4X1UF — FT8 activity observed at SO8OO

DXCC entity inferred from callsign: Israel Most frequent locator attributed to this token: KM72

Receiver-side FT8 activity involving 4X1UF, decoded by SO8OO in southeastern Poland. 27,440 FT8 messages attributed to this token as transmitter, on 160m, 80m, 60m, 40m, 20m, 10m, across 78 UTC dates in the available aggregate history. Observed between 2026-06-07 and 2026-09-04.

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 27,440 FT8 messages attributed to 4X1UF as the transmitting token by decoded message structure across 78 UTC dates in the available aggregate history. The largest monitored-band total was 20 m (49%), followed by 40 m (33%) and 10 m (8%). The busiest six-hour window was 19:00-01:00 UTC, containing 46% of decodes. Received S/N was mixed across SO8OO's weak, moderate and strong ranges; the estimated median was -9.3 dB.

Overview

27,440

Messages attributed

UTC dates decoded

2,105

Active 15-min windows

-9.3 dB

Estimated median S/N

Bands

160m · 8 80m · 1,954 60m · 963 40m · 8,981 20m · 13,417 10m · 2,117

First attributed message: 2026-06-07
Last attributed message: 2026-09-04 20:06 UTC

Observed FT8 message patterns

Attributed sample: 27,440 messages
Active dates: 78 UTC dates
Estimated median S/N: -9.3 dB
Estimated 10th-90th percentile: -16 to -1 dB
Recurring-pattern threshold: Met

SO8OO display ranges among successful decodes: weak (≤ -16 dB) 3,214, moderate (-15 to -9 dB) 12,161, strong (≥ -8 dB) 12,065.

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 4X1UF in decoded directed-looking exchanges:

TA7ARH · Asiatic Turkey ×5 TA2ED · Asiatic Turkey ×4 IZ4AIF · Italy ×4 TA3NK · Asiatic Turkey ×4 PD2WL · Netherlands ×4 YL3AVN · Latvia ×3 R1BPB · European Russia ×3 F1IQH · France ×3 BG4OOO · China ×3 EA8AID · Canary Islands ×3 S57MPU · Slovenia ×3 ON8DM · Belgium ×3

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 4X1UF

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: KM72 · 21,796 decoded messages
SO8OO receiver locator: KN09VW
Locator-centre separation: 2,224 km (approx.)
Last such locator decoded: 2026-09-04 20:06 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	4X1UF S/N	Counterpart	Counterpart S/N	Msgs	Capture
09-04 19:25	40m	- / -16	IW2CAK/2	-6 / -	2	Partial capture
09-04 19:24	40m	- / -	G6LSO	-9 / -	3	Partial capture
09-04 19:19	40m	-13 / -	EX7CQ	- / -	4	Partial capture
09-04 19:13	40m	-14 / -	EX7CQ	- / -	8	Partial capture
09-04 19:09	40m	-14 / -	R2APC	+4 / -5	4	✓ Closing observed
09-04 19:05	40m	- / -	R2APC	-6 / -	2	Partial capture
09-04 18:52	40m	- / -6	YU1AXY	-2 / -	3	✓ Closing fragment
09-04 18:49	40m	- / -7	DK2SW	+2 / -	5	✓ Closing fragment
09-04 18:40	40m	- / -11	DL1AA	0 / -	7	✓ Closing fragment
09-04 18:37	40m	- / -	F4MTS	+8 / -	4	Partial capture
09-04 18:21	40m	-13 / -	EX7CQ	- / -	19	Partial capture
09-04 18:14	40m	-12 / -	EA4LL	- / -22	2	Partial capture
09-04 18:12	40m	- / -22	2E0LMA	0 / -	3	✓ Closing fragment
09-04 18:11	40m	-8 / -13	R4HNW	-8 / -14	5	✓ Full exchange observed
09-04 18:04	40m	-15 / -17	IK7TOE	-2 / +7	4	✓ Full exchange observed
09-04 18:00	40m	-16 / -	RN3RHQ	-13 / -9	3	✓ Closing observed
09-04 17:56	40m	- / -	OH1TK	-6 / -	2	Partial capture
09-04 17:56	40m	-12 / -7	DK9EU	0 / -11	4	✓ Full exchange observed
09-04 17:53	40m	-10 / +1	SQ9HA	-9 / -11	3	✓ Full exchange observed
09-04 17:26	40m	- / -13	OZ4MK	-4 / -	3	✓ Closing fragment
09-04 17:24	40m	-14 / -1	SP8JUR	0 / -	3	✓ Closing observed
09-04 17:22	40m	- / -12	UT7NI	+2 / -	2	✓ Closing fragment
09-04 17:13	40m	-13 / -9	R2AVW	+6 / +1	3	✓ Full exchange observed
09-04 17:07	40m	-10 / -	RA0CGT	- / -9	6	✓ Closing fragment
09-04 16:56	40m	-12 / -	RA0CGT	- / -10	17	Partial capture
09-04 16:54	40m	-13 / -	RC2Y	-3 / -4	4	✓ Closing observed
09-04 16:48	40m	-18 / -17	DA1MHH	-7 / -16	5	✓ Full exchange observed
09-04 16:26	40m	-10 / -4	F4GPB	-6 / -5	5	✓ Full exchange observed
09-04 16:24	40m	-11 / -13	R8QA	-12 / -6	5	✓ Full exchange observed
09-04 05:25	60m	-15 / -	J88IH	- / -	2	Partial capture
09-04 05:07	60m	- / -25	IV3DSG	-9 / -	4	✓ Closing fragment
09-04 04:24	60m	-15 / -8	IU6JMK	-6 / +1	5	✓ Full exchange observed
09-04 04:10	60m	-15 / -9	IK2VFR/P	-9 / 0	4	✓ Full exchange observed
09-04 04:06	60m	-14 / +6	ER3UA	0 / 0	8	✓ Full exchange observed
09-04 04:04	60m	-16 / -10	OK4KOP	0 / -	4	✓ Closing observed
09-04 04:02	60m	-14 / +2	IW3GXW	-12 / -19	4	✓ Full exchange observed
09-04 03:59	60m	-14 / -18	ON8DM	-3 / -7	5	✓ Full exchange observed
09-04 03:48	60m	-12 / -2	OM5JG	-13 / -	22	Partial capture
09-04 03:24	60m	-6 / -20	VE3EY	-6 / -15	4	✓ Full exchange observed
09-04 03:14	60m	-7 / -	VE3FF	- / -6	2	✓ Closing fragment
09-04 03:13	60m	-6 / -	W4CHA	- / +2	2	✓ Closing fragment
09-04 03:10	60m	-6 / -	W3FAY	- / -13	2	✓ Closing fragment
09-04 03:07	60m	-4 / -	KC9OXP	- / -11	6	✓ Closing fragment
09-04 02:59	60m	- / +3	DL6RDE	-16 / -	2	Partial capture
09-04 02:51	60m	-3 / -11	K1OF	-21 / -2	7	✓ Full exchange observed
09-04 02:50	60m	-2 / -	WA0YPC	- / -13	2	✓ Closing fragment
09-04 02:48	60m	-2 / -	W1BS	- / -13	2	✓ Closing fragment
09-04 02:42	60m	- / -	K1OF	-16 / -	3	Partial capture
09-04 02:38	60m	+2 / -	DL9KM	-16 / -4	20	Partial capture
09-04 02:24	60m	-2 / -	WB2SIH	- / -6	4	✓ Closing fragment

