RK4UZ — FT8 activity observed at SO8OO

DXCC entity inferred from callsign: European Russia Most frequent locator attributed to this token: LO24

Receiver-side FT8 activity involving RK4UZ, decoded by SO8OO in southeastern Poland. 1,294 FT8 messages attributed to this token as transmitter, on 80m, 40m, 20m, 10m, across 85 UTC dates in the available aggregate history. Observed between 2026-06-06 and 2026-10-05.

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 1,294 FT8 messages attributed to RK4UZ as the transmitting token by decoded message structure across 85 UTC dates in the available aggregate history. The largest monitored-band total was 40 m (38%), followed by 20 m (36%) and 80 m (26%). Most decodes (79%) fell within the six-hour window 13:00-19:00 UTC. Received S/N was mixed across SO8OO's weak, moderate and strong ranges; the estimated median was -9 dB.

Overview

1,294

Messages attributed

UTC dates decoded

271

Active 15-min windows

-9 dB

Estimated median S/N

Bands

80m · 334 40m · 488 20m · 471 10m · 1

First attributed message: 2026-06-06
Last attributed message: 2026-10-05 05:10 UTC

Observed FT8 message patterns

Attributed sample: 1,294 messages
Active dates: 85 UTC dates
Estimated median S/N: -9 dB
Estimated 10th-90th percentile: -18.9 to +2 dB
Recurring-pattern threshold: Met

SO8OO display ranges among successful decodes: weak (≤ -16 dB) 272, moderate (-15 to -9 dB) 428, strong (≥ -8 dB) 594.

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 RK4UZ in decoded directed-looking exchanges:

OK1UOZ · Czech Republic ×2 R9HFA · Asiatic Russia ×2 EU6UE · Belarus ×2 R2AVW · European Russia ×2 R3NAW · European Russia ×2 RD7O · European Russia ×2 RV3X · European Russia ×2 UA3IDQ · European Russia ×2 R2PT · European Russia ×2 R4HEN · European Russia ×2 RA6ATZ · European Russia ×2 EA7BEM · Spain

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 RK4UZ

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: LO24 · 773 decoded messages
SO8OO receiver locator: KN09VW
Locator-centre separation: 1,652 km (approx.)
Last such locator decoded: 2026-10-05 05:09 UTC

Other locator fields attributed to this token: LA24 (3).

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	RK4UZ S/N	Counterpart	Counterpart S/N	Msgs	Capture
10-05 05:08	40m	-12 / -9	MI7XHT	-18 / -23	5	✓ Full exchange observed
10-05 04:22	40m	-9 / -24	II5GG	-12 / -17	4	✓ Full exchange observed
10-05 04:14	40m	- / -6	R6AR	-9 / -	3	✓ Closing fragment
10-05 03:54	40m	-3 / -14	HC2GRC	-11 / -22	6	✓ Full exchange observed
10-05 03:49	40m	-14 / -	R8CKV	- / -8	5	✓ Closing fragment
10-04 12:54	40m	-9 / +4	R80SAA	-4 / -	3	✓ Closing observed
10-03 16:21	80m	+2 / -2	RA4FWB	-17 / +1	7	✓ Full exchange observed
10-03 16:17	80m	+1 / +7	RA6Z	-2 / -	4	✓ Closing observed
10-03 16:14	80m	+3 / -	OH3GBW	- / -	3	Partial capture
10-03 16:11	80m	+2 / -3	R3ZBY	-11 / -2	6	✓ Full exchange observed
10-03 16:09	80m	+1 / -	UB0SMX/P	- / -19	3	✓ Closing fragment
10-03 16:05	80m	+5 / -	R2OM	- / -14	3	✓ Closing fragment
10-03 16:00	80m	0 / -4	RW9MZ	-23 / -13	4	✓ Full exchange observed
10-02 14:33	40m	-3 / -13	RK6OU	-4 / +2	6	✓ Full exchange observed
10-02 14:29	40m	-7 / -	E25KAE	- / -18	3	✓ Closing fragment
10-01 16:20	80m	- / -4	SV1DOO	-12 / -	2	✓ Closing fragment
10-01 16:10	80m	-17 / -	RV3IN	-4 / -6	6	✓ Full exchange observed
10-01 16:08	80m	-16 / -	RN3QN	- / -	3	Partial capture
10-01 16:02	40m	- / -4	RV3H	-18 / -	2	✓ Closing fragment
10-01 15:53	40m	-14 / -	BX4AQ	- / -	2	✓ Closing fragment
09-30 17:35	80m	- / -	R4CCW	-10 / -	2	✓ Closing fragment
09-30 17:33	80m	-8 / -	RA3ZOM	- / -23	2	✓ Closing fragment
09-30 17:30	80m	-4 / +6	R3KV	-13 / -5	6	✓ Full exchange observed
09-30 17:28	80m	-5 / -	RQ3D	- / -6	3	✓ Closing fragment
09-29 15:27	80m	-18 / +1	RY7F	-12 / -1	7	✓ Full exchange observed
09-29 15:20	40m	-18 / -	BA6IM	- / -	3	Partial capture
09-29 15:19	80m	- / -	OZ1HPS	-24 / -	2	Partial capture
09-28 16:40	80m	-16 / -	R4HKO	-19 / -	2	✓ Closing observed
09-28 16:17	80m	-10 / +3	UN0GY	-15 / -11	6	✓ Full exchange observed
09-27 17:14	80m	-6 / -	UB9WPD	- / -14	4	✓ Closing fragment
09-27 17:08	80m	-3 / -	RA3ZOM	- / -	6	Partial capture
09-27 16:58	80m	-3 / -	UB3KGW	- / -7	3	✓ Closing fragment
09-27 16:28	80m	-12 / -9	RO6OP	-10 / -6	7	✓ Full exchange observed
09-27 16:26	80m	-8 / -	UF3T	+5 / +5	10	✓ Full exchange observed
09-27 16:19	40m	-10 / -	UB6LUR	- / -	4	Partial capture
09-27 16:13	40m	-11 / -	RO6OP	- / -	2	Partial capture
09-27 06:19	40m	- / -	SP1ZMO	-1 / -	5	Partial capture
09-27 03:29	80m	-11 / -20	UA6Q/M	-3 / -18	2	Partial capture
09-26 17:28	80m	-2 / -	OH3DJP	- / -24	3	✓ Closing fragment
09-26 17:27	80m	-24 / -	RU3KV	-19 / -	2	✓ Closing observed
09-26 17:22	80m	-10 / -	RT4A/P	- / -8	2	✓ Closing fragment
09-26 17:20	80m	-12 / -	R3KLE	- / -1	3	✓ Closing fragment
09-26 17:13	80m	0 / +10	RU3OW	-2 / +2	8	✓ Full exchange observed
09-26 17:12	80m	0 / +6	RV3X	+2 / -2	4	✓ Full exchange observed
09-25 16:26	80m	-14 / -10	RA9FDR	-19 / -7	3	✓ Full exchange observed
09-25 16:23	80m	- / -	PA3FPQ	-3 / -	3	Partial capture
09-25 16:17	80m	-15 / -	R8DX	-5 / -5	6	✓ Closing observed
09-25 16:15	80m	-13 / -13	R0AH	-20 / -17	4	✓ Full exchange observed
09-25 16:00	40m	-16 / -	R3EEO	- / 0	2	✓ Closing fragment
09-25 05:13	40m	-5 / -8	RN6LAJ	-6 / -	3	✓ Closing observed

