S51SU — FT8 activity observed at SO8OO

DXCC entity inferred from callsign: Slovenia Most frequent locator attributed to this token: JN76

Receiver-side FT8 activity involving S51SU, decoded by SO8OO in southeastern Poland. 154 FT8 messages attributed to this token as transmitter, on 80m, 60m, 20m, across 14 UTC dates in the available aggregate history. Observed between 2026-06-17 and 2026-09-01.

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 154 FT8 messages attributed to S51SU as the transmitting token by decoded message structure across 14 UTC dates in the available aggregate history. The largest monitored-band total was 80 m (69%), followed by 60 m (18%) and 20 m (13%). Several six-hour UTC windows tied for the largest share (74%), so no unique busiest interval is claimed. Received S/N was mixed across SO8OO's weak, moderate and strong ranges; the estimated median was -8 dB.

Overview

154
Messages attributed
14
UTC dates decoded
24
Active 15-min windows
-8 dB
Estimated median S/N

Bands

80m · 107 60m · 27 20m · 20
First attributed message: 2026-06-17
Last attributed message: 2026-09-01 20:07 UTC

Observed FT8 message patterns

Attributed sample
154 messages
Active dates
14 UTC dates
Estimated median S/N
-8 dB
Estimated 10th-90th percentile
-19 to +4 dB
Recurring-pattern threshold
Met

SO8OO display ranges among successful decodes: weak (≤ -16 dB) 20, moderate (-15 to -9 dB) 51, strong (≥ -8 dB) 83.

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 S51SU 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 S51SU

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 · 59 decoded messages
SO8OO receiver locator
KN09VW
Locator-centre separation
631 km (approx.)
Last such locator decoded
2026-09-01 20:06 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 UTCBandS51SU S/NCounterpartCounterpart S/NMsgsCapture
08-27 03:39 80m - / -15 DO1BOC -1 / - 16 Partial capture
08-27 03:33 80m -1 / -6 EC5M -14 / +1 5 ✓ Full exchange observed
08-27 03:31 80m +6 / -10 F5MYK -20 / -11 5 ✓ Full exchange observed
08-27 03:30 80m -6 / -5 YO8RAW -4 / 0 5 ✓ Full exchange observed
08-27 03:24 60m -9 / +3 SV8MQP +8 / - 7 ✓ Full exchange observed
08-27 03:21 60m -9 / -13 G8UBJ -11 / +3 4 ✓ Full exchange observed
08-27 03:19 60m -11 / +1 LZ2JE +14 / - 5 ✓ Full exchange observed
08-27 03:18 80m +6 / - CT2HEX - / - 2 Partial capture
08-27 03:17 80m - / -1 ES2AJ -6 / - 4 Partial capture
08-27 03:13 80m -8 / - DL1YFS -19 / -6 6 Partial capture
08-27 03:13 80m -4 / - ES2AJ 0 / -2 3 Partial capture
08-27 03:13 80m -7 / -11 UT5MB -5 / -13 9 ✓ Full exchange observed
08-27 03:10 80m -6 / - W3LL - / - 2 Partial capture
08-27 03:10 80m -2 / +1 DL7FE -14 / -5 6 ✓ Full exchange observed
08-27 03:08 80m -14 / -15 HF5A -6 / -14 5 ✓ Full exchange observed
08-27 03:06 80m -12 / - CT2HEX - / - 3 Partial capture
08-27 03:02 80m +2 / -1 OK1HEH +2 / -12 6 ✓ Full exchange observed
08-27 03:02 80m +6 / -2 YU7YZ +21 / - 3 ✓ Closing observed
08-27 02:59 80m -1 / -21 DO1FFO -7 / -10 9 ✓ Full exchange observed
08-27 02:57 80m -9 / - DL1UDO - / - 2 Partial capture
08-27 02:55 80m -6 / -6 SN40KZE +11 / - 3 Partial capture
08-25 02:11 80m -1 / -7 MM0KQC -2 / - 3 Partial capture
08-25 02:09 80m +2 / -4 DL9KM -1 / - 4 ✓ Closing observed
08-25 02:06 80m -4 / -12 MM0KQC -6 / -4 6 ✓ Full exchange observed
08-25 02:06 80m -2 / -11 UA4FKT +9 / +6 6 ✓ Full exchange observed
08-25 02:05 80m -5 / -5 9A5MP -4 / -8 5 ✓ Full exchange observed
08-21 13:26 20m -12 / - OH1LA - / -22 4 Partial capture
08-21 13:25 20m - / -6 9A5RIS -12 / - 3 ✓ Closing fragment
08-21 13:21 20m -8 / - PA0ARR - / -11 2 ✓ Closing fragment
08-21 13:18 20m - / -18 PD1ADA +1 / - 4 ✓ Closing fragment
08-21 13:17 20m - / -20 UT7UJ +3 / - 3 ✓ Closing fragment
08-21 13:15 20m - / -19 PC2J +4 / - 3 ✓ Closing fragment
08-20 13:55 20m - / - DL3BH -16 / - 2 ✓ Closing fragment
08-20 13:52 20m - / -8 UT4QM -15 / - 2 ✓ Closing fragment
08-20 13:50 20m - / -9 PA1PXL -11 / - 4 Partial capture
08-20 13:47 20m - / -16 PD3LKN -6 / - 2 ✓ Closing fragment
08-16 18:58 80m -6 / -20 ES6DO -12 / -20 4 ✓ Full exchange observed
08-16 18:52 80m -16 / -17 DO9KB +8 / - 4 ✓ Closing observed
08-16 18:46 80m -8 / -3 IZ7NLJ -8 / -1 5 ✓ Full exchange observed
08-16 18:44 80m -8 / -7 SQ2BXI +19 / +8 5 ✓ Full exchange observed
08-16 18:40 80m -4 / -21 PB1PCH -14 / -12 8 ✓ Full exchange observed
08-15 15:00 20m -13 / - A61CK - / - 3 Partial capture
07-21 13:00 20m - / -16 DL1UDO -10 / - 8 ✓ Closing fragment
07-21 12:55 20m - / - F4HSB -18 / - 2 Partial capture
07-21 12:52 20m - / 0 HG8LXL 0 / - 3 ✓ Closing fragment
07-08 01:23 80m -4 / - A71UN - / - 2 Partial capture
07-08 01:21 80m +6 / -12 EA5HM -16 / -5 6 ✓ Full exchange observed
07-08 01:19 80m +5 / -1 DL9ATW -6 / -3 6 ✓ Full exchange observed
07-08 01:16 80m +8 / - A71UN -7 / -6 5 Partial capture
07-08 01:16 80m +4 / -7 SP9JMZ +12 / -4 5 ✓ Full exchange observed

