RK4CH — FT8 activity observed at SO8OO

DXCC entity inferred from callsign: European Russia Most frequent locator attributed to this token: LO32

Receiver-side FT8 activity involving RK4CH, decoded by SO8OO in southeastern Poland. 1,319 FT8 messages attributed to this token as transmitter, on 80m, 40m, 20m, 10m, across 46 UTC dates in the available aggregate history. Observed between 2026-06-25 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 1,319 FT8 messages attributed to RK4CH as the transmitting token by decoded message structure across 46 UTC dates in the available aggregate history. The largest monitored-band total was 40 m (35%), followed by 20 m (35%) and 80 m (30%). Most decodes (55%) fell within the six-hour window 00:00-06:00 UTC. Received S/N was mixed across SO8OO's weak, moderate and strong ranges; the estimated median was -9 dB.

Overview

1,319

Messages attributed

UTC dates decoded

198

Active 15-min windows

-9 dB

Estimated median S/N

Bands

80m · 397 40m · 459 20m · 459 10m · 4

First attributed message: 2026-06-25
Last attributed message: 2026-09-12 02:58 UTC

Observed FT8 message patterns

Attributed sample: 1,319 messages
Active dates: 46 UTC dates
Estimated median S/N: -9 dB
Estimated 10th-90th percentile: -18 to +1 dB
Recurring-pattern threshold: Met

SO8OO display ranges among successful decodes: weak (≤ -16 dB) 231, moderate (-15 to -9 dB) 459, strong (≥ -8 dB) 629.

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 RK4CH in decoded directed-looking exchanges:

8S7DL · Sweden ×3 DC1KN · Fed. Rep. of Germany ×2 SM7TZK · Sweden ×2 R4HLO · European Russia ×2 EW8DG · Belarus ×2 RU3GF · European Russia ×2 TM2WWA · France ×2 DL6MRM · Fed. Rep. of Germany ×2 R5AV · European Russia ×2 YO4KMU · Romania ×2 W4DXM · United States ×2 RN3ZBX · European Russia ×2

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 RK4CH

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: LO32 · 781 decoded messages
SO8OO receiver locator: KN09VW
Locator-centre separation: 1,769 km (approx.)
Last such locator decoded: 2026-09-12 02:58 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	RK4CH S/N	Counterpart	Counterpart S/N	Msgs	Capture
09-12 02:45	40m	-11 / -	HF100PKP	- / -7	5	Partial capture
09-12 02:38	80m	-7 / -20	EA3HMM	-7 / -12	8	✓ Full exchange observed
09-12 02:37	80m	-14 / -15	TF3VS	-8 / -11	4	✓ Full exchange observed
09-12 02:35	40m	-8 / -7	AM42SDC	-14 / -15	3	Partial capture
09-12 02:33	40m	-8 / -	SM7TZK	-20 / +6	5	✓ Closing observed
09-12 02:32	40m	-4 / -	II0CDS	- / -	2	Partial capture
09-11 14:57	40m	-9 / -	UA9UFJ	- / +4	3	✓ Closing fragment
09-11 14:56	40m	-7 / -	RV9WJP	- / -16	3	✓ Closing fragment
09-11 14:54	40m	-14 / -4	SP9UOP	+2 / -12	4	✓ Full exchange observed
09-11 14:50	40m	-15 / -	UA3SCU	-14 / -	5	✓ Full exchange observed
09-11 14:46	40m	-6 / -	UB3ADO/P	- / 0	4	✓ Closing fragment
09-11 14:45	40m	- / -	RT2P	-19 / -	2	✓ Closing fragment
09-11 14:41	40m	-16 / -	RT2P	- / -	3	Partial capture
09-11 01:53	80m	-6 / -	OE8DDX	- / -	6	Partial capture
09-10 06:25	40m	- / +1	RA6OQ	-13 / -	2	✓ Closing fragment
09-10 02:16	40m	- / -21	HC2GRC	-12 / -	2	✓ Closing fragment
09-10 01:59	80m	-11 / -	SQ9RKE	- / -	3	Partial capture
09-10 01:39	80m	- / -11	GM6URC	-7 / -	3	Partial capture
09-10 01:32	80m	- / -	ON4MAP	-16 / -	6	Partial capture
09-10 01:28	80m	- / -8	GM6URC	-5 / -	5	Partial capture
09-10 01:27	80m	-12 / +5	R5AV	+3 / +8	4	✓ Full exchange observed
09-10 01:24	80m	-8 / +3	UA3IDQ	-24 / -9	5	✓ Full exchange observed
09-09 13:48	40m	-17 / -	YC8PST	- / -	3	Partial capture
09-03 02:22	40m	-8 / -	RI1FJL	- / -10	4	Partial capture
09-03 02:06	80m	-20 / -	MM0HVU	- / -16	2	✓ Closing fragment
09-03 02:04	80m	-9 / +4	R9WCK	-15 / -	3	✓ Closing observed
09-02 02:15	40m	-16 / -	SP9YGD	- / -	2	Partial capture
09-02 00:59	80m	-12 / -17	E74MW	+14 / -3	5	✓ Full exchange observed
09-01 02:37	40m	-8 / -	DH8KAM	- / -2	7	✓ Closing fragment
09-01 02:23	40m	-11 / -	G5GDX	- / -	2	Partial capture
09-01 02:22	40m	-8 / -	HB10GBT	- / -	2	Partial capture
09-01 02:18	40m	-9 / -	KP4LCA	- / -	6	Partial capture
09-01 02:15	40m	-9 / -	M0LAD	- / -	3	Partial capture
09-01 02:12	40m	-3 / -	UB8AHK	- / -	5	Partial capture
09-01 02:10	40m	-4 / -	SQ2BXI	- / -3	2	✓ Closing fragment
09-01 02:08	40m	-9 / -1	RM8L	-10 / -	3	✓ Closing observed
09-01 02:05	40m	-5 / -	PA3EY	- / -16	5	✓ Closing fragment
09-01 01:59	40m	-10 / -12	PT7YV	-4 / -	5	✓ Closing observed
09-01 01:55	40m	-8 / -	F1POK	- / -16	2	✓ Closing fragment
09-01 01:53	40m	-2 / -20	HA9OA	-11 / -	2	✓ Closing observed
09-01 01:52	40m	-9 / -	E75C	- / -9	3	✓ Closing fragment
09-01 01:47	80m	-9 / -6	IR7MGGC	0 / -8	5	✓ Full exchange observed
09-01 01:46	80m	- / -	EA5HM	-12 / -	2	Partial capture
09-01 01:46	80m	-10 / -9	SP9YGD	+6 / -5	8	✓ Full exchange observed
09-01 01:45	80m	-12 / -8	DO2NM	-5 / -17	4	✓ Full exchange observed
09-01 01:44	80m	-14 / -10	SV9QWC	-10 / -9	5	✓ Full exchange observed
08-31 12:35	20m	-2 / -	TA7D	- / -	3	Partial capture
08-31 12:32	20m	+4 / -	TA7D	- / -	2	Partial capture
08-31 11:46	20m	-7 / -	OE3MZC	- / -10	3	✓ Closing fragment
08-31 11:39	20m	-10 / -	LA8OOA	- / -7	3	✓ Closing fragment