Recent FT8 messages decoded at SO8OO

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

40m

UTC    dB Audio  Message
040115  -9 2718  9H4JX RK4UZ R-14
041400  -7 1418  RK4UZ R6AR -06 (x3)
042045 -10 1881  RK4UZ LZ936BA -06
042245 -12 2619  II5GG RK4UZ LO24
042300 -12 2476  RK4UZ II5GG -24
042345  -7 2619  II5GG RK4UZ R-17 (x2)
050815 -10 2619  MI7XHT RK4UZ LO24
050915  -9 2619  CQ RK4UZ LO24
050930 -17 2303  RK4UZ MI7XHT -09
050945 -12 2620  MI7XHT RK4UZ R-23
051000 -20 2303  RK4UZ MI7XHT RR73
051015 -13 2619  MI7XHT RK4UZ 73

80m

UTC    dB Audio  Message
161745  -1 2669  RK4UZ RA6Z R+07
161800  +1 2669  RA6Z RK4UZ RR73
161815  -2 2670  RK4UZ RA6Z 73
161915  +0 2670  RU3ACA RK4UZ LO24
162130  +5 2669  RA4FWB RK4UZ LO24 (x2)
162245 -18 1841  RK4UZ RA4FWB -02 (x2)
162330  +3 2670  RA4FWB RK4UZ R+01
162345 -15 1840  RK4UZ RA4FWB RR73
162400  +1 2670  RA4FWB RK4UZ 73
034400  -5 1769  CQ RK4UZ LO24 (x4)

20m

UTC    dB Audio  Message
150645  +5 2022  RI1FJL RK4UZ LO24 (x7)
133430  -2 1927  R9WJ RK4UZ LO24 (x2)
133515  -7 1927  RK4UZ R9WJ RR73
133530  -4 1927  R9WJ RK4UZ 73
133600 -14 1927  W1YY RK4UZ R-12 (x2)
062815 -15 1916  OK1UOZ RK4UZ R-12 (x2)

10m

UTC    dB Audio  Message
144445 -11 2687  RK4UZ SM2LIY RR73
083100 -15 2375  RK4UZ R6DWD -12
083330  -6 2803  RK4UZ R6TA LN13 (x4)
083800 -19 2079  RK4UZ R6ZIG RR73
084315  +3 2787  RK4UZ R6OD RR73
084700 -12 1721  RK4UZ IK4IDF JN54 (x3)
085300  -6 1392  RK4UZ EA7BEM IM66 (x4)

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.

FT8DB and SO8OO WebSDR are a hobby project maintained solo. ☕ Buy me a coffee