The
Eastern Iowa DX Bulletin
Number
295, October 10, 2025
Craig Fastenow, KØCF, Editor
This bulletin is a compilation of currently active DX operations (or those that will become active within the current week) from recent issues of the three DX bulletins listed below and other sources. Credit for the source is given at the end of each article.
Articles are ordered by the entity's callsign prefix from the ARRL DXCC Entities List. Callsigns used are in bold with dates of operation highlighted in red. Clickable links are provided for QSL and other information wherever possible. Note that articles may be edited for grammar, language, style and accuracy and will remain in The Bulletin while active; articles that are announcements of ongoing operations, or that have no specified end date, will be removed after three weeks.
Also included is a Propagation section, updated daily; and a Contest Calendar of upcoming popular contests.
DX News
items are courtesy of:
The ARRL DX Bulletin
This bulletin is available via email
subscription only. See
http://www.arrl.org/bulletins
to subscribe. (The online archive is no
longer updated.)
425 DX News, A.R.I. DX Bulletin (425DXN)
Edited by Mauro Pregliasco, I1JQJ
& Valeria Pregliasco, IK1ADH
425 DX News Home Page: https://www.425dxn.org/
425 DX News Google Group: https://groups.google.com/g/425eng
DX Newsletter (DXNL)
Edited by Andreas Salder, DK5ON
A weekly service of DARC Committee
"DX", http://www.darcdxhf.de
Propagation data is from:
National Oceanic and
Atmospheric Administration's
Space Weather Prediction
Center
Dr. Tony Phillips' SpaceWeather.com,
used by permission
Contest data
courtesy of the WA7BNM
Contest Calendar
DX
News
5H, TANZANIA.
Maurizio, IK2GZU will be active again as 5H3MB from Tanzania
from October 16th to
November 20th,
while doing volunteer work at a local school. In his spare time, he
will operate SSB, CW and digital modes on 80-10 meters. QSL via ClubLog's OQRS,
LoTW, and eQSL, or via IK2GZU.
-[425DXN # 1795 September 27, 2025] (1010-1121)
5R,
MADAGASCAR. Eric, F6ICX will be active again as 5R8IC from
Sainte-Marie
Island (AF-090), Madagascar from October until late December
or early
January. He will operate CW with some FT8 (F/H) and SSB on 40-10
meters; during the last two weeks of December and maybe the first week
of January he will also be QRV via QO-100. QSL via LoTW, ClubLog's OQRS,
or via F6ICX.
-[425DXN # 1795 September 27, 2025] (1003-1017)
7Q, MALAWI.
Zachary, KJ5BIN, has set up a remote station during his volunteering at
a hospital in Embangweni, which he now uses with the callsign 7Q5BIN on 10 and 6m
(SSB, FT8/4). QSL direct via KJ5BIN, OQRS.
-[DXNL # 2477 September 24, 2025] (0926-1017)
9A, CROATIA.
Special callsign 9A1ØSOTA
celebrates ten years of SOTA Croatia. Look for activity from October 1st to September 30, 2026. A
certificate will be available for contacts made between October 1st and
December 31st, 2025. See https://9aff.wordpress.com/
for information. QSL via LoTW.
-[425DXN # 1795 September 27, 2025] (0926-1017)
9M, MALAYSIA.
Members of the DX club in Kulai operate for a scout meeting as 9M4JOTA from October 10th to 20th.
See https://www.qrz.com/db/9M4JOTA.
QSL via qrz.com.
-[DXNL # 2479 October 8, 2025] (1010-1024)
9N, NEPAL.
Suvarna, OMØGA has moved permanently to India, where he holds the
callsign VU3OPT. He will be QRV as 9N/OMØGA
from September 2nd
to October 13th. See https://www.9n7ga.com
for more information.
-[425DXN # 1794 September 20, 2025] (0919-1017)
C2, NAURU.
Phill, C21TS
now expects to remain on Nauru (OC-031) until November 30th.
After a 2-month leave, "I'll probably be back for a few months from
February 2026 with minimal gear", he says. He will be QRT for good no
later than June 2026. QSL via LoTW, or via MØOXO's OQRS.
