F4JDM — FT8 activity observed at SO8OO

DXCC entity inferred from callsign: France Most frequent locator attributed to this token: JN07

Receiver-side FT8 activity involving F4JDM, decoded by SO8OO in southeastern Poland. 279 FT8 messages attributed to this token as transmitter, on 40m, 20m, 10m, across 7 UTC dates in the available aggregate history. Observed between 2026-06-19 and 2026-09-12.

These are automated observations at the SO8OO receiver, not an official contact log. Times are UTC. Attribution follows decoded FT8 message structure: CQ uses the first token and directed-looking messages use the second. Free text that resembles a directed message can be attributed imperfectly. Summary S/N reflects propagation plus SO8OO receiver, antenna and local-noise conditions. Counts are not adjusted for monitoring outages; transmissions that were not decoded are absent. Inferred entity and location data may be inaccurate for portable, remote or special-event operation.

SO8OO decoded 279 FT8 messages attributed to F4JDM as the transmitting token by decoded message structure across 7 UTC dates in the available aggregate history. The largest monitored-band total was 40 m (75%), followed by 20 m (24%) and 10 m (1%). Several six-hour UTC windows tied for the largest share (99%), so no unique busiest interval is claimed. Most successfully decoded messages attributed to this token fell in SO8OO's strong S/N range (95%); the estimated median was -1 dB.

Overview

279

Messages attributed

UTC dates decoded

Active 15-min windows

-1 dB

Estimated median S/N

Bands

40m · 210 20m · 66 10m · 3

First attributed message: 2026-06-19
Last attributed message: 2026-09-12 21:18 UTC

Observed FT8 message patterns

Attributed sample: 279 messages
Active dates: 7 UTC dates
Estimated median S/N: -1 dB
Estimated 10th-90th percentile: -7 to +9 dB
Recurring-pattern threshold: Met

SO8OO display ranges among successful decodes: weak (≤ -16 dB) 1, moderate (-15 to -9 dB) 13, strong (≥ -8 dB) 265.

WSJT-X defines S/N reports against a 2,500 Hz reference noise bandwidth. The ranges above are SO8OO receiver-side display categories, not official WSJT-X classes, transmitter-power measurements or estimates of how easy the station is to hear elsewhere. Statistics include only successful decodes on SO8OO's monitored FT8 channels; transmissions that were not decoded are absent.

Frequent counterpart tokens observed at SO8OO

Tokens most often paired with F4JDM in decoded directed-looking exchanges:

A41ZZ · Oman A61QQ · United Arab Emirates BA4QFQ · China BD8ELZ · China BH2WTV · China HL2CFY · Republic of Korea JR5MJS · Japan OY5T · Faroe Islands UN8PC · Kazakhstan BA3QIQ · China BG0FQU · China CT7ARQ · Portugal

Attributed messages by UTC hour

Rolling 90-day UTC chart window. Counts follow decoded message structure: the first token for CQ, or the second token in a directed-looking message.

Most frequent locator attributed to F4JDM

The map compares the centres and boundaries of the locator field attributed to this token by decoded message structure, 2° × 1° as a Maidenhead square, and SO8OO's six-character receiver square. The separation is not an exact antenna-to-antenna distance or a radio-path length.

Attributed locator: JN07 · 128 decoded messages
SO8OO receiver locator: KN09VW
Locator-centre separation: 1,544 km (approx.)
Last such locator decoded: 2026-09-12 21:18 UTC

A decoded locator can describe portable, remote or special-event operation and is not proof of a permanent station address or transmitter identity.

Observed FT8 exchanges

S/N cells show: decoded at SO8OO / report transmitted by the counterpart. An observed exchange is not a QSL or an official logbook confirmation.

