November 2019. 

One way to gauge the growth of a cycle is by observing the radio energy it emits at 2800MHz (10.7cm).

This ‘solar flux’ value changes from day to day and from hour to hour, depending mainly on the number of sunspots and their level of activity.

The 2800MHz real-time solar flux units are published three times per day, after being measured at the Dominion Radio Astrophysical Observatory in Penticton, British Columbia. The ‘observed values’ are the actual measured levels while the ‘adjusted values’ reflect compensations for things such as the Sun-Earth distance, background sky noise, solar bursts, atmospheric absorption etc. Of the two values, the ‘adjusted value’ is more descriptive of the Sun’s true behaviour.

Although far from definitive, comparisons with previous cycles may shed some light on Cycle 25’s future. We should remember that almost all predictions from various solar physicists called for another very weak cycle, some saying even weaker than Cycle 24, the poorest in the past 100 years. Of the many predictions, one that varied substantially from the pack was one from Dr. Scott McIntosh’s team.

Their paper called for a very strong cycle, possibly the strongest one ever. We should know shortly which path our latest cycle will favor.

Let’s compare some of the things now known for sure about Cycle 25 with Cycle 19 (strongest ever recorded), Cycles 21, 22 and 23 (all strong, above average cycles that produced several winters of exciting 6m F2 propagation) and the recently-completed Cycle 24 (weakest in past 100 years).

A good indicator of a cycle’s possible future strength is the time that it takes to ramp-up and to really start building. Usually weaker cycles take much longer to do this so one way of looking at Cycle 25’s future might be to see how long it took each of these cycles to reach an adjusted solar flux value of 100. 

Strong cycles are usually fast risers once growth is triggered. Most cycles start with flux values in the 60s and dither around for months or years with short surges into the 80s and 90s before dropping back again. A flux of 100 seems significant when looking at previous cycles as it is often the level where steady upward growth really begins, with fewer surges to a lower level.

Cycle 19

The ‘grandaddy’ of them all. It began in April ‘54 and eventually peaked with a SSN (Smoothed Sunspot Number) of 285. The highest solar flux reached was 345. Cycle 19 took 14 months to hit a solar flux of 100, then dropped back to the 80s for several weeks before ramping up once again. This time it just kept growing. Both hemispheres of the Sun were at similar levels of activity resulting in a cycle with a very strong single peak.

Cycle 21 

Another strong cycle following a weak Cycle 20. It peaked with a SSN of 233 and produced a high flux level of 365.
Cycle 21 took 16 months to reach a solar flux of 100, dropping down to 70s and 80s for three months before taking off.

Cycle 22 

A robust cycle as well with a SSN of 213 and a peak flux of 335. Cycle 22 took 12 months to reach a solar flux of 100, dropping down again for a month before taking off.

Cycle 23

The third in a row of strong cycles but not as strong as the previous two. Cycle 23 reached a SSN of 180 and a flux high of 285 and like the others, produced a lot of exciting fireworks on 50MHz.
It took Cycle 23 just 3 months to reach a flux of 100 where it remained for a week before dropping back to the 70s and 80s for another 10 months. It repeated this 'surge to 100' pattern several times for 8 more months before taking off. Perhaps the original spurt at 3 months was flare-induced and a bit of an anomaly.

Cycle 24

The just-completed weakest cycle in the past 100 years, Cycle 24 had a SSN of 116 and a peak flux of 253. It took Cycle 24 a whopping 26 months to reach a solar flux of 100.

Cycle 25

Our present cycle took just 12 months to reach a flux of 100, remaining above this level for 10 days with a peak value of 115 solar flux units. Dropping back below 100, it remained there for 10 months before this week's present climb back above 100.

This is where we are today, with the solar flux presently at 104, after climbing steadily for the past two weeks. This is an impressive  increase of 30 flux units during the past 27-day rotation period!

Today's Sun

From the above comparison, Cycle 25’s early spurt to a flux level of 100 is very encouraging, while its 10 month sag shortly thereafter was a little discouraging for those expecting things to keep rising.

From looking at previous cycle behaviors, this should now be Cycle 25’s time to continue rising. If the cycle is to be a strong one, it will need to show some continued growth in the next few months. However, one thing seems almost certain ... we are not looking at a repeat of Cycle 24.

All cycles seem content to play in the 70-80 flux zone until triggered into steady upward growth. This triggering or ‘terminator’ event appears to be related to the final end of the previous sunspot cycle and more particularly, to the end of the Sun’s 22-year magnetic (Hale) cycle. The arrival of the terminator is a crucial component in the McIntosh papers and identifying its appearance is difficult, until it becomes obvious by a surge in cycle growth. This is the stage we are at presently.

Cycle 25’s original strong growth surge to well above 100 flux units, just 12 months after starting, had many wondering if this was indeed the terminator’s arrival ... but steady upward growth did not continue. 

This week’s second surge past 100, has posed the question once again. If indeed this is the terminator’s arrival then we should see a continued increase in growth within the next 27-day solar rotation. If this transpires now, it would tend to indicate that Cycle 25 will be above average in strength. If flux values drop again for several months, this would not be a positive sign. For solar observers, the next two months will be of great interest.