-[425DXN # 1795 September 27, 2025] (0926-1130)
CEØX, SAN FELIX
& SAN AMBROSIO IS. The DXpedition to Sam Ambrosio
(SA-013), scheduled for October/November 2025 is delayed
until January/February 2026.
The operating permit is valid from January 12th until February 15th,
allowing for at least 25 days on the air. Most of the necessary gear,
which is also to include a Radio-in-a-box rig for remote operation,
will be transported to Robinson Crusoe Island (CEØZ), the point of
departure for the expedition, during the next weeks. See also: https://www.sanambrosio-project.com.
QSL via MØURX's OQRS,
LoTW.
-[DXNL # 2479 October 8, 2025] (1010-1017)
CT3, MADEIRA IS.
Georg, DD8ZX, is going to pay Madeira (AF-014) a visit from October 3rd to 16th,
signing CT9/DD8ZX.
QRV mostly on FT8 with 10W and a wire antenna. QSL via bureau.
-[DXNL # 2479 October 8, 2025] (1010-1017)
DL, GERMANY.
The special event stations DC75DARC,
DD75DARC, DK75DARC, and DR75DARC continue to
celebrate DARC's 75th anniversary until the end of October.
An award program, involving QSOs with DARC members, DARC officials, and
club stations is also available via the DARC Community Logbook (DCL).
QSL for all for callsigns via DL2VFR.
-[DXNL # 2477 September 24, 2025] (0926-1031)
DXCC TOP TWENTY.
Here are the top 20 entities on ClubLog’s "DXCC Most Wanted" list as of
October 10, 2025:
1. P5 DPRK
(North Korea) 11. VKØM Macquarie
Island
2. BS7H Scarborough
Reef 12.
KH4 Midway Island
3. CEØX San Felix
Islands 13. PYØS Saint Peter
And Paul Rocks
4. BV9P Pratas
Island 14.
KP5 Desecheo Island
5.
KH7K Kure
Island
15.
VPØS South Sandwich Islands
6.
KH3 Johnston
Island 16.
ZL9 New Zealand Subantarctic
Islands
7. 3Y/P Peter 1
Island 17.
FK/C Chesterfield Islands
8. FT5/X Kerguelen
Island 18.
VKØH Heard Island
9. YVØ Aves
Island
19.
FT/T Tromelin Island
10. 3Y/B Bouvet
Island 20.
EZ Turkmenistan
For the complete list, see
https://clublog.org/mostwanted.php
-[KØCF October 10, 2025 (1010-1031)
E5/N, NORTH COOK
IS. Team E51MWA
(Robert N7QT, Jack N7JP,
James KC7EFP, Brian N9ADG, and YL operators Robin WA7CPA and Violetta
KN2P) will be active from Manihiki Atoll (OC-014), North Cook Islands
on October 9th-20th.
They will operate CW, SSB, and FT8 (F/H) on 160-10
meters with three stations. See https://www.e51mwa.com
for more
information and updates. Selective LoTW upload will be in place. QSL
via MØURX's OQRS.
-[425DXN # 1787 August 2, 2025] (1003-1024)
E6, NIUE.
The Rebel DX Group has been active as E6AD from Niue
(OC-040) since
October 7th. This is a 2-man activity. "Digital is a
priority", they say, "some CW and SSB will be done from time to time".
See https://www.qrz.com/db/E6AD
for more information. QSL via ClubLog's OQRS.
-[425DXN # 1797 October 11, 2025] (1010-1031)
EA, SPAIN.
Special callsign AN5CV
will be activated on October
6th-12th to celebrate the Day of the Valencian Community.
Certificates and eQSLs will be available on HamAward: https://hamaward.cloud/.
-[425DXN # 1796 October 4, 2025] (1003-1017)
F, FRANCE.
Michel, F8GGZ will be active as TM8ØUCO
on October 12th-19th
for the 80th anniversary of UNESCO, the UN Educational, Scientific and
Cultural Organization that promotes cooperation in education, science,
culture and communication. He will operate SSB and CW on 80-10m. QSL
via eQSL only.
-[425DXN # 1797 October 11, 2025] (1010-1024)
H4, SOLOMON IS.
Bernhard, DL2GAC, is QRV as H44MS
from Malaita Island (OC-047) until
November 25th. Activity is on 80 to 6 meters using SSB and
FT8. QSL to DL2GAC.
