YO4SX — FT8 activity observed at SO8OO
Receiver-side FT8 activity involving YO4SX, decoded by SO8OO in southeastern Poland. 578 FT8 messages attributed to this token as transmitter, on 80m, 40m, 20m, 10m, across 30 UTC dates in the available aggregate history. Observed between 2026-06-07 and 2026-09-15.
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 578 FT8 messages attributed to YO4SX as the transmitting token by decoded message structure across 30 UTC dates in the available aggregate history. The largest monitored-band total was 20 m (56%), followed by 40 m (38%) and 10 m (5%). Most decodes (87%) fell within the six-hour window 03:00-09:00 UTC. Received S/N was mixed across SO8OO's weak, moderate and strong ranges; the estimated median was -13 dB.
Overview
Bands
Last attributed message: 2026-09-15 06:23 UTC
Observed FT8 message patterns
- Attributed sample
- 578 messages
- Active dates
- 30 UTC dates
- Estimated median S/N
- -13 dB
- Estimated 10th-90th percentile
- -20 to -3 dB
- Recurring-pattern threshold
- Met
SO8OO display ranges among successful decodes: weak (≤ -16 dB) 202, moderate (-15 to -9 dB) 206, strong (≥ -8 dB) 170.
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 YO4SX 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 YO4SX
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
- KN44 · 333 decoded messages
- SO8OO receiver locator
- KN09VW
- Locator-centre separation
- 813 km (approx.)
- Last such locator decoded
- 2026-09-15 06:22 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 | YO4SX S/N | Counterpart | Counterpart S/N | Msgs | Capture |
|---|---|---|---|---|---|---|
| 09-15 06:21 | 40m | -19 / -4 | OK1AY | +3 / - | 4 | ✓ Closing observed |
| 09-15 06:20 | 40m | -19 / - | YO6MP | - / - | 2 | Partial capture |
| 09-15 06:17 | 40m | -14 / -13 | RA6OD | -3 / - | 3 | ✓ Closing observed |
| 09-15 06:14 | 40m | -13 / -4 | R3KJF | -7 / - | 4 | ✓ Closing observed |
| 09-15 06:13 | 40m | -9 / -23 | EW2GI | -16 / -10 | 5 | ✓ Full exchange observed |
| 09-15 06:12 | 40m | -1 / -5 | YO4AAC | -13 / -10 | 5 | ✓ Full exchange observed |
| 09-15 06:09 | 40m | -2 / - | EA6AJW | - / - | 2 | Partial capture |
| 09-15 05:59 | 40m | -3 / - | EH3ST | - / - | 3 | Partial capture |
| 09-15 05:57 | 40m | -2 / -12 | EU4U | -4 / -7 | 3 | ✓ Full exchange observed |
| 09-15 05:55 | 40m | -7 / - | YO2DSA | - / -9 | 5 | ✓ Closing fragment |
| 09-15 05:47 | 40m | -4 / - | R6HV/P | - / -9 | 2 | Partial capture |
| 09-15 05:45 | 40m | -4 / - | LZ2II | -3 / -6 | 5 | ✓ Full exchange observed |
| 09-15 05:44 | 40m | -2 / - | R6HV/P | - / -5 | 2 | Partial capture |
| 09-14 05:31 | 40m | -12 / - | CR7BRV | - / -15 | 2 | ✓ Closing fragment |
| 09-14 05:26 | 40m | -4 / - | IZ8PPI | - / -15 | 2 | ✓ Closing fragment |
| 09-14 05:24 | 40m | -10 / -19 | YO3GNF | -2 / -20 | 5 | ✓ Full exchange observed |
| 09-14 05:15 | 40m | -8 / - | SM7TZK | 0 / -15 | 3 | ✓ Closing observed |
| 09-14 05:10 | 40m | -9 / -5 | YT2FA | -19 / - | 3 | ✓ Closing observed |
| 09-14 05:10 | 40m | - / -17 | SM7TZK | -5 / - | 2 | Partial capture |
| 09-14 05:09 | 40m | -6 / -4 | SV1DKR | -7 / -10 | 4 | Partial capture |
| 09-14 05:06 | 40m | -10 / -15 | YL3GAO | -4 / - | 3 | ✓ Closing observed |
| 09-14 05:04 | 40m | -8 / - | YO2LGK | - / -3 | 2 | Partial capture |
| 09-14 05:03 | 40m | -2 / - | YO2LQF | - / -16 | 3 | ✓ Closing fragment |
| 09-14 04:59 | 40m | -7 / - | AB2E | - / - | 4 | Partial capture |
| 09-14 04:57 | 40m | -6 / - | 9A3MA | +4 / - | 2 | ✓ Closing observed |
| 09-14 04:55 | 40m | -8 / - | 9A3MA | - / - | 2 | Partial capture |
