Solar Update 09/11/2020
Tad Cook, K7RA, Seattle, reports: An extended lull in solar activity persists. The smoothed sunspot minimum occurred last December, but the flurry of moderate sunspot activity in August has not continued.
An event to look forward to is the autumnal equinox, which occurs at 1330 UTC on Tuesday, September 22. We should see a seasonal improvement in HF propagation around that date because the northern and southern hemispheres are bathed in roughly equal solar radiation, enhancing north-south propagation.
Thursday, September 10 was the 20th consecutive day with no sunspots, but Spaceweather.com reported a small sunspot with a Cycle 25 magnetic signature may be forming in the sun’s southeastern quadrant. As of Thursday night it was still too small to merit numbering.
Average daily solar flux barely budged from 69.6 to 69.7. Geomagnetic indicators were very quiet, with average daily planetary A index declining from 13.1 to 4.4. As with last week’s forecast, predicted solar flux is 70 on every day over the next 45 days, September 11 – October 25.
Predicted planetary A index is 5 on September 11 – 17; 8 on September 18 – 19; 5 on September 20 – 22; 8, 10, and 15 on September 23 – 25; 10, 25, 15, and 10 on September 26 – 29; 5 on September 30; 8 on October 1; 5 on October 2 – 14; 8 on October 15 – 16; 5 on October 17 – 19, and 8, 10, 15, 10 and 25 on October 20 – 25.
F.K. Kanda, OK1HH, in the Czech Republic has shared geomagnetic activity forecast for September – October 6.
The geomagnetic field will be:
- quiet on September 11 – 13, 16 – 17, 20 – 21
- quiet to unsettled on September 14, 22 – 25, 29, October 1 – 2
- quiet to active on September 15, 18 – 19, 26 – 27, (October 5 – 6)
- unsettled to active (September 28 – 30; October 3 – 4)
- active to disturbed not expected
Solar wind will intensify on September (15, 19,) 22 – 23, (October 3 – 4)
Note: Parentheses mean lower probability of activity enhancement.
Frank Donovan, W3LPL shared this on September 6:
“Exactly 3 years ago, on September 6, 2017, the sun ejected the strongest solar flare and earth-directed coronal mass ejection (CME) of Solar Cycle 24. Solar region 2673 produced four X-class solar flares, including a massive X-class solar flare of magnitude 9.3, from 1153 to 1210 UTC.
Just over 8 minutes later, powerful hard X-rays from the flare increased D-layer ionization by several orders of magnitude, completely blacking out HF skywave propagation on the daylight side of Earth for about an hour — an event called a “sudden ionospheric disturbance” (SID).
Solar flares are commonly followed by CMEs. Solar region 2673 ejected powerful Earth-directed CMEs on September 6, 2017, causing visible aurora on September 7 and 8, and a severe geomagnetic storm the planetary Kp index reached magnitude 8 on September 8.
See the SpaceWeatherLive.com YouTube presentation.
The strongest solar flare measured in modern times was an X28 flare on October 28, 2003, which blacked out HF skywave propagation on the sunlit side of Earth for several hours. Extremely powerful CMEs on October 28 and 29 caused severe geomagnetic storms on October 29, 30, and 31, and the Kp index reached magnitude 9 on all 3 days.
A 3-hour video from WX6SWW! Coronal Holes and Sources of the Solar Wind — Part 2.
Sunspot numbers for September 3 – 9 were 0, 0, 0, 0, 0, 0, and 0, for a mean of 0. The 10.7-centimeter flux was 70, 69.7, 69.2, 69.5, 70.2, 69.9, and 69.7, with a mean of 69.7. Estimated planetary A indices were 4, 8, 6, 4, 4, 4, and 1, with a mean of 4.4. Middle latitude A index was 3, 9, 7, 5, 5, 4, and 1 with a mean of 4.9.
For more information concerning radio propagation, visit the ARRL Technical Information Service, read “What the Numbers Mean…,” and check out K9LA’s Propagation Page.