-[ARRL DX Bulletin # 41 October 9, 2025] (1010-1128)
HH, HAITI.
Members of Radio Club d'Haiti will be active as 4V1SB on October 1st-31st.
The special callsign commemorates Simon Bolivar, who led several South
American countries to independence from the Spanish Empire. Haiti
played a crucial role in Bolívar's revolutionary efforts by offering
him refuge and providing significant military support. QSL via N2OO.
-[425DXN # 1796 October 4, 2025] (1003-1031)
HK, COLOMBIA.
Special callsigns 5J3HD
and 5K3CD
celebrate Hispanicity Day and Columbus Day for members of the
Liga de Radioaficionados de Bogota (HK3LRB) on October 11th-13th.
QSLs via LoTW, QRZ Logbook, eQSL, or direct to HK3LRB.
-[425DXN # 1796 October 4, 2025] (1010-1017)
HKØ, SAN ANDRES
& PROVIDENCIA. Team 5KØUA (HK1T, HJ1YL,
K2BB and UUØJR, plus possibly US7UX, VA2WA and WB2AA) will be active
from San Andres Island (NA-033) from October 15th to November 3rd.
They will operate CW, SSB and FT8 on 160-10 meters, and will
participate in the CQ WW DX SSB Contest (October 25th-26th). See http://imdx.org/
for more information. QSL via ClubLog's OQRS
and LoTW.
-[425DXN # 1797 October 11, 2025] (1010-1107)
HP, PANAMA.
Alex, F4GHS will be active as HP3/F4GHS
from Hermosa Bay in the Chiriqui Province of Panama on October 9th-17th.
He will be QRV mainly on 20 meters SSB. QSL via F4GHS.
-[425DXN # 1797 October 11, 2025] (1010-1017)
I, ITALY.
Members of ARI Gorizia (IQ3GO) will be active as II3GONG from October 1st to December 29th.
The special callsign's suffix stands for Gorizia (Italy) and Nova
Gorica (Slovenia), the first cross-border European Capital of Culture.
A certificate will be available, see https://www.qrz.com/db/II3GONG
for information. QSL via the bureau and eQSL.
-[425DXN # 1795 September 27, 2025] (0926-1024)
I, ITALY.
Celebrating 130 years of radio and IARU's centenary, several special
callsigns will be in use from September
15th to October 15th: IIØIARU
(Sardinia), II1IARU,
II2IARU, II3IARU, II4IARU, II5IARU, II6IARU, II7IARU, II8IARU, II9IARU, IRØIARU, IR2IARU, IR3IARU, IR7IARU and IR8IARU, as well as II1RVCO, II2RBUS, II3RTRE, IR2RGAL, IR2RIMV and IR2RMAG. See https://www.ari.it/
for more information. Certificates and eQSLs will be available on
HamAward.
-[425DXN # 1793 September 13, 2025] (0912-1017)
J3,
GRENADA. Eric, GM5RDX and Graham, 2MØIJU will be active as
J38DX and
J38LD,
respectively, from Grenada (NA-024) on October 8th-15th.
They
will operate mainly SSB, with some FT8, on 80-6 meters. QSL for both
callsigns via MØOXO's OQRS.
-[425DXN # 1795 September 27, 2025] (1003-1017)
JA, JAPAN.
The two special event callsigns 8K3EXPO
& JA3XPO
will conclude
their activities for the EXPO 2025 exhibition in Osaka on October 13th.
QSL via bureau, LoTW.
-[DXNL # 2479 October 8, 2025] (1010-1017)
JA, JAPAN.
Mitsuru, JE1HXZ will be active as JE1HXZ/6
from Kita-Daito Island (AS-047) on October 8th-15th.
He will operate CW, SSB, RTTY and FT8/FT4 on 160-6 meters. QSL via LoTW.
-[425DXN # 1796 October 4, 2025] (1003-1017)
JA, JAPAN.
Take, JI3DST will be active as JS6RRR
from Miyako Island (AS-079) from September 26th until December
3rd. He will operate SSB, CW and FT8 on 40-6 meters. Other
callsigns to be used are JI3DST/6,
JJ5RBH/6, JI3DST/p and JJ5RBH/p. QSOs will
be uploaded to ClubLog and LoTW.