Recent FT8 messages decoded at SO8OO

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

80m 
UTC    dB Audio  Message
034230  +0  615  S51SU DO1BOC -15 (x11)
200500  -2 1335  CQ S51SU JN76                         a1 (x3)
200730  -6 1335  HB3XGP S51SU -01
60m 
UTC    dB Audio  Message
032000 +13 1031  S51SU LZ2JE +01
032015  -9 1031  LZ2JE S51SU R+16
032030 +14 1031  S51SU LZ2JE RR73
032045 -11 1031  LZ2JE S51SU 73
032130 -10  777  G8UBJ S51SU JN76
032145 -11  777  S51SU G8UBJ -13
032200 -10  776  G8UBJ S51SU R+03 (x2)
032445 -10 2490  SV8MQP S51SU JN76 (x2)
032530  +5 2490  S51SU SV8MQP +03
032545  -7 2490  SV8MQP S51SU R+14
032600  +8 2490  S51SU SV8MQP RR73
032615  -9 2490  SV8MQP S51SU 73
032630 +12 2490  S51SU SV8MQP -08
20m 
UTC    dB Audio  Message
131915  +3 2034  S51SU PD1ADA JO21 (x3)
132130 -10 1643  PA0ARR S51SU R-11 (x2)
132230 -10 1642  CQ S51SU JN76                         a1
132300  -8 1643  IU8UHK S51SU -09
132500 -11 1643  CQ S51SU JN76
132515  -7 1643  S51SU 9A5RIS JN74 (x2)
132630 -12 1643  OH1LA S51SU -22
132645 -13 1643  S51SU 9A5RIS RR73
132700 -11 1643  OH1LA S51SU -22 (x3)

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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