Time UTC	Band	F4JDM S/N	Counterpart	Counterpart S/N	Msgs	Capture
09-12 21:15	40m	+2 / -	DS5USH	- / -17	3	✓ Closing fragment
09-12 21:12	40m	+2 / -1	ON1DGN	-8 / -	4	✓ Full exchange observed
09-12 21:10	40m	-1 / -	BG2GWN	- / -	3	Partial capture
09-12 20:28	40m	+4 / -	M7GOA	- / -23	2	✓ Closing fragment
09-12 20:20	40m	-3 / -	JH0MXV	- / -	3	Partial capture
09-12 20:18	40m	+1 / -	UA4CKN	-4 / -17	2	✓ Closing observed
09-12 20:13	40m	-2 / -14	R3UDU	-13 / -9	6	✓ Full exchange observed
09-12 20:12	40m	-2 / -	R2FDP	- / -6	5	✓ Closing fragment
09-12 20:11	40m	+4 / +7	M9NTS	-14 / 0	3	Partial capture
09-11 21:22	40m	0 / -	HL3KPJ	- / -	3	Partial capture
09-11 21:16	40m	-2 / -	YL3NU	- / +1	2	✓ Closing fragment
09-11 21:16	40m	- / -	R3UDU	-14 / -	2	Partial capture
09-11 21:12	40m	-6 / +4	MW7RHR	-12 / +3	7	✓ Full exchange observed
09-11 21:07	40m	-7 / -	EA1AGM	-20 / -17	6	✓ Closing observed
09-11 21:02	40m	-6 / 0	DB4KBR	-4 / +8	4	✓ Full exchange observed
09-11 21:00	40m	- / -	MW7RHR	-13 / -	3	Partial capture
09-11 20:58	40m	-8 / -	UA2FFD	- / -3	2	✓ Closing fragment
09-11 20:54	40m	-3 / -	HL3KPJ	- / -	2	Partial capture
09-11 20:52	40m	-7 / -	VK5COL	- / -19	4	✓ Closing fragment
09-11 20:50	40m	-6 / -5	DL5FCE	-10 / -16	5	✓ Full exchange observed
09-11 20:47	40m	-4 / -	BA3QIQ	- / -16	5	✓ Closing fragment
09-11 20:45	40m	-6 / -	LB5WB	- / -11	2	✓ Closing fragment
09-11 20:44	40m	-4 / -	BG4OOO	- / -25	2	Partial capture
09-11 20:42	40m	0 / -	BA3QIQ	- / -15	3	Partial capture
09-11 20:37	40m	-4 / -	VJ6X	- / -14	5	✓ Closing fragment
09-11 20:36	40m	-2 / -	BG0FQU	- / -14	2	✓ Closing fragment
09-11 20:34	40m	0 / -	JF1UVJ	- / -15	3	✓ Closing fragment
09-11 20:32	40m	-1 / -	DC9GT	- / +6	2	✓ Closing fragment
09-11 20:29	40m	0 / 0	IK1MJK/P	-13 / -	4	✓ Full exchange observed
09-11 20:25	40m	+4 / -	UN7PPV	- / -16	2	✓ Closing fragment
09-11 20:23	40m	+3 / -	OE8PIT	- / -1	3	Partial capture
09-11 20:21	40m	+3 / -	CT7AXN	- / -	2	Partial capture
09-11 20:18	40m	+2 / -	HL3KPJ	- / -21	4	Partial capture
09-11 20:17	40m	+4 / -	DD5DD	- / -8	2	Partial capture
09-11 20:15	40m	+3 / -	VK7HOB	- / -	2	Partial capture
09-11 20:14	40m	+5 / -4	OE8DDX	+1 / -	5	✓ Full exchange observed
09-11 19:18	40m	+4 / -12	JA6MWW	-16 / -20	3	✓ Full exchange observed
09-11 19:16	40m	+5 / -	MW6IUT	- / -5	3	✓ Closing fragment
08-30 20:22	40m	-1 / -	SV1OML	- / -10	3	✓ Closing fragment
08-30 20:20	40m	0 / -	S57MG	- / -10	2	✓ Closing fragment
08-30 20:18	40m	0 / -	SP9KSK	- / -13	2	✓ Closing fragment
08-30 20:15	40m	-4 / -	DL9MY	- / -	2	✓ Closing fragment
08-30 20:13	40m	-2 / -	EA3ISZ	- / -11	2	✓ Closing fragment
08-30 20:10	40m	-3 / -7	DL9KM	-1 / -	4	✓ Closing observed
08-30 20:09	40m	-2 / -	PA3AGN	- / +8	4	✓ Closing fragment
08-30 20:07	40m	-4 / -	GI4OGS	-2 / -	5	✓ Full exchange observed
08-30 20:04	40m	-2 / -	EA3JEM	-11 / -2	3	✓ Full exchange observed
08-30 20:03	40m	-4 / -	DL6NAC	+2 / -11	3	✓ Closing observed
08-30 20:00	40m	-4 / -	M8JJS	- / -17	2	✓ Closing fragment
08-30 19:58	40m	-4 / -	EA7AZH	- / -15	2	✓ Closing fragment

Recent FT8 messages decoded at SO8OO

Frequency values are decoder audio offsets in hertz, not RF frequencies.

40m

UTC    dB Audio  Message
211130  -4 2034  BG2GWN F4JDM JN07
211200  +5 1978  CQ F4JDM JN07
211215  -9 1678  F4JDM ON1DGN -01
211230  +7 1978  ON1DGN F4JDM R+12
211245  -7 1677  F4JDM ON1DGN RR73
211300  -4 1978  ON1DGN F4JDM 73
211400  -5 1978  CQ F4JDM JN07 (x2)
211500  -2 1952  DS5USH F4JDM JN07 (x3)
211630  +3 1952  CQ F4JDM JN07 (x4)

10m

UTC    dB Audio  Message
153315 -17 2041  CQ F4JDM JN07 (x3)

80m

UTC    dB Audio  Message
205215 -17 1428  F4JDM CT3HU -07

20m

UTC    dB Audio  Message
211100  -6 1933  JR5MJS F4JDM 73
211515  +2 1933  BI6PWL F4JDM JN07 (x4)
211900  +8 1933  JA9NFO F4JDM JN07 (x2)
212215  +3 1933  OY5T F4JDM JN07 (x3)
194730  -1 1933  BU2FW F4JDM JN07 (x3)
201800  -1  557  F4JDM A61QQ -15 (x2)

Decoder S/N history by band

Count-weighted daily averages across messages attributed to this profiled token and successfully decoded at SO8OO, limited to the rolling 90-day UTC chart window.

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