KW4J — FT8 activity observed at SO8OO

DXCC entity inferred from callsign: United States Most frequent locator attributed to this token: EM63

Receiver-side FT8 activity involving KW4J, decoded by SO8OO in southeastern Poland. 6 FT8 messages attributed to this token as transmitter, on 20m, across 2 UTC dates in the available aggregate history. Observed between 2026-06-10 and 2026-06-17.

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 6 FT8 messages attributed to KW4J as the transmitting token by decoded message structure across 2 UTC dates in the available aggregate history. The largest monitored-band total was 20 m (100%). In this small sample, the estimated median decoder S/N was -12 dB; no usual signal pattern is inferred.

Overview

Messages attributed

UTC dates decoded

Active 15-min windows

-12 dB

Estimated median S/N

Bands

20m · 6

First attributed message: 2026-06-10
Last attributed message: 2026-06-17 00:34 UTC

Observed FT8 message patterns

Attributed sample: 6 messages
Active dates: 2 UTC dates
Estimated median S/N: -12 dB
S/N percentile sample: Too small
Recurring-pattern threshold: Not met

SO8OO display ranges among successful decodes: weak (≤ -16 dB) 0, moderate (-15 to -9 dB) 5, strong (≥ -8 dB) 1.

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. The sample does not meet the threshold for a recurring time or signal-pattern claim (20 attributed messages, three UTC dates and five distinct 15-minute windows).

Frequent counterpart tokens observed at SO8OO

Tokens most often paired with KW4J in decoded directed-looking exchanges:

F4LWD · France 7Z1BQ · Saudi Arabia CT1END/P · Portugal M9KTM · England OK4SD · Czech Republic R6OD · European Russia RT3K · European Russia RX7K · European Russia RZ9A · Asiatic Russia 9A9TT · Croatia DL9KM · Fed. Rep. of Germany PA4PA · Netherlands

Most frequent locator attributed to KW4J

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: EM63
SO8OO receiver locator: KN09VW
Locator-centre separation: 8,401 km (approx.)
Last such locator decoded: 2026-06-17 00:34 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	KW4J S/N	Counterpart	Counterpart S/N	Msgs	Capture
09-06 00:21	60m	- / -16	PA4PA	+9 / -	3	✓ Closing fragment
08-24 01:01	40m	- / -	9A4ZM	+1 / -	3	Partial capture
08-15 20:30	20m	- / -16	M9KTM	+2 / -	8	✓ Closing fragment
08-14 21:01	20m	- / -	HB9MEJ	-14 / -	2	Partial capture
08-13 22:06	20m	- / -15	7Z1BQ	-20 / -	2	✓ Closing fragment
08-12 21:24	20m	- / -16	OK4SD	+6 / -	2	✓ Closing fragment
08-11 00:28	60m	- / -16	OZ7FOC	-17 / -	4	Partial capture
08-11 00:23	60m	- / -11	SP0DF	-3 / -	3	✓ Closing fragment
08-11 00:13	40m	- / -6	DL9KM	-20 / -	3	✓ Closing fragment
08-11 00:08	40m	- / -10	9A9TT	-15 / -	2	✓ Closing fragment
08-08 03:11	20m	- / -26	RZ9A	-20 / -	2	✓ Closing fragment
08-08 02:23	20m	- / -12	RW9WT	-2 / -	3	Partial capture
08-08 02:21	20m	- / -	RV9WF	-6 / -	2	Partial capture
07-11 17:46	20m	- / -	G4CTY	-21 / -	2	Partial capture
06-24 20:53	20m	- / -11	RX7K	-10 / -	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
000800 -15 1288  KW4J 9A9TT -10 (x2)
001330  -6  385  KW4J IK6DLK JN63
001330 -18 1420  KW4J DL9KM JN68 (x3)
001945 -18 1834  KW4J SP0DF JO73
010115  +5 2547  KW4J 9A4ZM JN86 (x3)
010615  -8 2472  KW4J S56KO RRR
005700 -13  283  KW4J K8AGB EN90

60m

UTC    dB Audio  Message
002345  -4 1830  KW4J SP0DF JO73 (x3)
002800 -16 1251  KW4J OZ7FOC -16 (x4)
002145  +7  432  KW4J PA4PA -16 (x3)

20m

UTC    dB Audio  Message
212430  +4 3077  KW4J OK4SD -16 (x2)
220600 -21 1771  KW4J 7Z1BQ -15 (x2)
210130 -15 2100  KW4J HB9MEJ JN47 (x2)
203000  +3  942  KW4J M9KTM IO91 (x8)
202845 -17 1481  KW4J CT1END/P RR73

10m

UTC    dB Audio  Message
142245 -17 1140  KW4J F4LWD RR73

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