The
Eastern Iowa DX Bulletin
Number
306, December 26, 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 (The online archive is no
longer updated.)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
3A, MONACO. Col, MMØNDX and Steve, MMØSAJ will be active again as 3A/MMØNDX and 3A/MMØSAJ from Monte Carlo, Monaco from December 30th to January 3rd. Their main focus will be on the low bands using SSB, FT8/FT4 and RTTY. QSL both calls via EB7DX and LoTW.
-[425DXN # 1807 December 20, 2025] (1226-0109)
4J,4K, AZERBAIJAN. A group of operators will be QRV from Shahdagh National Park (POTA AZ-0006) as 4KØT from December 29th to 31st, mostly on 17m. QSL via LoTW.
-[DXNL # 2490 December 24, 2025] (1226-0102)
4J,4K, AZERBAIJAN. Jan, DL4XT will be active holiday style as 4K/DL4XT from Azerbaijan from December 26th to January 3rd. He will operate SSB, CW and FT8 on 40 and 20-10 meters. QSL via LoTW, ClubLog's OQRS and QRZ.
-[425DXN # 1806 December 13, 2025] (1226-0102)
4X, ISRAEL.
A Christmas 2025 operation will be conducted from Israel on December 25th-31st.
Four groups of operators capable of providing QSOs in FT8, SSB, CW and
via satellite will be QRV as 4X25X,
4X25M, 4X25A and 4X25S. For more
information, see: https://www.iarc.org/xmas-2025/.
QSL via 4X6ZM, bureau
or direct.
-[425DXN # 1807 December 20, 2025] (1219-0102)
5R,
MADAGASCAR. Eric, F6ICX, is QRV as 5R8IC from
Sainte-Marie Island
(AF-090) until the
end of December. Activity is on the HF bands using
CW, SSB, FT8, FT4, and Satellite QO-100. QSL to F6ICX.
-[ARRL DX Bulletin # 49 December 4, 2025] (1205-0102)
6Y, JAMAICA.
Lester, W8YCM, is QRV as both W8YCM/6Y
and 6Y8LV until mid-January 2026.
Activity is holiday style on 17, 12, and 10 meters using SSB. QSL
direct to W8YCM.
-[ARRL DX Bulletin # 50 December 11, 2025] (1212-0116)
9A,
CROATIA. Special event station 9A169TESLA is QRV until December 31st
to
celebrate Nikola Tesla's birthday. QSL via operators' instructions.
-[ARRL DX Bulletin # 49 December 4, 2025] (1205-0102)
9Y, TRINIDAD
& TOBAGO. Earl, WA3DX will be active as 9Y9DX from Arouca,
Trinidad (SA-011) on December
17th-29th. He will operate mainly FT8 and FT4 on 40-10
meters. QSOs will be uploaded to ClubLog. QSL via LoTW, or direct to WA3DX.
-[425DXN # 1805 December 6, 2025] (1212-0102)
C5,
THE GAMBIA. Andre, ON7YK, is QRV as C5YK from Kotu until January 25th.
Activity is on 20 to 10 meters using SSB, RTTY, FT8, FT4, and some CW.
QSL via LoTW.
-[ARRL DX Bulletin # 49 December 4, 2025] (1205-0123)
CE9, ANTARCTICA.
Oleg, ZS1ANF, has returned to Wichaway (WAP MNB-11) and operates as ZS7ANF on 17, 15,
and 10m CW. QSL via RK1PWA.
-[DXNL # 2489 December 17, 2025] (1219-0109)
CE9, ANTARCTICA.
Alex, UG1A, operating as RI1ANI, is expected
to leave Novolazarevskaya Station on December 1st, and head to Progress
station. From December
5th onwards, he will take part in the traverse from
Progress to Vostok Station, where he will stay for approximately 40
days. QSL via ClubLog's OQRS,
or via RN1ON.
-[425DXN # 1805 December 6, 2025] (1205-0102)
CN, MOROCCO.
Members of the Association Royale des Radioamateurs du Maroc will be
active as CN35CAN
during the 35th edition of the Africa Cup of Nations, the biennial
international competition for African football (soccer) teams. Morocco
will host the tournament from December
21st to January 18th. QSL direct to CN35CAN.
-[425DXN # 1806 December 13, 2025] (1219-0123)
CT, PORTUGAL.