-[425DXN # 1796 October 4, 2025] (1003-1031)
JD1/M, MINAMI
TORISHIMA.
Take, JG8NQJ has been back to the weather station on Minami Torishima
(OC-073) since September 18th, and will remain there until December,
his QSL manager reports. Take is QRV as JG8NQJ/JD1
in his limited spare time. He operates CW and some FT8 (please note
that he wants you to call with your signal report, not your grid
square). QSL via JA8CJY
(direct), JG8NQJ
(bureau) and LoTW.
-[425DXN # 1794 September 20, 2025] (0919-1024)
JW,
SVALBARD. Look for JW7XK, JW9DL and JW6VM to be active
from the
Svalbard Amatorradioklubb in Longyearbyen (EU-026), Svalbard on October
8th-13th. They will participate in the Scandinavian Activity Contest,
SSB (October 11th-12th) as JW5X.
Outside the contest, JW9DL
will be
mostly active on FT8 and FT4, JW6VM
on CW, and JW7XK
via satellite
(RS-44) on CW, SSB and FT4. QSL JW7XK via LA7XK, ClubLog's OQRS
and
LoTW. QSL JW9DL via LA9DL, ClubLog's OQRS
and LoTW. QSL JW6VM via
LA6VM. QSL JW5X
via ClubLog's OQRS,
LoTW, or via LA5X.
-[425DXN # 1795 September 27, 2025] (1003-1017)
K,
UNITED STATES. Radio club NI6BB aboard the USS
Iowa marks the 200th
anniversary of the US Navy from October
4th to 19th. See also
https://biara.org.
-[DXNL # 2478 October 1, 2025] (1003-1024)
KHØ,
MARIANA IS. Harry, JG7PSJ is QRV as WHØRU from Saipan
(OC-086)
until October 12th.
Activity is on 40 to 10 meters using CW, SSB, and
various digital modes. QSL via LoTW or direct to JG7PSJ.
-[ARRL DX Bulletin # 40 October 2, 2025] (1003-1017)
LX, LUXEMBOURG.
Special callsigns LX25GDH
(September 3rd -
October 3rd) and LX25GDG
(October 3rd -
November 3rd)
are the for Radioamateurs du Luxembourg (RL, Luxembourg's IARU society)
to mark the "Trounwiessel" - the accession to the throne of Prince
Guillaume, who is set to become Grand Duke on October 3rd upon the
abdication of his father the Grand Duke Henri. QSL via ClubLog's OQRS.
-[425DXN # 1792 September 6, 2025] (0905-1107)
ON, BELGIUM.
The ONZ Oostkust Radioclub (ON6HC) will be active on all bands and
modes as OR81C
from October 15th to
November 14th
to commemorate the 81st anniversary of the liberation of the region of
Knokke-Heist by Canadian troops in 1944. A certificate will be
available: https://www.onz.be/or81c-award-request/.
QSL via eQSL.
-[425DXN # 1797 October 11, 2025] (1010-1114)
OX, GREENLAND.
Bo, OZ1DJJ will be active again as OX3LX
from Greenland (NA-018) from October
3rd to 21st. As always, this will be a working trip, and
he will be QRV only in his spare time. QSL via LoTW, ClubLog's OQRS
or via OZØJ.
-[425DXN # 1796 October 4, 2025] (1003-1024)
PA, NETHERLANDS.
Volker, DL1WH will be active holiday style as PA/DL1WH from Texel
Island (EU-038) on October
11th-24th. He will operate mainly CW, with some SSB. QSL
via DL1WH.
-[425DXN # 1797 October 11, 2025] (1010-1024)
PA, NETHERLANDS.
Special callsign PA8ØVERON
celebrates the 80th anniversary of the Dutch IARU society, Vereniging
voor Experimenteel Radio Onderzoek in Nederland (VERON). QSL via PA1AW.
-[425DXN # 1796 October 4, 2025] (1003-1024)
PJ2, CURACAO.
Andre, PD1DRE, is currently vacationing on Curacao (SA-099) and signs PJ2/PD1DRE until October 28th
on 40-10m (SSB, FT8), mostly during his evening and night hours. QSL
via eQSL.