The McIntosh et al. paper describes the relationship between the spacing of terminators and the magnitude of sunspot cycles. Their bold prediction relies on this relationship. Low amplitude cycles correspond to widely separated terminators while strong cycles have shorter separations.

The period between terminators (end of previous cycle’s activity) reflects this characteristic.
Monster Cycle 19 had a spacing of just 9.8 years (118 months), while weak Cycle 24 had a 12.8 year (154 months) wait for the terminator. The spacing for strong Cycles 21, 22 and 23 averaged 10.5 years.

The last terminator event was 10.75 years (129 months) ago so the urgency for an imminent arrival, signalling an above average cycle is evident.

One more look at the terminator arrival in terms of a cycle’s start time may also be of interest.

Cycle 19’s terminator event occurred in its 21 month. Cycle 21 waited for 24 months. Cycle 22 and Cycle 23 both waited 27 months, while weak Cycle 24 had a long wait of 37 months. The average wait for all strong cycles (including Cycle 19) is 24.75 months. Excluding Cycle 19 results in a 26 month average. So far, Cycle 25 has been waiting 21 months. This may be another positive indicator of a large cycle if the terminator arrives shortly.

Closely following the level of solar activity and more particularly the growth of a new solar cycle has always been a fascinating aspect of my radio activities. I’m also surprised at the number of hams who seem to take little interest or have little understanding of what is happening on the Sun that plays such a crucial role in the propagation of our signals.

I’ll be following the daily reports on the Sun’s growth carefully over the next few weeks. It's encouraging to see new sunspot regions forming quickly and today another new active area is rotating into view on the eastern (left side) limb. Can you find the new spot in today’s image?

Let’s all hope that Cycle 25 is about to ramp-up for real this time. If the flux remains above 100 going into the fall, we should see some nice transcontinental activity on 28MHz as was the case for Cycle 25's initial flirtation with a flux of 115 in the early winter of 2020. Hopefully the next few rotations will be very exciting!

Wednesday 1 September 2021

e-Bay PCB Thermal Transfer Paper

I recently had the first opportunity to try my e-Bay purchased thermal transfer paper. It was to be used in my iron-on PCB work as a hopeful improvement over what I had been using, just ordinary printer paper. Supposedly the shiny photo-quality papers were proving to be good performers but are expensive. Some have reported good results with glossy magazine paper but my one experience with that was not a pleasant one. Unknowingly, when I had removed the magazine page, a small amount of the sticky adhesive used in the binding process was still on the sheet. Running it through the printer caused it to melt and smear some of the laser cartridge's toner and for the next several weeks, any printing I did had a slight black streak along one edge ... doh!

My new paper from China (free shipping!) was pretty inexpensive and if it offered even a slight improvement, would be well worthwhile. This first use of the paper would be a circuit board for my earlier test-bed GW3UEP 630m transmitter. I had finished designing a PC pattern for it, using MS Paint, and was anxious to see the results.



I decided to use a small separate board for the crystal oscillator-divider so at a later time I could more easily swap it out for a DDS driver. Using a separate board would allow me to do that without disturbing the rest of the transmitter.

I know that a lot of folks turn up their noses at MS Paint but I have always found it to be a very versatile piece of software and have used it for making PC layouts for many years. I also use it for drawing all of the schematics appearing on my website.

After printing the pattern (printer set for maximum resolution and darkest print) and ironing-on the pattern , I allowed the board to cool for several minutes before immersing it, along with the now firmly attached yellow paper, into cold water. The first thing I noticed was how easily the paper came away from the board. It actually 'un-peeled', much like a good quality price tag sticker ... you know, the ones that don't take forever and come off in tiny bits and pieces. It peeled off smoothly with no paper residue left on the board. This was a huge improvement already. There were just a few traces of toner left on the paper as almost all had been transferred to the board.

Once dried, a close examination revealed that I had pressed a little too hard with the iron and there was some evidence of  'squeeze-out' along the edges of some lines. I also found one or two very small thinner areas that probably required going over with a permanent-ink black marker pen just to make sure that those spots did not get etched. Over all I was extremely pleased with the paper and will be using it from now on.

Another recent change in my PC etching regime has been a switch from the old and messy Ferric Chloride standby to a combination of Hydrogen Peroxide and Muriatic acid. Not only does it seem to etch more cleanly (no undercutting) but it also etches very quickly and without any solution warming needed. This board was completely etched in just over 4 minutes.

The chemicals used in this method are inexpensive and are readily available at the drugstore and at the hardware store. There are numerous web-descriptions of this particular etching process but this site seems to cover the basics nicely.

The completed board turned out as shown here, using the 'dead-bug' style of mounting parts:


The CD4060 not only functions as a crystal oscillator but also as a versatile frequency divider. As well as fundamental frequency output, ten different 'divide-by' functions are available depending in which output pin is chosen. These range from divide-by 16,384 to divide-by 16. This circuit uses the latter, dividing the 7.6 MHz crystal down to 475 kHz at pin 7.

In summary, I can highly recommend the e-Bay yellow thermal transfer paper when used for this method of making PCB's and is much cheaper than buying photo-quality printing paper.