To celebrate the 100th anniversary of Rede dos Emissores Portugueses
(REP), Portugal's IARU member society, around fifty operators scattered
all around the country will use three special callsigns - CS26REP, CR26REP and CR3REP on January 1st-7th. Look for activity on various bands and modes, and via QO-100. Certificates and eQSLs will be available on https://hamaward.cloud/awards.
-[425DXN # 1807 December 20, 2025] (1226-0109)
D4, CAPE VERDE.
Beni, HB9HNT, is QRV as D4NT
until January 1st.
Activity is on the HF bands. QSL to HB9HNT.
-[ARRL DX Bulletin # 51 December 18, 2025] (1219-0102)
DXCC TOP TWENTY.
Here are the top 20 entities on ClubLog’s "DXCC Most Wanted" list as of
December 26, 2025:
1. P5 DPRK
(North Korea) 11.
KH4 Midway Island
2.
KH3 Johnston
Island 12.
VKØM Macquarie Island
3. KH7K Kure
Island
13. EZ Turkmenistan
4. CEØX San Felix
Islands 14.
KP5 Desecheo Island
5. FT5/X Kerguelen
Island 15.
PYØS Saint Peter And Paul Rocks
6. BS7H Scarborough
Reef 16.
VPØS South Sandwich Islands
7. BV9P Pratas
Island 17.
YK Syria
8. YVØ Aves
Island
18. ZL9 New Zealand Subantarctic
Islands
9. 3Y/P Peter 1
Island 19.
VKØH Heard Island
10. 3Y/B Bouvet
Island 20.
FT/T Tromelin Island
For the complete list, see
https://clublog.org/mostwanted.php
-[KØCF December 26, 2025 (1226-0116)
EA, SPAIN.
The radio club in Palencia uses the callsign EG1SANTA until the end of the year.
QSL via EC1R.
-[DXNL # 2489 December 17, 2025] (1219-0102)
EA, SPAIN.
Celebrating Christmas and the New Year from the city of Vigo, EG1NV
will be active from December
2nd to January 12th. See
https://www.qrz.com/db/EG1NV
for more information. QSL via LoTW, eQSL,
and QRZ Logbook.
-[425DXN # 1804 November 29, 2025] (1128-0109)
F, FRANCE.
Dominique, F4JMX is going to put the callsign TM63SC on the air
from December 17th
to 31st. It was used in previous years by F8DZU
(Jean-Pierre), who became silent key earlier this year.
-[DXNL # 2489 December 17, 2025] (1219-0102)
FY, FRENCH
GUIANA. Pierre-Jean, F4GPK will be active again as TO2FY from Korou,
French Guiana from December
22nd to January 15th.
Activity will be mostly on 20, 15, and 10 meters using SSB only. He
does not do paper QSLs or ClubLog. QSL only via LoTW and eQSL.
-[425DXN # 1806 December 13, 2025] (1219-0116)
G, ENGLAND. Members of the Humber Fortress DX Amateur Radio Club operate as GB26HNY from December 26th to January 18th.
-[DXNL # 2490 December 24, 2025] (1226-0116)
HA, HUNGARY.
The first official, regular radio broadcast in Hungary began on
December 1, 1925, which is now celebrated as Hungarian Radio Day. To
mark that centenary, the Hungarian Radio Amateur Society (MRASZ) and
the Honfy Jozsef Radioclub (HA1KHJ) organize a commemorative activity
to be held from November
15th to December 31st under nine special callsigns: HG1ØØRADIO, HG1ØØYHRB, HG1ØØAN, HG1ØØEG, HG1ØØFO, HG1ØØIT, HG1ØØRC, HG1ØØSD and HG1ØØUD. Look for
activity on 160-10m CW, SSB & digital modes, and via QO-100. A
certificate will be available: https://mrasz.org/100-years-of-hungarian-broadcasting-award.
-[425DXN # 1802 November 15, 2025] (1114-0102)
HB,
SWITZERLAND. Club HB9IPA continues to celebrate their
club's 70th
anniversary with the special callsign HB7ØIPA until the end of 2025
on
HF and via QO-100.
-[DXNL # 2487 December 3, 2025] (1205-0102)
HK, COLOMBIA and
HKØ, SAN ANDRES & PROVIDENCIA. Christoph, DF3TJ is active from Colombia as HK4/DF3TJ until sometime in January. "There will also be activations of HKØ/DF3TJ from San Andres (NA-033) and Providencia (NA-049) on short term notice", he says. QSL via ON5JC.
