The K7RA Solar Update

No sunspots appeared over the past week, and in the prior week there were only two days with sunspots, so average daily sunspot number declined from 3.1 to 0.Average daily solar flux nudged higher, but just barely, from 67.6 to 67.8.

Geomagnetic indicators were much lower this week, with average daily planetary A index retreating from 14.4 to 6.3, while the mid-latitude average went from 11 to 5.3.

Predicted solar flux for the next 45 days is 68. That’s correct, on every day for the next month and a half, October 11 through November 24 the solar flux is forecast to be 68. This is in line with recent conditions.

Predicted planetary A index is 5 on October 11-12, 8 on October 13-14, 5 on October 15-20, then 12, 5 and 5 on October 21-23, then 18, 25, 12, 10 and 8 on October 24-28, then 5 on October 29 through November 3, 8 on November 4-5, 5 on November 6-8, then 8 on November 9-10, 5 on November 11-16, then 12, 5 and 5 on November 17-19, then 18, 25, 18, 10 and 8 on November 20-24.

F.K. Janda, OK1HH, sent this geomagnetic activity forecast for the period October 11-November 5, 2019.

Geomagnetic field will be:
Quiet on: October 16-17, 29-30
Quiet to unsettled on: October 15, 18-20, 22-23, November 1
Quiet to active on: October 11-14, 27-28, 31, November (2-5)
Unsettled to active on: October 21, 26
Active to disturbed: October 24-25

Solar wind will intensify on: October 11 (-14,) 21-26

Parenthesis means lower probability of activity enhancement.”

Even more news on huge solar blasts in the past:

Mike Schaffer, KA3JAW, of Easton, Pennsylvania reported: “Yesterday, Friday, October 4, the same 11 meter band double-hop Es event (reported last week) repeated itself.

“This time it started later during the day, sometime prior to 4:45 PM and vaporized at 6:10 PM ET. From 5:14 PM onward, local (within 10 miles) 11-meter operators were heard mixing with the Puerto Rican DX.

“The signal strength was fairly-good, at times slow short duration fading with slight distortion due to multipath propagation.

“Other signal reports included:

● 2136 UTC WP4O FK68ke 28.075.7 DIGI AB1HL FN42kj 2717 km

● 2142 UTC WP4O FK68ke 28.075.7 DIGI W1ZQ FN42fu 2773 km

● 2151 UTC W1NT FN42lu 28.025.0 CW HK1MW FK20lt 3582 km CW

● WP4O Bayamon, PR – AB1HL Cambridge, MA, 1688 miles

● WP4O Bayamon, PR – W1ZQ Amherst, NH, 1723 miles

● W1NT Newton, NH – HK1MW Barranquilla, Colombia, 2225 miles

“On Wednesday, October 9, the 11-meter band opened with double-hop Es down to the northern Caribbean Sea, from Cuba over to Puerto Rico.

“It started at 4:40 PM ET (2040 UTC) and vaporized at 6:04 pm (2204 UTC), twenty-eight minutes prior to local sunset.

Signal strength ranged from Faint (1) to Fair (5).”

Ken, N4SO, of Alabama sends us his 17-meter notes: “I was on 18.100 MHz using FT8 on October 7. The band opens near sunrise each day, with a variety of European stations, including Ukraine and Oman. Wales appeared first today. When the band opened, there are no US or South American stations, but they appeared about two hours later.

“There are very few Maritime Mobile stations on FT8. However, Vladimir,  UW5EJX/MM, was operating from a tanker and we made contact at 1846 UTC.

184645 -13  0.3 2649 ~  CQ UW5EJX/MM

“Using 15 W to my half-square antenna, I also managed to pick up…

120630 -15  0.1 1047 ~  CQ DX GW0PLP IO72  Wales
133430   2  1.5 1713 ~  N4SO OM3SEM 73  (Slovak Rep.)
135700  -1  0.1 1606 ~  <N4SO> HB9SPACE RR73  (Switzerland)
141530  -9  0.4 1551 ~  N4SO EA4HBK RR73 (Spain)
140730 -17  0.3 1737 ~  CQ E75C JN93       Bosnia-Herzegovina
143700 -11  0.1 2378 ~  N4SO EB3JT JN01  (Spain)”

Martin McCormick, WB5AGZ, wrote: “I believe there is a way to tell if the propagation one is hearing is Sporadic E or F2.

“When Sporadic E occurs, the path goes from the transmitter to a patch of sky in which the E layer is ionized to form a reflective surface like a mirror which bounces it back to Earth somewhere else. It is a simple path and the resulting echo fades up and down in strength but there is no selective fading to give that characteristic shortwave sound, as if somebody was continually twisting the tone controls. The signal just gets stronger and weaker.

“F2 reception is more complex because there is more than one F layer. Since radio signals are nothing more than a different color of light, they travel at the speed of light with nulls and nodes that enhance or nullify the carrier on any given frequency from second to second. This is what can briefly make an AM signal sound like sideband and, if you switch to sideband mode, you may hear a tinny-sounding restoration of the AM audio because the null of the carrier only kills the carrier, not the side bands.

“The effect is much like sweeping a RF notch filter across an AM signal because that is what the physics of the multiple reflective layers which may be many miles apart are doing to the signal.”

Here is the latest video from Tamitha Skov, WX6SWW:

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Sunspot numbers for October 3 through 9, 2019 were 0, 0, 0, 0, 0, 0, and 0, with a mean of 3.1. 10.7 cm flux was 68.2, 68.1, 67.8, 67.4, 67.7, 67.1, and 68.1, with a mean of 67.6. Estimated planetary A indices were 5, 7, 7, 5, 6, 5, and 9, with a mean of 14.4. Middle latitude A index was 5, 6, 6, 5, 4, 4, and 7, with a mean of 11.

Author: WT5X