ARRL

The American Radio Relay League (ARRL) is the national association for amateur radio, connecting hams around the U.S. with news, information and resources.
  1. Excellent HF conditions greeted hams in the ARRL 10-Meter contest
    last weekend. Recent indicators show a sudden shift to two digit
    daily sunspot numbers from three, and although there is nothing
    significant about 100, it makes one notice.

    All daily sunspot numbers this week were 97 or less.

    Perhaps this indicates a move off of solar maximum, or to a future
    with a second maximum.

    Solar activity was way...

  2. Average daily sunspot number plummeted to 104.4.

    Weekly Commentary on the Sun, the Magnetosphere, and the Earth's Ionosphere for December 12, 2024 from OK1HH:

    "The high solar activity in October this year suggests that this may have been the peak of an 11-year cycle. This is not to say that solar activity will not continue to rise. On the contrary, it may well be that the first maximum of the...

  3. The ARRL Teachers Institute on Wireless Technology (TI) continues to grow. Fresh off a highly successful YouTube telethon that raised more than $41,000 for the program, some of next year’s dates have been announced. Applications are now open.

    The program is growing, and educators will have the opportunity to attend sessions around the country. “We love having the teachers here at ARRL Headquarte...

  4. We are at the peak of Solar Cycle 25, and the 10-meter amateur radio band has been providing impressive propagation lately. Recent reports of “wide open” band conditions make this weekend’s ARRL 10-Meter Contest a great opportunity to take advantage of the best conditions of a generation. “I’ve been leaving the mobile radio on 10-meters for the drive into work each day,” said ARRL Regulatory an...

  5. Solar activity seems to have dropped dramatically from a recent peak. Are we over the cycle peak and headed down again? Too early to say.

    Daily average sunspot numbers this week sank to 120.1.

    Predicted solar flux is 175 on December 6 to 8, 170 on December 9 and 10, 175 on December 11 and 12, and 205 on December 13 to 17.

    Predicted planetary A index is 8 on December 6 and 7, 5 on December to...