Higher Bands Will Pick Up this Fall, Data Suggest Smaller Solar Cycles Lie Ahead

Propagation guru Carl Luetzelschwab, K9LA, says that, while conditions on 12 and 10 meters will pick up as they always do in the fall, F2 propagation on those bands will decline thereafter, with only sporadic E during the summer months as a possible saving grace. On the other hand, the lower bands — 160, 80, and 40 meters — should be good going forward, and 20 and 17 meters will be the mainstays of daylight HF propagation. Luetzelschwab made these observations during an August 23 World Wide Radio Operators Foundation (WWROF)-sponsored webinar “Solar Topics — Where We’re Headed.” He said data suggest that Cycle 24, the current solar cycle, will bottom out in 2020, and advised that radio amateurs may need to lower their expectations on the higher bands (and 6 meters) looking beyond that.

“I think the only conclusion we can make with some confidence is that we are headed for some small cycles,” he told his audience. He cited various evidence related to the Sun’s polar fields — which appear to be decreasing in strength, A index trends, and cosmic ray data to support his assertion. Luetzelschwab cautioned, however, that past performance does not necessarily predict future performance.

“There seems to be a good correlation between how long a solar minimum is and the next solar cycle,” said Luetzelschwab. “The longer you spend at solar minimum, the smaller the next cycle.”

He observed that hams active since the 1950s and 1960s have experienced short inter-cycle solar minimums of approximately 2 years, until the one between Cycle 23 and Cycle 24, which lasted about 4 years. He also allowed that the science is not fully understood, and that some things appearing to be patterns may just be coincidences.

On the other hand, he said, it looks like the downward trend of disappearing sunspots has leveled off, suggesting that Cycle 25 may see a lower smoothed sunspot number as opposed to zero or near-zero sunspots.

Counting those sunspots can be a subjective business. “That’s a tough job,” he said of the task, noting that it appears observer bias also has been a factor over the years, affecting historical sunspot data. “We now have new corrected data that are believed to be more accurate.”

Luetzelschwab’s article “The New Sunspot Numbers,” appearing in the October issue of QST, will discuss the new sunspot numbers.

Luetzelschwab cited historical sunspot cycle data going back centuries — including the “Maunder Minimum” of zero and near-zero sunspots between the years 1645 and 1715 and a later, less-drastic “Dalton Minimum.” He pointed out that over the last 11,000 years, 19 notable grand maximums — including Cycle 19 and the cycles around it — and 27 notable grand minimums were recorded. “We’re likely to have more of both grand maximums and grand minimums in the future,” he predicted. The current system of numbering sunspot cycles begins with Cycle 1 in the mid-18th century.

“We don’t fully understand the process inside the Sun that makes solar cycles,” Luetzelschwab said. “Thus, you should exercise caution with statements seen in the news.” 

More

The WSPR Heard ‘Round the World

March 28, 2019 No comments

 Are you curious about the mysteries of signal propagation, or maybe wondering how well your antenna is working? The answer may be just a “WSPR... Read more

Comparing the RFinder H1and M1 Devices

March 20, 2017 No comments

In this episode, I talk about the 2 RFinder devices – the original H1, and the new M1. The M1 is now my daily carry Smartphone and 2-way radio.... Read more

Soundcards and the SignaLink USB

October 21, 2020 No comments

Soundcards and the SignaLink USB  Read more

The new Malahit-DSP: A portable all-in-one wideband SDR receiver

November 12, 2019 No comments

Technical Specifications 1 MHz to 1000 MHz. Bandwidth 160 kHz. Modulation types AM, WFM, NFM, LSB, USB. Powered by one Li-ion cell. Consumption up to... Read more

Xiegu GSOC First Look! Feature Walkthrough

November 05, 2020 No comments

Xiegu GSOC First Look! Feature Walkthrough Read more

ZUMSpot RPi Hotspot Review

January 22, 2019 No comments

HRO has an exclusive new ZUMSpot with an LCD screen   The ZUMspot RPi is an advanced radio module board. Paired with a Raspberry Pi and the MMDVM soft... Read more

Surecom SF-401plus frequency counter CTCSS decoder

June 21, 2016 No comments

Introduction:　 The frequency meter capable of measuring the parameters of the frequency of the continuous carrier signal walkie-talkies , with signal... Read more

“Generators” is the topic of the new (June 22) episode of the “ARRL The Doctor is In” podcast.

June 22, 2017 No comments

“Generators” is the topic of the new (June 22) episode of the “ARRL The Doctor is In” podcast. Listen…and learn! Sponsored by DX Engineering, “A... Read more

Demo of tuning the Radiuno BITX40 by W5KUB

January 29, 2017 No comments

“At first the tuning of the Radiuno seemed like it has a mind of its own. But after working it a few times you learn how to control it.” Read more