UI4F — FT8 activity observed at SO8OO

DXCC entity inferred from callsign: European Russia Most frequent locator attributed to this token: LO21

Receiver-side FT8 activity involving UI4F, decoded by SO8OO in southeastern Poland. 105 FT8 messages attributed to this token as transmitter, on 40m, 20m, across 7 UTC dates in the available aggregate history. Observed between 2026-07-17 and 2026-08-12.

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 105 FT8 messages attributed to UI4F as the transmitting token by decoded message structure across 7 UTC dates in the available aggregate history. The largest monitored-band total was 20 m (70%), followed by 40 m (30%). Most decodes (87%) fell within the six-hour window 12:00-18:00 UTC. Received S/N was mixed across SO8OO's weak, moderate and strong ranges; the estimated median was -9 dB.

Overview

105

Messages attributed

UTC dates decoded

Active 15-min windows

-9 dB

Estimated median S/N

Bands

40m · 31 20m · 74

First attributed message: 2026-07-17
Last attributed message: 2026-08-12 08:34 UTC

Observed FT8 message patterns

Attributed sample: 105 messages
Active dates: 7 UTC dates
Estimated median S/N: -9 dB
Estimated 10th-90th percentile: -17 to +2 dB
Recurring-pattern threshold: Met

SO8OO display ranges among successful decodes: weak (≤ -16 dB) 15, moderate (-15 to -9 dB) 42, strong (≥ -8 dB) 48.

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 UI4F in decoded directed-looking exchanges:

A41ZZ · Oman BD6IIC · China HB9IIO · Switzerland KF0YOB · United States RK6OV · European Russia VK2WW · Australia VO1IV · Canada WV2B · United States YB5NHD · Indonesia YB5SD · Indonesia YF3ARV · Indonesia BA6IM · China

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 UI4F

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: LO21 · 57 decoded messages
SO8OO receiver locator: KN09VW
Locator-centre separation: 1,636 km (approx.)
Last such locator decoded: 2026-08-12 08:34 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	UI4F S/N	Counterpart	Counterpart S/N	Msgs	Capture
08-12 08:33	20m	+10 / -	HZ1YJ	- / -	2	Partial capture
08-12 08:32	20m	+8 / -	RK0SC	- / -	3	Partial capture
08-10 15:37	40m	-14 / -	RT7N	- / -1	2	✓ Closing fragment
08-10 15:35	40m	-12 / -	RY9W	- / -6	3	✓ Closing fragment
08-10 15:33	40m	-14 / -	R9ZAH	- / -14	3	✓ Closing fragment
08-10 15:31	40m	-14 / -	R9OON	- / -6	2	✓ Closing fragment
08-02 10:58	20m	+6 / -	HI8UD	- / -	3	Partial capture
07-31 16:56	20m	-18 / -	3B8GL	- / -	2	Partial capture
07-31 16:43	40m	-8 / +2	UA1AEL	-18 / -5	4	✓ Full exchange observed
07-31 16:41	40m	-12 / -	RW3XB	- / +1	4	✓ Closing fragment
07-31 16:26	20m	-8 / -	3B8GL	- / -	6	Partial capture
07-31 16:24	20m	-12 / -	VO1IV	- / -22	3	✓ Closing fragment
07-31 16:21	20m	-11 / -	BD6IIC	- / -12	2	✓ Closing fragment
07-31 16:21	20m	-6 / -	3B8GL	- / -	4	Partial capture
07-31 13:16	20m	+5 / -	YF3ARV	- / -12	3	✓ Closing fragment
07-31 13:12	20m	-3 / -	WV2B	- / -17	2	✓ Closing fragment
07-31 13:11	20m	0 / -	W4DXM	- / -19	6	Partial capture
07-31 13:06	20m	-2 / -	W4DXM	- / -	2	Partial capture
07-31 13:04	20m	0 / -	A41ZZ	- / -4	2	✓ Closing fragment
07-31 13:03	20m	-6 / -	YB5SD	- / -11	2	✓ Closing fragment
07-31 13:01	20m	-5 / -	VK2SMP	- / -	3	Partial capture
07-31 12:58	20m	0 / -	VK2WW	- / -13	3	✓ Closing fragment
07-31 12:57	20m	-2 / -	VE2OPR	- / -	2	Partial capture
07-19 15:33	20m	-10 / -	YB6IDM	- / -	2	Partial capture
07-19 15:23	20m	-12 / -	YB5NHD	- / -9	2	✓ Closing fragment
07-19 15:21	20m	-9 / -	YB6IDM	- / -	2	Partial capture
07-19 15:18	20m	-10 / -8	HB9IIO	-20 / -18	3	✓ Full exchange observed
07-19 15:16	20m	-10 / -	K0C	- / -	2	Partial capture
07-18 09:43	20m	- / -12	PE1MHY	-23 / -	2	Partial capture
07-17 18:24	40m	-14 / -	R8CJG	- / -	3	✓ Closing fragment
07-17 17:55	20m	-14 / -	KF0YOB	- / -18	6	✓ Closing fragment
07-17 17:53	20m	-23 / -	TN8GD	- / -12	3	Partial capture
07-17 17:48	40m	-17 / -	RC6OX	- / -4	2	✓ Closing fragment
07-17 17:47	40m	-15 / -	VJ6X	- / -24	3	✓ Closing fragment

Recent FT8 messages decoded at SO8OO

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

20m

UTC    dB Audio  Message
162800 -11  275  3B8GL UI4F LO21 (x4)
105345 -11 1154  HI8UD UI4F LO21 (x5)
143545 -22 1894  UI4F EA5HEU JN00
083245  +7 2930  RK0SC UI4F LO21 (x2)
083345 +11 2931  HZ1YJ UI4F LO21 (x2)
083445  +8 2931  RK0SC UI4F LO21

40m

UTC    dB Audio  Message
164400 -18 1153  UI4F UA1AEL RR73
144830 -13  931  UI4F RK6MC RR73
145745 -17 2275  <...> UI4F LO21
150045 -18 2275  UA9ZZ UI4F LO21
153130 -14 2487  R9OON UI4F R-06 (x2)
153300 -13 2487  R9ZAH UI4F LO21 (x3)
153430 -12 2487  YH6AI UI4F LO21
153530 -11 2487  RY9W UI4F -06 (x3)
153700 -14 2487  RT7N UI4F -01 (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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