S51DX — FT8 activity observed at SO8OO
Receiver-side FT8 activity involving S51DX, decoded by SO8OO in southeastern Poland. 31 FT8 messages attributed to this token as transmitter, on 60m, 20m, across 3 UTC dates in the available aggregate history. Observed between 2026-06-10 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 31 FT8 messages attributed to S51DX as the transmitting token by decoded message structure across 3 UTC dates in the available aggregate history. The largest monitored-band total was 20 m (52%), followed by 60 m (48%). In this small sample, the estimated median decoder S/N was +5 dB; no usual signal pattern is inferred.
Overview
Bands
Last attributed message: 2026-09-15 01:52 UTC
Observed FT8 message patterns
- Attributed sample
- 31 messages
- Active dates
- 3 UTC dates
- Estimated median S/N
- +5 dB
- Estimated 10th-90th percentile
- -17 to +8 dB
- Recurring-pattern threshold
- Not met
SO8OO display ranges among successful decodes: weak (≤ -16 dB) 5, moderate (-15 to -9 dB) 7, strong (≥ -8 dB) 19.
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. The sample does not meet the threshold for a recurring time or signal-pattern claim (20 attributed messages, three UTC dates and five distinct 15-minute windows).
Frequent counterpart tokens observed at SO8OO
Tokens most often paired with S51DX in decoded directed-looking exchanges:
Most frequent locator attributed to S51DX
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
- JN75 · 20 decoded messages
- SO8OO receiver locator
- KN09VW
- Locator-centre separation
- 708 km (approx.)
- Last such locator decoded
- 2026-09-15 01:52 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 | S51DX S/N | Counterpart | Counterpart S/N | Msgs | Capture |
|---|---|---|---|---|---|---|
| 09-15 01:50 | 60m | -18 / -7 | UR9QQ | -4 / -8 | 5 | ✓ Full exchange observed |
| 09-15 01:48 | 60m | -14 / - | 8R1TM | - / -8 | 4 | ✓ Closing fragment |
| 07-17 18:53 | 20m | +7 / - | TN8GD | - / - | 4 | Partial capture |
| 07-17 18:52 | 20m | +8 / - | OK2VCR | - / +2 | 2 | ✓ Closing fragment |
| 07-17 18:51 | 20m | +8 / +7 | R4FDW | -16 / -13 | 4 | ✓ Full exchange observed |
| 07-17 18:49 | 20m | +5 / - | <...> | - / +5 | 2 | Partial capture |
| 07-17 18:46 | 20m | +8 / - | 3W9A | - / +2 | 6 | ✓ Closing fragment |
Recent FT8 messages decoded at SO8OO
Frequency values are decoder audio offsets in hertz, not RF frequencies.
UTC dB Audio Message 014845 -17 1654 8R1TM S51DX JN75 (x4) 015030 -4 1835 S51DX UR9QQ KN77 015045 -18 1309 UR9QQ S51DX -08 015100 -3 1835 S51DX UR9QQ R-07 015115 -18 1309 UR9QQ S51DX RR73 015130 -4 1835 S51DX UR9QQ 73 015145 -18 1309 CQ S51DX JN75 (x2)
UTC dB Audio Message 184745 +11 1678 3W9A S51DX JN75 (x3) 184915 +5 1678 <...> S51DX JN75 (x2) 185100 -15 1199 S51DX R4FDW +07 185145 +7 1678 R4FDW S51DX R-13 185200 -18 1199 S51DX R4FDW RR73 185215 +8 1678 R4FDW S51DX 73 185245 +10 1678 OK2VCR S51DX +02 (x2) 185345 +7 1678 TN8GD S51DX JN75 (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.
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CW beta — S51DX
2 confirmed CW reception events in the last 30 days. CW and FT8 statistics are counted separately.
CW reception history