S51DD — FT8 activity observed at SO8OO
Receiver-side FT8 activity involving S51DD, decoded by SO8OO in southeastern Poland. 2,175 FT8 messages attributed to this token as transmitter, on 40m, 20m, 10m, across 29 UTC dates in the available aggregate history. Observed between 2026-06-06 and 2026-08-27.
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 2,175 FT8 messages attributed to S51DD as the transmitting token by decoded message structure across 29 UTC dates in the available aggregate history. The largest monitored-band total was 20 m (49%), followed by 40 m (44%) and 10 m (7%). Most decodes (53%) fell within the six-hour window 13:00-19:00 UTC. Most successfully decoded messages attributed to this token fell in SO8OO's strong S/N range (64%); the estimated median was -4 dB.
Overview
Bands
Last attributed message: 2026-08-27 07:56 UTC
Observed FT8 message patterns
- Attributed sample
- 2,175 messages
- Active dates
- 29 UTC dates
- Estimated median S/N
- -4 dB
- Estimated 10th-90th percentile
- -17 to +6 dB
- Recurring-pattern threshold
- Met
SO8OO display ranges among successful decodes: weak (≤ -16 dB) 298, moderate (-15 to -9 dB) 485, strong (≥ -8 dB) 1,392.
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 S51DD 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 S51DD
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
- JN76 · 1,286 decoded messages
- SO8OO receiver locator
- KN09VW
- Locator-centre separation
- 631 km (approx.)
- Last such locator decoded
- 2026-08-27 07:56 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 | S51DD S/N | Counterpart | Counterpart S/N | Msgs | Capture |
|---|---|---|---|---|---|---|
| 08-27 08:16 | 20m | - / - | OE3EHS | -23 / - | 4 | Partial capture |
| 08-27 07:56 | 20m | - / - | G4CFS | 0 / - | 2 | Partial capture |
| 08-27 07:50 | 20m | 0 / - | LZ1BT | - / +10 | 3 | ✓ Closing fragment |
| 08-27 07:48 | 20m | +10 / - | KA2H | - / -6 | 2 | ✓ Closing fragment |
| 08-27 07:47 | 20m | +5 / - | F4EKV | - / -19 | 2 | ✓ Closing fragment |
| 08-27 07:44 | 20m | +9 / - | IQ4JO | +8 / -20 | 3 | ✓ Closing observed |
| 08-27 07:42 | 20m | +14 / - | MI7RDK | - / -24 | 2 | Partial capture |
| 08-27 07:33 | 20m | +15 / - | RI1FJL | - / -8 | 11 | Partial capture |
| 08-21 19:07 | 10m | -22 / - | CD3GSC | - / - | 3 | Partial capture |
| 08-21 19:01 | 10m | -20 / - | ZA5G | - / - | 2 | Partial capture |
| 08-21 08:20 | 10m | - / - | TA6B | -15 / - | 2 | Partial capture |
| 08-18 08:48 | 10m | - / - | DN9SIB | -15 / - | 12 | Partial capture |
| 08-17 18:05 | 10m | - / - | LZ2EW | -13 / - | 20 | Partial capture |
| 08-17 17:57 | 10m | - / - | LZ2EW | -13 / - | 5 | Partial capture |
| 08-14 11:23 | 10m | - / +3 | 7Z1XX | -9 / - | 3 | ✓ Closing fragment |
| 08-14 11:17 | 10m | - / -12 | IU6CWS | -14 / - | 2 | Partial capture |
| 08-11 06:32 | 10m | - / - | F5THL | -16 / - | 2 | Partial capture |
| 08-09 18:40 | 10m | - / -8 | HB9CCM | -19 / - | 3 | ✓ Closing fragment |
| 08-09 18:06 | 10m | - / -1 | IV3APH | -10 / - | 4 | ✓ Closing fragment |
| 08-05 08:12 | 10m | - / +2 | R50RKZ | -4 / - | 2 | ✓ Closing fragment |
| 07-30 18:25 | 10m | - / -15 | OZ5AGJ | -18 / - | 4 | ✓ Closing fragment |
