RK4CH — FT8 activity observed at SO8OO
Receiver-side FT8 activity involving RK4CH, decoded by SO8OO in southeastern Poland. 1,443 FT8 messages attributed to this token as transmitter, on 80m, 40m, 20m, 10m, across 50 UTC dates in the available aggregate history. Observed between 2026-06-25 and 2026-09-18.
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 1,443 FT8 messages attributed to RK4CH as the transmitting token by decoded message structure across 50 UTC dates in the available aggregate history. The largest monitored-band total was 40 m (37%), followed by 20 m (32%) and 80 m (31%). Most decodes (59%) 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
Bands
Last attributed message: 2026-09-18 03:56 UTC
Observed FT8 message patterns
- Attributed sample
- 1,443 messages
- Active dates
- 50 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) 245, moderate (-15 to -9 dB) 497, strong (≥ -8 dB) 701.
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:
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 · 856 decoded messages
- SO8OO receiver locator
- KN09VW
- Locator-centre separation
- 1,769 km (approx.)
- Last such locator decoded
- 2026-09-18 03:55 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 |
|---|---|---|---|---|---|---|
| 09-18 12:53 | 40m | - / -3 | R3PMI | -20 / - | 2 | ✓ Closing fragment |
| 09-18 12:31 | 40m | - / -19 | EU2ABK | -8 / - | 2 | Partial capture |
| 09-18 03:55 | 40m | -5 / - | UB8AHK | - / -13 | 3 | ✓ Closing fragment |
| 09-18 03:24 | 40m | +1 / +8 | R3BEZ | -14 / -8 | 6 | ✓ Full exchange observed |
| 09-18 03:20 | 40m | -5 / -10 | F5MOO | +8 / -10 | 6 | ✓ Full exchange observed |
| 09-18 03:02 | 40m | -18 / - | RT8T | - / - | 4 | Partial capture |
| 09-18 02:41 | 40m | -7 / -16 | IQ0AAI | +5 / -18 | 5 | ✓ Full exchange observed |
| 09-18 02:32 | 40m | -4 / +7 | R8CKD | -4 / - | 6 | ✓ Closing observed |
| 09-18 02:31 | 40m | -19 / -6 | UB6HJZ | -13 / -8 | 6 | ✓ Full exchange observed |
| 09-18 02:28 | 40m | -9 / -16 | RN4LP | +8 / -18 | 5 | ✓ Full exchange observed |
| 09-18 02:23 | 40m | +4 / - | R8CKD | -6 / +4 | 7 | Partial capture |
| 09-18 02:22 | 40m | -14 / -3 | IS0AAS | -12 / -13 | 5 | ✓ Full exchange observed |
| 09-16 02:29 | 40m | -13 / - | F4JIS | - / - | 2 | Partial capture |
| 09-16 02:19 | 80m | -6 / -8 | SQ6ELK | -3 / -5 | 4 | ✓ Full exchange observed |
| 09-16 02:14 | 80m | - / - | ON4MAP | -14 / - | 2 | Partial capture |
| 09-16 02:08 | 80m | -13 / -16 | DO1OAS | +3 / -14 | 5 | ✓ Full exchange observed |
| 09-15 03:52 | 40m | -10 / - | R6HV/P | - / -5 | 2 | ✓ Closing fragment |
| 09-15 03:47 | 40m | -4 / - | DJ3AA | - / -11 | 8 | ✓ Closing fragment |
| 09-15 03:14 | 40m | -12 / - | SQ3LMR | - / -14 | 7 | Partial capture |
| 09-15 02:27 | 40m | +1 / - | 8S2C | - / -6 | 3 | ✓ Closing fragment |
| 09-15 01:45 | 40m | -10 / - | OH2XX | - / - | 2 | Partial capture |
| 09-15 01:40 | 40m | -3 / - | EI4GAB | - / - | 4 | Partial capture |
| 09-15 01:29 | 40m | -10 / - | RA0WBI | - / -11 | 2 | Partial capture |
| 09-15 00:59 | 80m | -10 / -24 | F5NNN | -1 / -17 | 8 | ✓ Full exchange observed |
| 09-15 00:39 | 80m | -14 / -2 | SQ8NA | +10 / - | 3 | ✓ Closing observed |
| 09-15 00:13 | 80m | - / - | ON4MAP | -11 / - | 5 | Partial capture |
| 09-15 00:12 | 80m | -2 / -12 | R4FDK | -6 / +6 | 5 | ✓ Full exchange observed |
| 09-15 00:10 | 80m | +2 / -14 | EX7DY | -10 / - | 2 | ✓ Closing observed |
| 09-15 00:08 | 80m | -4 / -1 | RD0L/3 | -14 / +9 | 3 | Partial capture |
| 09-14 14:11 | 40m | -18 / -18 | R70SAB | -9 / - | 4 | ✓ Full exchange observed |
| 09-14 13:25 | 40m | - / +2 | RW3PI | -12 / - | 3 | Partial capture |
| 09-14 13:20 | 40m | -20 / - | RA0AB | - / -15 | 2 | Partial 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 |
Recent FT8 messages decoded at SO8OO
Frequency values are decoder audio offsets in hertz, not RF frequencies.
UTC dB Audio Message 032415 +1 789 R3BEZ RK4CH LO32 (x2) 032500 -14 788 RK4CH R3BEZ +08 032515 +1 788 R3BEZ RK4CH R-08 032530 -14 789 RK4CH R3BEZ RR73 032545 -1 790 R3BEZ RK4CH 73 034230 -11 1866 RT8T RK4CH LO32 034630 -15 1127 RA3MT RK4CH 73 035530 -13 963 UB8AHK RK4CH LO32 (x3) 123100 -11 1535 RK4CH EU2ABK -19 (x2) 125330 -19 1744 RK4CH R3PMI -03 (x2)
UTC dB Audio Message 021315 -8 1004 CQ RK4CH LO32 (x3) 021430 -14 1242 RK4CH ON4MAP JO20 021445 -4 1004 CQ RK4CH LO32 (x4) 021630 -15 1242 RK4CH ON4MAP JO20 021645 -1 1004 CQ RK4CH LO32 (x2) 021945 -2 1715 RK4CH SQ6ELK -08 022000 -2 1716 SQ6ELK RK4CH R-05 022015 -4 1715 RK4CH SQ6ELK RR73 022030 -9 1716 SQ6ELK RK4CH 73
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)
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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