-[DXNL # 2479 October 8, 2025] (1010-1031)
PY, BRAZIL.
Special callsign PX1ØØIARU
was issued to the Liga de Amadores Brasileiros de Radio Emissao (LABRE)
which is hosting the IARU Region 2 General Assembly. Look for activity
on "all bands, all modes and satellite" until October 12th.
A certificate can be requested by contacting awards@labre.org.br
with the QSO details. QSL via LoTW; paper cards will not be available.
-[425DXN # 1797 October 11, 2025] (1010-1017)
PYØF,
FERNANDO DE NORONHA. Mario, PY2DV as PYØFB (80-6 meters
SSB and some
FT8) and Bruce, PY2BS as PYØFBS
(23cm EME) will be active from Fernando
de Noronha (SA-003) on October
8th-15th. QSLs via MØURX's OQRS
and LoTW.
-[425DXN # 1791 August 30, 2025] (1003-1017)
PYØS,
ST. PETER & ST. PAUL ROCKS. Ops KO8SCA, PY2XB,
AA7JV, KN4EEI,
PY5CC, and HA7RY activate St. Peter and St. Paul Rocks (SA-014) during
October and November. The actual dates will be announced later. They
will deploy Radios in Boxes (RIB) on the island and use them from
aboard a vessel. For their actual callsign and other updated
information see: http://py0s2025.com.
-[DXNL # 2478 October 1, 2025] (1003-1024)
S7, SEYCHELLES.
Kasimir, DL2SBY will be active as S79/DL2SBY
from the Seychelles from September
28th to October 12th.
He will be QRV on the HF bands with verticals and an inverted vee, and
on 6 meters with 5-element Yagi. QSOs will be uploaded to ClubLog. QSL
via LoTW, or direct to DL2SBY.
-[425DXN # 1794 September 20, 2025] (0926-1017)
SM, SWEDEN.
Eight special callsigns (7S1ØØSSA,
8S1ØØSSA, SB1ØØSSA, SC1ØØSSA, SD1ØØSSA, SE1ØØSSA, SF1ØØSSA and SM1ØØSSA) will be in
use from September
10th to October 12th
in celebration on the 100th anniversary of the Foreningen Sveriges
Sandareamatorer (SSA), Sweden's IARU member society. Look for activity
on 160-6 meters CW, SSB and digital modes. Details of the award program
will be published on https://hamaward.cloud/awards.
-[425DXN # 1791 August 30, 2025] (0905-1017)
TG,
GUATEMALA. Dwight, VE7BV will be QRV as TG9BBV from October 5th to
25th. Activity will be on 40 to 6 meters using CW, SSB,
and possibly
FT8. QSL via LoTW.
-[ARRL DX Bulletin # 40 October 2, 2025] (1003-1024)
V5, NAMIBIA.
Wolfgang, DH3WO, is presently operating as V51WO from Outjo,
350km north of Windhoek, mostly on FT8. QSL via DL3DXX, ClubLog's OQRS,
LoTW.
-[DXNL # 2479 October 8, 2025] (1010-1024)
VE, CANADA.
Watch for Mike, VE2XB, operating as VYØZOO
from Coral Harbor on Southampton Island (NA-007), Nunavut until December 18th,
QRV mostly on 40m CW. QSL via VE2XB.
-[DXNL # 2476 September 17, 2025] (0919-1017)
VP2M, MONTSERRAT.
Franco, J88BTI, moved to Montserrat (NA-103) in mid-September and is
now active as VP2MAA
on 40-6m (CW, SSB, FT8). He hopes to set up better antennas and
integrate an amplifier into his setup by the end of the year. QRV until September 2026.
QSL via IK2DUW.
-[DXNL # 2479 October 8, 2025] (1010-1031)
VU, INDIA.
Special callsign AT25GOA
celebrates HamFest India 2025. Look for activity from September 29th to October 13th
on 80-10 meters SSB, CW and FT8/FT4. See https://www.qrz.com/db/AT25GOA
for more information. QSOs will be uploaded to QRZ Logbook and ClubLog.
-[425DXN # 1796 October 4, 2025] (1003-1017)
XE, MEXICO.
A group of Mexican operators will be operating with a rare prefix as 6J8A from October 10th to 12th.