| 09-14 04:53 | 40m | - / - | SV1ENM | -14 / - | 2 | ✓ Closing fragment |
| 09-14 04:51 | 40m | +3 / -1 | DL8TV | +5 / - | 5 | ✓ Closing observed |
| 09-14 04:46 | 40m | - / -11 | OZ1KZX | -5 / - | 2 | ✓ Closing fragment |
| 09-14 04:44 | 40m | - / -7 | UA3LRN | -13 / - | 3 | ✓ Closing fragment |
| 09-14 04:42 | 40m | -8 / -12 | LA8ENA | +2 / - | 3 | ✓ Closing observed |
| 09-14 04:41 | 40m | -7 / - | OK1HEH | - / -15 | 2 | ✓ Closing fragment |
| 09-14 04:38 | 40m | -6 / - | YO7ZG | -4 / -8 | 3 | Partial capture |
| 09-14 04:37 | 40m | -8 / - | 4L7T | - / -14 | 3 | ✓ Closing fragment |
| 09-14 04:37 | 40m | -4 / -6 | ON1DGN | -14 / -11 | 7 | ✓ Full exchange observed |
| 09-14 04:35 | 40m | -6 / - | RW6MD/MM | - / -4 | 2 | Partial capture |
| 09-10 06:03 | 40m | - / - | UX2QX | -5 / - | 3 | Partial capture |
| 09-10 05:58 | 40m | -6 / -8 | ON4AOI | +1 / - | 3 | ✓ Closing observed |
| 09-10 05:58 | 40m | -5 / -9 | PA3CPS | +2 / - | 5 | ✓ Closing observed |
| 09-10 05:54 | 40m | -10 / - | US2YW | -15 / - | 2 | ✓ Closing observed |
| 09-10 05:54 | 40m | -6 / - | DH5BM | -1 / -19 | 3 | Partial capture |
| 09-10 05:49 | 40m | - / - | DK4RH | -6 / - | 2 | Partial capture |
| 09-10 05:40 | 40m | -12 / - | SO100PKP | - / -15 | 2 | Partial capture |
| 09-10 05:36 | 40m | -16 / - | VP5/K5UR | - / - | 2 | Partial capture |
| 09-10 05:32 | 40m | -19 / +2 | 9A4ZM | -17 / -5 | 5 | Partial capture |
| 09-10 05:32 | 40m | -16 / - | YO5PSE | - / -6 | 2 | ✓ Closing fragment |
| 09-10 05:31 | 40m | -20 / - | UR9QQ | -14 / -14 | 5 | ✓ Closing observed |
| 09-10 05:30 | 40m | -17 / -4 | YO6LM | -7 / -2 | 3 | ✓ Full exchange observed |
| 09-10 05:27 | 40m | -21 / -8 | RC2Y | -5 / - | 4 | ✓ Closing observed |
| 09-10 05:26 | 40m | - / -3 | SV2JAO | -2 / - | 3 | ✓ Closing fragment |
Recent FT8 messages decoded at SO8OO
Frequency values are decoder audio offsets in hertz, not RF frequencies.
UTC dB Audio Message 061445 -20 2281 YO4SX EW2GI RR73 061500 -14 2281 EW2GI YO4SX 73 061545 -7 2224 YO4SX R3KJF R-04 061600 -13 2281 R3KJF YO4SX RR73 061615 -8 2224 YO4SX R3KJF 73 061700 -14 2281 UA4FKT YO4SX RR73 061745 -4 2282 YO4SX RA6OD R-13 061800 -14 2281 RA6OD YO4SX RR73 061815 -2 2281 YO4SX RA6OD 73 062000 -19 2281 YO6MP YO4SX KN44 (x2) 062130 -18 2282 OK1AY YO4SX KN44 (x2) 062215 +3 2174 YO4SX OK1AY -04 062330 -23 2281 OK1AY YO4SX RR73
UTC dB Audio Message 053130 -7 1829 VK3YW YO4SX KN44 053200 -2 2318 F5DAN YO4SX KN44 (x2) 053330 -16 1740 ZY7F YO4SX KN44 (x4) 055930 +1 2244 VK2AJB YO4SX KN44 (x2) 060100 -7 2244 VK3EVE YO4SX KN44 045200 +7 1217 YO4SX UB4FGK -06 055530 -12 1033 YO4SX IZ8EYN +04 (x2) 060015 +1 2967 YO4SX IW5ALZ JN53 (x2)
UTC dB Audio Message 084615 -10 940 YO4SX DL8NW RR73 084630 -19 2228 DL8NW YO4SX 73 085245 -19 2228 RC5F YO4SX KN44 073245 -13 1970 YO4SX R7DX -01 073545 -21 1404 YO4SX YO4BXX -03 073615 -18 2232 YO4SX UG5F -06 123630 -17 2036 DC7KM YO4SX KN44 (x2) 124100 -22 2037 CQ YO4SX KN44 124115 -4 2664 YO4SX PD9FLX JO22 124145 -9 2675 YO4SX DO9QC JN58 125215 -13 1478 YO4SX LY3GY RR73 064230 -14 1450 YO4SX A71UN -11 (x3)
UTC dB Audio Message 022100 +24 2676 YO4SX SP6JIU RR73 022115 +22 2955 SP6JIU YO4SX 73 022145 +21 2955 SP3SLA YO4SX KN44 022230 +5 2955 YO3OBB YO4SX KN44 022245 +8 1448 YO4SX YO3OBB +22 022300 +6 2955 YO3OBB YO4SX R-16 022315 +13 1448 YO4SX YO3OBB RR73 022345 +1 2956 YO4SX UA4FKT LO23 022400 +5 2955 RY6O YO4SX KN44 (x2) 022545 +26 2955 EW8AAC YO4SX KN44 022600 -18 1223 YO4SX EW8AAC -09 022615 +26 2955 EW8AAC YO4SX KN44 022630 -18 1224 YO4SX EW8AAC -06 (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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