A propagation bulletin archive is available. Monthly charts are no longer be updated on this page. For customizable propagation charts, visit the VOACAP Online for Ham Radio website.
Instructions for starting or ending email distribution of ARRL bulletins are on the ARRL website.
Share your reports and observations.
SOURCE:ARRL
Review
New Yaesu FTdx 10 Hybrid SDR Ham Radio Review
Today we take a look at the interesting freatures on the Yaesu FTdx-10 and I give you my review. Also, I explain why the FTdx-10 is a Hybrid Software... Read more
Yaesu FT-991A Unboxing
The FT-991A is the next generation in all mode, all band MF/HF/VHF/UHF transceiver with C4FM (System Fusion) Digital capability. The FT-991A includes... Read more
My Wife Bought More Radio Gear On Wish and Ali Express
My wife surprised me at the end of 2020 with a new random box of goodies from Wish and AliExpress. Today we unbox some of these ODD radios and radio a... Read more
Ailunnce HD1 DMR – Review and how to build a DMR codeplug
“The Ailunce HD1. It’s a DMR Radio. It’s a Ham Radio. It’s both. This promises to be the next evolution in Dual Band DMR handh... Read more
Equipment
Kenwood Communications Headphones HS-5
Headphones HS-5 Kenwood HS-5 deluxe communications headphones are engineered and tuned for radio communications purposes to provide distinctive... Read more
Xiegu X108 QRP Transceiver Kit 9 Bands – AM – SSB – CW
Xiegu X108 QRP Transceiver Kit 9 Bands – AM – SSB – CW 1 – 20 watts The X-108 is a single-conversion transceiver for all ama... Read more
5W CW Transceiver kit assembly instructions – QRP Labs
Easy to build, single-board design, 10 x 8cm, all are controls board-mounted Professional quality double-sided, through-hole plated, silk-screen print... Read more
AR-ALPHA 10kHz-3500MHz, Digitally processed Professional Grade, Base Type
AR-ALPHA 10kHz-3500MHz, Digitally processed Professional Grade, Base Type Read more
OM-Power 4001A Fully Automatic HF Amplifier
OM-Power 4001A Fully Automatic HF Amplifier General description and the advantages of the OM4001A amplifier The OM Power model OM4001A is an automatic... Read more
Antenna
Simple Multi-Band Vertical Dipole by DJ0IP
Simple Multi-Band Vertical Dipole This simple multi-band vertical described below will give you very good performance on 40 through 10m and eve... Read more
FX771 MetroPWR Overview
Technical Features METER METROPWR FX771 Coverage 1.8/55 MHz 160/6mt + VHF/UHF (optional) Measure Power AVG, PeP, dBm, R, Z, X , SWR, ReturnLoss Po... Read more
AG6IF BUILT 3DFL, 2 METER FULL WAVE HAM RADIO ANTENNA, WORKS ON 440 70CM ALSO
You are looking at a AG6IF built 2 meter ham radio antenna. 3 dimensional folded Full wave loop design. Rugged and solid with soldered copper connect... Read more
Basics of building HF/VHF cubical quad antennas
Basics of building HF/VHF cubical quad antenas Read more
App - Mobile
Training fast CW on Android (Koch method)
The user starts by recognizing only two letters, M and K, at high speed (at least 20WPM) on a 5 minutes session. When she or he will be able... Read more
Hamradio Line Loss Calculator for iOS devices
Coax Line from Federico Romano, IW2MVI is a simple and fast app that allow you to calculate the loss of your coax line and calculate power output from... Read more
Rfinder for Visually Impaired on Android
Rfinder Tom W3ZX, a visually impaired ham gives a great demo on Android using TalkBack for the visually impaired. See More: http://www.rfinder.net/blo... Read more
EchoHam version v2.10 has been released
EchoHam allows Amateur Radio operators to use the Echolink network from their Mac. You must be a licensed Amateur Radio operator to use this software.... Read more