QSL via qrz.com.
-[DXNL # 2479 October 8, 2025] (1010-1017)
XT,
BURKINA FASO. Harald, DF2WO will be active again as XT2AW from Burkina
Faso on October
4th-27th. Usually he operates CW, SSB and FT8/FT4 on
various bands, 6 meters included, and via QO-100. QSL via MØOXO's OQRS
and LoTW.
-[425DXN # 1795 September 27, 2025] (1003-1031)
ZL7, CHATHAM IS.
Holger, ZL3IO, will be QRV as ZL7IO
(OC-038, until
October 16th. Activity is on 80m. QSL via LoTW.
-[ARRL DX Bulletin # 41 October 9, 2025] (1010-1017)
Propagation (Updated daily)
The Weekly Solar Data chart plots Solar Flux Index (SFI), Sunspot number (SSN) and Planetary K-Index (Kp) for the past 8 days. With 8 Planetary K-index readings each day, only the minimum, average and maximum K-index values are plotted. Note: You may click here or on the chart above to see the same data for the past month.
The Daily Solar Flux Index, Sunspot number, Planetary
K-index,
Solar Flux predictions and Solar Flare data used in this bulletin have
been collected by
KØCF from the U.S. Department of Commerce's NOAA
Space Weather Prediction Center.
The propagation graphs above are the creations of KØCF and are unique
in space weather reporting.
Please Note: The graphs are high resolution .PNG files which you may view in greater detail using your browser's "zoom" feature. Alternatively, right click on the graph and select "Open Image in New Tab" to enlarge it, or "Save Image As..." to save it to your computer for further analysis.
|
NASA's current view of the Sun at a wave- length of 131 Angstroms. This wavelength shows incredible solar detail. Click here or on the image to view as a full screen 48-hour video loop. It is fascinating! |
 |
Propagation
Summary
For the 8 day period from Wednesday, October 8th through yesterday, October 15th.
The average solar flux was 139, down 8 points from the previous week,
with a weekly high of 162 on Wednesday, October 15th, following
a low of 120 on October 8th.
The average sunspot count was 105, down by 21 from last week,
peaking at 125 on Sunday, October 12th after a
weekly low of 67 on October 8th.
The Planetary K-index weekly average was 3.8 with a
maximum of 5.3 on Sunday, October 12th, indicating
a minor geomagnetic storm. Yesterday's K-index maximum was 3.7 with generally quiet conditions.
Solar flare activity since October 9th has been high with 12
major flares, the largest of which was an M 4.8 event on Wednesday,
October 15th.
Propagation
Data
Major solar flares, Thursday, October 9th through 1354 UTC, October 16th.
| # | Date | UTC | Mag. |
|---|---|---|---|
| 1 | Oct 16 | 0021 | M 1.1 |
| 2 | Oct 15 | 2228 | M 2.7 |
| 3 | Oct 15 | 1410 | M 1.1 |
| 4 | Oct 15 | 0718 | M 3.7 |
| 5 | Oct 15 | 0415 | M 4.8 |
| 6 | Oct 14 | 2036 | M 3.1 |
| 7 | Oct 14 | 1247 | M 2.0 |
| 8 | Oct 14 | 0041 | M 2.0 |
| 9 | Oct 13 | 1318 | M 1.2 |
| 10 | Oct 13 | 0919 | M 2.7 |
| 11 | Oct 13 | 0526 | M 1.9 |
| 12 | Oct 09 | 1231 | M 2.0 |
(NOAA's graph of recent flare activity: GOES-X-Ray-Flux)
From the NOAA Space Weather Prediction
Center,
here are the probabilities of major solar flares and the predicted 10.7
cm Solar Flux for the next 3 days. NOAA updates this information daily.
| Date | M-Flares | X-Flares | Solar Flux |
|---|---|---|---|
| Oct 16 | 60% | 15% | 160 |
| Oct 17 | 60% | 15% | 160 |
| Oct 18 | 60% | 15% | 165 |
Looking farther ahead, here is the NOAA Space Weather Prediction Center forecast of 10.7 cm radio flux and maximum Planetary K-index (Kp) for the next 12 days. This data is updated by NOAA every Monday (last updated on October 13, 2025).