-[425DXN # 1808 December 27, 2025] (1226-0116)
HS,
THAILAND. Special event callsign HS25SG will be
activated on December
1st-30th to celebrate the 33rd Southeast Asian Games and
as part of the
"SatFinder" educational campaign, which promotes space, satellite, and
radio science to students and the general public through amateur radio
activities. See https://www.qrz.com/db/HS25SG
for more information. QSL
via ClubLog's OQRS,
LoTW, and QRZ Logbook.
-[425DXN # 1804 November 29, 2025] (1128-0102)
I, ITALY.
ARI section Gorizia remains active as II3GONG until December 29th.
-[DXNL # 2489 December 17, 2025] (1219-0102)
J3, GRENADA. Rikk, WE9G will be active as J38WG from Grenada (NA-024) on January 1st-16th.
This will be a SO2R (Single Operator 2 Radios) activity on 160-6
meters, mostly FT8 with some CW and SSB. "I might also do some POTA",
he says. QSL via ClubLog's OQRS, LoTW, or via WE9G.
-[425DXN # 1808 December 27, 2025] (1226-0116)
JA, JAPAN.
Take, JI3DST will be active as JS6RRR
from Miyako Island (AS-079) from December 11th until April 17th.
He will operate SSB, CW and FT8 on 40-6m. Other callsigns to be used
are JI3DST/6,
JJ5RBH/6, JI3DST/p and JJ5RBH/p. QSOs will
be uploaded to ClubLog and LoTW.
-[425DXN # 1805 December 6, 2025] (1205-0102)
KHØ, MARIANA IS. Ken, JO1VRK expects to be active as KHØ/AJ6VJ from Saipan (OC-086), Mariana Islands from December 29th to January 3rd. He will be QRV on 40-10 meters CW and digital modes. QSL via LOTW, eQSL, and ClubLog's OQRS.
-[425DXN # 1807 December 20, 2025] (1226-0109)
KP5, DESECHEO I. The Vieques Island Amateur Radio Club (NP3VI) and the Manyana DX Foundation will sponsor the KP5/NP3VI DXpedition to Desecheo Island, now number 14 on the DXCC Top Twenty list.
Plans are to deploy two self-sustained remote deployable stations between January 12th and 14th. The DXpedition is expected to operate continually for 30 days.
(Full details will be published in the January 9th edition of the Eastern Iowa DX Bulletin. Stay tuned!)
-[425DXN # 1808 December 27, 2025] (1226-0109)
LZ, BULGARIA. Special callsigns LZ2Ø25ZONE and LZ2Ø26EURO celebrate Bulgaria's admission into the Eurozone and adoption of the Euro as of January 1st. Also look for LZ1EURO to be active on January 1st-6th. QSL LZ2Ø25ZONE and LZ2Ø26EURO via LZ2VP and LZ1EURO via LZ3SCO.
-[425DXN # 1807 December 20, 2025] (1226-0109)
LZ, BULGARIA. The special event callsign LZ1KOLED will be active from December 24th to 29th. Then, from January 1st to 6th, the operators continue as LZ1EURO to mark Bulgaria's entry into the Euro currency zone.
-[DXNL # 2490 December 24, 2025] (1226-0109)
OA,
PERU. The Peruvian Radio Club celebrates its 95th
anniversary with the
callsign 4T95O
during December.
QRV on 40-10 meters, as well as on 6m,
2m and 70cm, CW, SSB, RTTY, FM, and FT8. For QSL information (including
a downloadable eQSL) see: https://www.oa4o.pe
-[DXNL # 2486 November 26, 2025] (1128-0102)
OE, AUSTRIA.
Special callsign OEØYOTA
is going to take part in the December
YOTA Month 2025 events.
-[DXNL # 2486 November 26, 2025] (1128-0102)
ON, BELGIUM.
Commemorating the 81st anniversary of the Battle of the Bulge during
World War II, members of UBA Section Bruxelles-Est (ON5UB) will be
active as OR81NUTS
from December 13th
to 31st.
The suffix of the special callsign is General Anthony C. McAuliffe's
famous single-word reply in response to a surrender ultimatum.
-[425DXN # 1805 December 6, 2025] (1205-0102)
OX, GREENLAND. Michael, OX3MC, plans to get on the air whenever time permits from December 29th to February 25th from Pituffik Space Base (NA-018). QRV on 80-10m, mostly on SSB. QSL via OZ QSL bureau.