| 07-29 18:23 | 10m | - / +2 | SV8DCW | -8 / - | 2 | ✓ Closing fragment |
| 07-25 08:36 | 10m | - / -18 | F1PBZ | -7 / - | 2 | Partial capture |
| 07-24 08:31 | 10m | - / -3 | RG6S | -18 / - | 2 | ✓ Closing fragment |
| 07-23 07:27 | 40m | -15 / - | OS4K | - / -13 | 3 | Partial capture |
| 07-23 07:24 | 40m | -16 / - | ON3JDK | - / -16 | 2 | ✓ Closing fragment |
| 07-23 07:23 | 40m | -16 / - | EC3A | - / -11 | 2 | ✓ Closing fragment |
| 07-22 10:51 | 20m | -5 / - | TF5B | - / - | 3 | Partial capture |
| 07-22 10:46 | 20m | -3 / -16 | CN2DX | -23 / - | 2 | Partial capture |
| 07-22 09:06 | 10m | -17 / - | PD0GIP | - / -22 | 6 | ✓ Closing fragment |
| 07-22 09:04 | 10m | -17 / - | DN9BT | - / -5 | 2 | ✓ Closing fragment |
| 07-22 09:03 | 10m | -18 / -18 | DL3BH | -18 / - | 4 | ✓ Closing observed |
| 07-22 09:01 | 10m | -14 / - | UR3QRP | - / -4 | 2 | ✓ Closing fragment |
| 07-22 09:00 | 10m | -7 / - | DK3AE | - / -15 | 2 | ✓ Closing fragment |
| 07-22 08:59 | 10m | -14 / - | DJ8TX/P | - / -10 | 2 | ✓ Closing fragment |
| 07-22 08:57 | 10m | -14 / - | SM6FZO | - / -4 | 2 | ✓ Closing fragment |
| 07-22 08:56 | 10m | -16 / - | SP8MO | -23 / -5 | 3 | ✓ Closing observed |
| 07-22 08:49 | 10m | -17 / - | UT1US | 0 / - | 2 | Partial capture |
| 07-22 08:45 | 10m | -14 / - | IU0PXM | - / -1 | 2 | ✓ Closing fragment |
| 07-22 08:08 | 10m | - / - | DL8WEM | -4 / - | 3 | ✓ Closing fragment |
| 07-22 07:51 | 40m | -19 / - | DL3BH | - / -6 | 2 | ✓ Closing fragment |
| 07-22 07:48 | 40m | -17 / - | DK7JR | - / +7 | 2 | ✓ Closing fragment |
| 07-22 07:38 | 40m | -23 / - | UA4FKT | - / -7 | 3 | Partial capture |
| 07-22 07:37 | 40m | -24 / - | SM6FZO | - / -3 | 2 | ✓ Closing fragment |
| 07-22 07:32 | 40m | -22 / - | C31KC | - / -5 | 2 | Partial capture |
| 07-22 07:31 | 40m | -22 / - | DH3KR | -18 / -2 | 3 | ✓ Closing observed |
| 07-22 07:29 | 40m | -21 / - | PA7D | - / -11 | 2 | ✓ Closing fragment |
| 07-21 14:07 | 10m | - / - | UB3BCT | -18 / - | 2 | ✓ Closing fragment |
| 07-21 13:47 | 10m | -3 / - | TK5K | - / - | 4 | Partial capture |
| 07-21 13:45 | 10m | -6 / - | SV9MBH | - / - | 3 | Partial capture |
Recent FT8 messages decoded at SO8OO
Frequency values are decoder audio offsets in hertz, not RF frequencies.
UTC dB Audio Message 075245 -4 2185 CQ S51DD JN76 (x7) 075600 +2 2777 S51DD G4CFS IO91 075615 +11 2187 CQ S51DD JN76 075630 -1 2777 S51DD G4CFS IO91 075645 +8 2187 CQ S51DD JN76 081600 -24 2310 S51DD OE3EHS JN87 (x4)
UTC dB Audio Message 081730 -12 731 S51DD R7RAG RR73 082000 -18 1787 S51DD TA6B KN81 (x2) 185345 -15 2322 LU2FRP S51DD R-09 185515 -17 2322 CQ S51DD JN76 (x3) 185945 -13 2323 SM0JHB S51DD -09 190145 -19 2322 ZA5G S51DD JN76 (x2) 190645 -22 2076 ZV8R S51DD R-15 190745 -22 2074 CD3GSC S51DD JN76 (x3) 191600 -23 2089 LU1EEP S51DD JN76
UTC dB Audio Message 075945 -17 1956 CQ S51DD JN76 (x3) 072345 -19 1960 EC3A S51DD R-11 (x2) 072445 -16 1959 ON3JDK S51DD -16 072615 -15 1959 DG6TOM S51DD RR73 072645 -16 1958 ON3JDK S51DD RR73 072715 -15 1958 CQ S51DD JN76 072745 -15 2028 OS4K S51DD R-13 (x3) 073115 -22 2027 F4AWT S51DD RR73 073315 -21 2027 CQ S51DD JN76 (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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