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Multiple CMEs Could Spark Auroras Tonight
All week long, active sunspot 4246 has been puffing CMEs toward
Earth--at least three of them. Although the CMEs are individually faint
and relatively slow, they could combine to cause a G2-class geomagnetic storm when they arrive on Oct. 16th. If such a storm materializes, auroras could descend into a dozen or more northern-tier US states.
(Copyright © SpaceWeather.com October 16, 2025.
Republished by
permission.)
Global
D Region Absorption
Conditions in the D-region of the ionosphere
have a dramatic effect on HF communications. The D-Region Absorption
map combines the effects of solar particles and
photons. Yellow to red colors on the map depict increasing signal
attenuation, where the bar chart at the right displays attenuation
versus frequency. Click the
thumbnail below for an animated map of D-Region Absorption:
The Aurora
Borealis
The aurora is not only beautiful to see but can have a
profound impact on HF and VHF radio propagation. For the HF operator,
auroras can result in a complete shut-down of propagation. However, on
VHF, auroras present interesting DX possibilities. Beam antennas are
very desirable and should be pointed north, towards the aurora. Signals
are reflected by “back-scatter” and will be distorted with a rough
buzz. SSB is the best voice mode to use, but copy can be difficult. CW
will have a rough buzzy sound but be perfectly copyable. Click the
thumbnail below for an animated map of aurora versus time:
Highs
for Cycle 25
Solar Flux: 336 on
August 8, 2024.
Sunspots: 382 on August
10, 2024.
Popular
Propagation web sites
https://prop.kc2g.com/
(Excellent Maximum Usable Frequency map)
NOAA https://www.swpc.noaa.gov/
https://www.spaceweather.com/
https://www.solarham.com/
https://dx.qsl.net/propagation/
A Propagation
Tutorial
The solar X-ray flux tracks solar activity and solar flares.
Solar
flux, which can vary from as low as 50 to as high as 300, influences
the level of ionization in the F2 region of the ionosphere, providing a
very good prediction of HF DX conditions. The higher the solar flux,
the better conditions will be for the higher HF frequencies and even 6
meters. However, the levels need to be maintained for some days to
allow ionization in the F2 layer to build up. A solar flux of 150
results in good HF band conditions, while levels of 200 and up can
provide great conditions.
Large X-ray flares on the sun can
increase the ionization of the D layer of the ionosphere (a lower
layer) on the sunlit side of the Earth, greatly attenuating or blocking
HF radio transmissions for up to a half hour. Solar flares often
produce Coronal Mass Ejections (CMEs) which, if Earth directed, can
lead to geomagnetic storms. Some large flares are also accompanied by
strong radio bursts that may interfere with other radio frequencies and
cause problems for satellite communication and radio navigation (GPS).
The
Planetary K-index is a measure of the magnitude of geomagnetic storms
and is an excellent indicator of disturbances in the Earth's magnetic
field. A level of 1 or 2 represents quiet geomagnetic conditions; a
reading of 3 or 4 may cause some propagation deterioration; 5 and 6 are
minor to moderate geomagnetic storms; and 7 to 9 are strong, severe,
and extreme storm conditions. Strong geomagnetic storms can trigger
Auroral displays and cause HF radio blackouts. Higher geomagnetic
activity also has the adverse effect of lowering maximum usable
frequencies, much like lower solar flux does.
For
best conditions, the solar flux should be above 150 for a few days with
the K index below 2. When these conditions are met, some good DX is
likely!
(Compiled from information on NOAA.gov and other sources.)
Contest Calendar
Weekly Contests
| Contest | Start UTC | End | Web Site | |
|---|---|---|---|---|
| K1USN Slow Speed Test | Monday | 0000Z | 0100Z | Rules |
| ICWC Medium Speed Test | Monday | 1300Z | 1400Z | Rules |
| Monday | 1900Z | 2000Z | ||
| Tuesday | 0300Z | 0400Z | ||
| CWops Test (CWT) | Wednesday | 1300Z | 1400Z | Rules |
| Wednesday | 1900Z | 2000Z | ||
| Thursday | 0300Z | 0400Z | ||
| Thursday | 0700Z | 0800Z | ||
| Weekly RTTY Test | Friday | 0145Z | 0215Z | Rules |
| NCCC CW Sprint (NS) | Friday | 0230Z | 0300Z | Rules |
Sunday at 7:00 PM in the Central Daylight Saving Time zone, or
Sunday at 6:00 PM in the Central Standard Time zone.