-[DXNL # 2490 December 24, 2025] (1226-0227)
PA, NETHERLANDS.
Special callsigns celebrating Christmas and the New
Year from the Netherlands include:
PA25SANTA
Dec 1 -
Jan 1 QSL via PA1AW
PA25XMAS
Dec
1-31
no QSL, certificate on QRZ
PD25STAR
Dec
1-31
no QSL, certificate on QRZ
PD26HNY
Dec 1 - Jan 31 no QSL, certificate on QRZ
PF25XMAS
Dec
1-31
QSL via PC1K;
certificate on QRZ
PH25XMAS
Dec
6-28
no QSL, certificate on https://award.pa3efr.nl
PH26HNY
Dec 28 - Jan 5 no QSL, certificate on https://award.pa3efr.nl
PI25XMAS
Dec
1-31
no QSL, certificate on QRZ
More
information can be found on https://www.qrz.com/db/PD25XMAS.
-[425DXN # 1804 November 29, 2025] (1128-0102)
PZ, SURINAME.
Joe, OZØJ will be active as PZ5OZ
from PZ5RA's rental shack at Lelydorp, Suriname from December 21st to January 2nd.
He will operate CW, SSB, FT8 (F/H) and possibly RTTY on 160-6 meters.
Note: Do NOT mail direct cards to OZØJ, as the Danish postal operator
will discontinue letter delivery service on December 30. See https://pz5oz.oz0j.dk
for more information. QSL via ClubLog's OQRS
(preferred), LoTW, and eQSL.
-[425DXN # 1805 December 6, 2025] (1219-0102)
SM,
SWEDEN. Radio club SK3GK is QRV with special callsign SM1ØØXF until
December 31st to mark the first radio broadcast 100 years
ago from
Gaevle. QSL via bureau.
-[ARRL DX Bulletin # 49 December 4, 2025] (1205-0102)
SP, POLAND.
The Dobrzycki Amateur Radio Club (SP3PDO) will use twelve special
callsigns during 2026 to honor as many different Polish saints. The
first callsign in the series, SP1894MMK (January 1st-31st), is for St. Maximilian Maria Kolbe (SP3RN), born on January 8, 1894, and killed at Auschwitz in 1941. It will be followed by SP144ØSL (February), SP1Ø4ØSSZ (March), SP1865JML (April), SP192ØKW (May), SP1373JA (June), SP1183JO (July), SP19Ø5MFK (August), SP1373AB (September), SP155ØSK (October), SP1234KK (November) and SP1835JK (December). See https://radioawards.club/ses/155 for the certificates. QSL via SP3PDO.
-[425DXN # 1807 December 20, 2025] (1226-0123)
SV, GREECE.
Tom, OE4EIE operates as SV/OE4EIE
from December 21st
until January 4th.
-[DXNL # 2489 December 17, 2025] (1219-0109)
TA,
TURKEY. Special event callsign TC25YOTA, staffed by
youngsters, will be
active throughout
December. See also: https://events.ham-yota.com.
QSL
via ClubLog's OQRS.
-[DXNL # 2487 December 3, 2025] (1205-0102)
TG,
GUATEMALA. Todd, AF4CZ, will be active holiday style as TG9/AF4CZ from
Guatemala from December
7th to January 5th. He will operate mainly
FT8/FT4 on 40-10 meters. QSOs will be uploaded to LoTW, eQSL and
ClubLog.
-[425DXN # 1804 November 29, 2025] (1205-0109)
TL, CENTRAL
AFRICA. Joao, CR7BNW will be active as TL8BNW from Bangui,
Central African Republic for
six months.
During his stay he will be QRV on 40, 20, 15, and 10 meter SSB and FT8.
He has already conducted some preliminary tests in preparation for his
first activity, which is scheduled for December 20th-25th.
QSL via LoTW, and QRZ.
-[425DXN # 1807 December 20, 2025] (1219-0123)
UA, EUROPEAN RUSSIA. Special callsigns R2Ø26A, R2Ø26C, R2Ø26L, R2Ø26N, R2Ø26NY, R2Ø26S, R2Ø26X, UE26HNY and UE26NY will be active from December 29th to January 11th for the annual "Russian New Year" radio marathon organized by the Miller DX Club (https://mdxc.ru/) and the Rostov Oblast branch of the Russian Amateur Radio Union (SSR). See https://hamlog.online/club/mdxc for the certificates. QSL via RQ7L.