Recent FT8 messages decoded at SO8OO

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

40m

UTC    dB Audio  Message
023345 -12 1540  SM7TZK RK4CH LO32 (x3)
023500 -20 1540  RK4CH SM7TZK 73
023545  -6 2108  AM42SDC RK4CH LO32
023600 -14 2106  RK4CH AM42SDC -07
023615 -10 2107  AM42SDC RK4CH R-15
024545 -10 2310  HF100PKP RK4CH LO32 (x5)
025230 -14 2495  J38LD RK4CH LO32 (x3)

80m

UTC    dB Audio  Message
015545  -8  914  OE8DDX RK4CH LO32 (x2)
023715 -16 2072  CQ RK4CH LO32
023745 -12 1105  TF3VS RK4CH -11
023800  -9 1103  RK4CH TF3VS R-15
023815 -15 1104  TF3VS RK4CH RR73
023830  -8  311  RK4CH EA3HMM JN00
023830  -7 1103  RK4CH TF3VS 73
023900 -10  311  RK4CH EA3HMM JN00
023915 -10  313  EA3HMM RK4CH -12
023930  -6  311  RK4CH EA3HMM JN00
023945  -3  312  EA3HMM RK4CH -15
024000  -4  311  RK4CH EA3HMM R-20
024015  -7  314  EA3HMM RK4CH RR73
024030  -5  311  RK4CH EA3HMM 73

20m

UTC    dB Audio  Message
041000  -4 2064  RK0SWA RK4CH LO32 (x3)
062215  +2 1509  IV3APC RK4CH LO32
113900  -9 1493  LA8OOA RK4CH LO32 (x3)
114615  -8 1408  OE3MZC RK4CH LO32 (x3)
123200  +5  857  TA7D RK4CH LO32 (x5)

10m

UTC    dB Audio  Message
093345  -2 2766  RK4CH DO1NUE -13 (x2)
075815 -13  576  RK4CH DN9BB -15 (x2)
080045 -15 1056  RK4CH OZ1MAX -12 (x3)
083830 -14 1830  RK4CH RU3GF RR73
091230 -13 1068  RK4CH RK6DL -05 (x2)
103115 -10 2324  RK4CH IZ5SIH -10 (x2)
063345 -13 1612  RK4CH RA3QPY +09 (x2)
062545 -17 1757  RK4CH RX6LG -08

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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