Full Calendar
| Contest | Start | End | Web Site | ||
|---|---|---|---|---|---|
| QRP ARCI Fall QSO Party | Oct 11 | 0000Z | Oct 11 | 2359Z | Rules |
| Makrothen RTTY Contest | Oct 11 | 0000Z | Oct 12 | 1559Z | Rules |
| Nevada QSO Party | Oct 11 | 0300Z | Oct 12 | 2100Z | Rules |
| Oceania DX Contest, CW | Oct 11 | 0600Z | Oct 12 | 0600Z | Rules |
| Scandinavian Activity Contest, SSB | Oct 11 | 1200Z | Oct 12 | 1200Z | Rules |
| Arizona QSO Party | Oct 11 | 1500Z | Oct 12 | 0500Z | Rules |
| Pennsylvania QSO Party | Oct 11 | 1600Z | Oct 12 | 0400Z | Rules |
| Oct 12 | 1300Z | Oct 12 | 2200Z | ||
| South Dakota QSO Party | Oct 11 | 1800Z | Oct 12 | 1800Z | Rules |
| 10-10 Int. Fall Contest, CW | Oct 18 | 0001Z | Oct 19 | 2359Z | Rules |
| New York QSO Party | Oct 18 | 1400Z | Oct 19 | 0200Z | Rules |
| Worked All Germany Contest | Oct 18 | 1500Z | Oct 19 | 1459Z | Rules |
| Stew Perry Topband Challenge | Oct 18 | 1500Z | Oct 19 | 1500Z | Rules |
| Illinois QSO Party | Oct 19 | 1700Z | Oct 20 | 0100Z | Rules |
| ARRL School Club Roundup | Oct 20 | 1300Z | Oct 24 | 2359Z | Rules |
| CQ Worldwide DX Contest, SSB | Oct 25 | 0000Z | Oct 26 | 2400Z | Rules |
| ARRL Sweepstakes Contest, CW | Nov 1 | 2100Z | Nov 3 | 0300Z | Rules |
| WAE DX Contest, RTTY | Nov 8 | 0000Z | Nov 9 | 2359Z | Rules |
| 10-10 Int. Fall Contest, Digital | Nov 8 | 0001Z | Nov 9 | 2359Z | Rules |
| JIDX Phone Contest | Nov 8 | 0700Z | Nov 9 | 1300Z | Rules |
| OK/OM DX Contest, CW | Nov 8 | 1200Z | Nov 9 | 1200Z | Rules |
| ARRL Sweepstakes Contest, SSB | Nov 15 | 2100Z | Nov 17 | 0300Z | Rules |
| LZ DX Contest | Nov 22 | 1200Z | Nov 23 | 1200Z | Rules |
| North American SSB Sprint Contest | Nov 23 | 0000Z | Nov 23 | 0400Z | Rules |
| CQ Worldwide DX Contest, CW | Nov 29 | 0000Z | Nov 30 | 2400Z | Rules |
| ARRL 160-Meter Contest | Dec 5 | 2200Z | Dec 7 | 1600Z | Rules |
| ARRL 10-Meter Contest | Dec 13 | 0000Z | Dec 14 | 2359Z | Rules |
| ARRL Rookie Roundup, CW | Dec 21 | 1800Z | Dec 21 | 2359Z | Rules |
| RAC Winter Contest | Dec 27 | 0000Z | Dec 27 | 2359Z | Rules |
| Stew Perry Topband Challenge | Dec 27 | 1500Z | Dec 28 | 1500Z | Rules |
| RAEM Contest | Dec 28 | 0000Z | Dec 28 | 1159Z | Rules |
| ARRL Kids Day | Jan 3 | 1800Z | Jan 3 | 2359Z | Rules |
| ARRL RTTY Roundup | Jan 3 | 1800Z | Jan 4 | 2400Z | Rules |
| North American QSO Party, CW | Jan 10 | 1800Z | Jan 11 | 0600Z | Rules |