-[425DXN # 1806 December 13, 2025] (1226-0116)
VP5, TURKS
& CAICOS. Mark, AA2MA will be QRV as VP5/AA2MA from
Caicos Island (NA-002) during
December. Activity will be on his free time on 40, 20, and
10 meters using CW or FT8. QSL via AA2MA.
-[ARRL DX Bulletin # 51 December 18, 2025] (1219-0102)
VP8/H,LU,CE9,HFØ,4K1, SOUTH SHETLAND IS.
Ivo, LZ1AAW is heading to the Bulgarian Antarctic Base St. Kliment
Ohridski on Livingston Island (AN-010). He plans to be QRV as LZØA in his spare time from approximately December 27th to February 16th.
He will operate SSB and FT8/FT4 on 20 meters and possibly other bands.
QSOs will be uploaded to LoTW after the end of the activity. QSL via LZ2UU.
-[425DXN # 1807 December 20, 2025] (1226-0213)
VU, INDIA. Bernhard, DL2GAC, is on the air as VU2BMS until mid-January.
-[DXNL # 2490 December 24, 2025] (1226-0116)
XF4, REVILLAGIGEDO. Following his brief October visit to Socorro Island, Revillagigedo, Mark (XE1B) returns to activate XF4B for a Christmas holiday operation. Accompanied by Guillermo (XE1IMO), he was scheduled to arrive on December 23rd, with the activation running through December 31st.
The team is deploying two radios, one linear amplifier, and four
antennas, allowing for simultaneous SSB and FT8 operations on 80-6
meters. All FT8 contacts (excluding 60m) will use Superfox mode with
call validation to prevent pirate stations. Efforts are ongoing to
prepare for a more extensive activation planned for 2026. QSOs will be
uploaded to LoTW as OQRS requests are processed. QSL via ClubLog's OQRS only.
-[425DXN # 1808 December 27, 2025] (1226-0103)
XU, CAMBODIA.
Tom, DL7BO, will be QRV as XU7GNY
from December 22nd
to January 18th. Activity will be on 160 through 6 meters
using CW, SSB, and FT8, and concentrating on the lower bands. QSL
direct via DJ4WK.
-[ARRL DX Bulletin # 51 December 18, 2025] (1219-0123)
YO,
ROMANIA. Members of the YO3KRM Radioclub will run a
Christmas Special
Event on December 5th-31st, with three special callsigns: YOØHOHO,
YOØXMAS, and
YRØUDOLPH.
QSL via YO3GND.
Certificates will be available,
see YOØHOHO for
the details.
-[425DXN # 1804 November 29, 2025] (1205-0102)
YU, SERBIA.
Special call signs YT25YOTA
and YU25YOTA
are active throughout
December in celebration of IARU Region 1 Young Radio
Operators Month. QSL via operators' instructions.
-[ARRL DX Bulletin # 51 December 18, 2025] (1219-0102)
Z8, SOUTH SUDAN.
Diya, YI1DZ, will be QRV as Z81D
from Juba from December
14th to March 10th. Activity will be in his spare time.
QSL to YI1DZ.
-[ARRL DX Bulletin # 50 December 11, 2025] (1212-0116)
ZA, ALBANIA. Pete, ZL4TE, signs ZA/ZL4TE from Albania from December 28th to 30th. After that he travels on to Austria, Germany, Hungary, England but has not decided yet about getting on the air.
-[DXNL # 2488 December 10, 2025] (1226-0102)
ZA, ALBANIA.
Tom, OE4EIE operates as ZA/OE4EIE
on December 19th and
20th, and again from January 4th to 6th.
QSL to OE4EIE.
-[DXNL # 2489 December 17, 2025] (1219-0109)
ZL,
NEW ZEALAND. Special callsign ZL6ØPAH will be used
by Phil, ZL3PAH from
November 23rd to
February 22, 2026, to celebrate his diamond jubilee in
amateur radio. He will operate CW, RTTY, and "maybe a little SSB too"
on 80-10 meters. QSL via LoTW.
-[425DXN # 1802 November 15, 2025] (1121-0220)
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! |
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Propagation
Summary
For the 8 day period from Thursday, December 18th through yesterday,
December 25th.
The average solar flux was 133, up 13 points from the previous week,
with a weekly high of 163 on Thursday, December 25th, following
a low of 116 on December 18th.
The average sunspot count was 85, up 1 from last week,
peaking at 113 on Thursday, December 25th after a
weekly low of 33 on December 19th.