Recent FT8 messages decoded at SO8OO

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

40m

UTC    dB Audio  Message
192515 -14  229  CQ 4X1UF KM72
192530 -10  228  4X1UF G6LSO IO84
192530  -7  425  <4X1UF> IW2CAK/2 (x2)
192645 -14  229  SP9DPM/P 4X1UF -14
195945 -15  229  CQ 4X1UF KM72 (x7)
200345 -15  229  JG3VTR 4X1UF -15 (x2)
200645 -11  229  CQ 4X1UF KM72

60m

UTC    dB Audio  Message
043515 -17  227  CQ 4X1UF KM72                         a1 (x6)
050730  -7  233  4X1UF IV3DSG JN66 (x4)
052515 -13 2543  J88IH 4X1UF KM72 (x2)
053045 -12 2542  CQ 4X1UF KM72
053115 -12 2542  MI0NWA 4X1UF KM72
053415 -15 2542  J88IH 4X1UF KM72

160m

UTC    dB Audio  Message
205400  +7  996  4X1UF 9A2RD JN65
205430  -3 2713  4X1UF SV8OVJ KM27 (x2)
205730 -18  915  4X1UF F9IE IN86 (x2)
205930  -9 2713  4X1UF SV8OVJ KM27 (x5)
212730  +3  873  4X1UF OM4MM JN98 (x3)
213030 -17 1151  4X1UF SQ9DXJ +02 (x2)

80m

UTC    dB Audio  Message
182400 +20  968  4X1UF UT2PC KO21
182415 -13 1170  P29YY 4X1UF KM72 (x2)
182445 +12  968  4X1UF UT2PC KO21 (x2)
182545 -14 1170  P29YY 4X1UF R-17 (x2)
182630 +21  968  4X1UF UT2PC KO21
182645 -11 1169  CQ 4X1UF KM72
182700 +21  968  4X1UF UT2PC KO21
182715 -14 1170  UT2PC 4X1UF -12
182730 +16  968  4X1UF UT2PC R-08
182745 -15 1169  UT2PC 4X1UF RR73
182800 +19  968  4X1UF UT2PC 73
182815 -19 1170  CQ 4X1UF KM72

20m

UTC    dB Audio  Message
050845  +0 2778  CQ 4X1UF KM72 (x15)

10m

UTC    dB Audio  Message
151730  -2 2802  4X1UF DN9WES JO30 (x2)
093330 -12 2659  4X1UF G8GNI IO91 (x3)
072815  -8 2612  4X1UF DL0NS JO31
074215 +12 2965  4X1UF DL1RNI JO62 (x9)

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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