The Planetary K-index weekly average was 3.9 with a
maximum of 5.0 on Monday, December 22nd, indicating
a minor geomagnetic storm. Yesterday's K-index maximum was 3.3 with
generally quiet conditions.
Solar flare activity since December 19th has been low with 3
major flares, the largest of which was an M 1.3 event on Sunday,
December 21st.
Propagation
Data
Major solar flares, Friday, December 19th through 1429 UTC, December
26th.
| # | Date | UTC | Mag. |
|---|---|---|---|
| 1 | Dec 21 | 1827 | M 1.3 |
| 2 | Dec 20 | 0753 | M 1.0 |
| 3 | Dec 19 | 1558 | M 1.0 |
(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 |
|---|---|---|---|
| Dec 26 | 45% | 5% | 165 |
| Dec 27 | 45% | 5% | 170 |
| Dec 28 | 45% | 5% | 175 |
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 December 22, 2025).
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|
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An
X-Flare For Christmas?
Growing rapidly in the sun's southern hemisphere, new
sunspot 4321 has an unstable 'beta-gamma-delta' magnetic
field. This means it is dangerous. The sunspot poses a threat for
Earth-directed X-flares on
Christmas Day.
(Copyright © SpaceWeather.com December 25, 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 | ||
|---|---|---|---|---|---|
| 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 |
| North American QSO Party, SSB | Jan 17 | 1800Z | Jan 18 | 0600Z | Rules |
| ARRL January VHF Contest | Jan 17 | 1900Z | Jan 19 | 0359Z | Rules |
| CQ 160-Meter Contest, CW | Jan 23 | 2200Z | Jan 25 | 2159Z | Rules |
| REF Contest, CW | Jan 24 | 0600Z | Jan 25 | 1800Z | Rules |
| Vermont QSO Party | Feb 7 | 0000Z | Feb 8 | 2400Z | Rules |
| 10-10 Int. Winter Contest, SSB | Feb 7 | 0001Z | Feb 8 | 2359Z | Rules |
| Mexico RTTY International Contest | Feb 7 | 1200Z | Feb 8 | 2359Z | Rules |
| Minnesota QSO Party | Feb 7 | 1400Z | Feb 7 | 2400Z | Rules |
| British Columbia QSO Party | Feb 7 | 1600Z | Feb 8 | 2400Z | Rules |
| North American Sprint, CW | Feb 8 | 0000Z | Feb 8 | 0359Z | Rules |
| ARRL School Club Roundup | Feb 9 | 1300Z | Feb 13 | 2359Z | Rules |
| CQ WW RTTY WPX Contest | Feb 14 | 0000Z | Feb 15 | 2400Z | Rules |
| CQ 160-Meter Contest, SSB | Feb 20 | 2200Z | Feb 22 | 2159Z | Rules |
| ARRL Inter. DX Contest, CW | Feb 21 | 0000Z | Feb 22 | 2400Z | Rules |
| REF Contest, SSB | Feb 21 | 0600Z | Feb 22 | 1800Z | Rules |
| South Carolina QSO Party | Feb 21 | 1500Z | Feb 22 | 0159Z | Rules |
| North American QSO Party, RTTY | Feb 28 | 1800Z | Mar 1 | 0600Z | Rules |
| ARRL Inter. DX Contest, SSB | Mar 7 | 0000Z | Mar 8 | 2400Z | Rules |
| Oklahoma QSO Party | Mar 14 | 1400Z | Mar 15 | 2100Z | Rules |
| Stew Perry Topband Challenge | Mar 14 | 1500Z | Mar 15 | 1500Z | Rules |
| Idaho QSO Party | Mar 14 | 1900Z | Mar 15 | 1900Z | Rules |
| North American Sprint, RTTY | Mar 15 | 0000Z | Mar 15 | 0359Z | Rules |
| Wisconsin QSO Party | Mar 15 | 1800Z | Mar 16 | 0100Z | Rules |
| BARTG HF RTTY Contest | Mar 21 | 0200Z | Mar 23 | 0200Z | Rules |
| Russian DX Contest | Mar 21 | 1200Z | Mar 22 | 1200Z | Rules |
| Virginia QSO Party | Mar 21 | 1400Z | Mar 22 | 2400Z | Rules |
| CQ WW WPX Contest, SSB | Mar 28 | 0000Z | Mar 29 | 2400Z | Rules |