OS5U — FT8 activity observed at SO8OO

DXCC entity inferred from callsign: Belgium Most frequent locator attributed to this token: JO10

Receiver-side FT8 activity involving OS5U, decoded by SO8OO in southeastern Poland. 53 FT8 messages attributed to this token as transmitter, on 40m, 20m, across 7 UTC dates in the available aggregate history. Observed between 2026-06-23 and 2026-09-05.

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 53 FT8 messages attributed to OS5U as the transmitting token by decoded message structure across 7 UTC dates in the available aggregate history. The largest monitored-band total was 20 m (98%), followed by 40 m (2%). Most decodes (92%) fell within the six-hour window 08:00-14:00 UTC. Received S/N was mixed across SO8OO's weak, moderate and strong ranges; the estimated median was -10 dB.

Overview

53
Messages attributed
7
UTC dates decoded
11
Active 15-min windows
-10 dB
Estimated median S/N

Bands

40m · 1 20m · 52
First attributed message: 2026-06-23
Last attributed message: 2026-09-05 07:46 UTC

Observed FT8 message patterns

Attributed sample
53 messages
Active dates
7 UTC dates
Estimated median S/N
-10 dB
Estimated 10th-90th percentile
-17 to -1 dB
Recurring-pattern threshold
Met

SO8OO display ranges among successful decodes: weak (≤ -16 dB) 12, moderate (-15 to -9 dB) 21, strong (≥ -8 dB) 20.

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 OS5U 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 OS5U

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
JO10 · 32 decoded messages
SO8OO receiver locator
KN09VW
Locator-centre separation
1,335 km (approx.)
Last such locator decoded
2026-09-05 07:46 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 UTCBandOS5U S/NCounterpartCounterpart S/NMsgsCapture
09-19 13:45 40m - / -8 DA2JM -17 / - 2 Partial capture
09-13 14:32 40m - / -7 PA3BMB -12 / - 3 ✓ Closing fragment
09-13 14:26 40m - / - HG8LXL -4 / - 4 Partial capture
09-13 14:24 40m - / -3 DL6EL +3 / - 4 ✓ Closing fragment
09-13 10:16 40m - / -19 I4BUQ -19 / - 3 Partial capture
09-13 10:09 40m - / - HG8LXL -8 / - 4 Partial capture
09-13 10:01 40m - / -3 DL8LSK -7 / - 3 ✓ Closing fragment
09-13 09:55 40m - / - HG8LXL -8 / - 2 Partial capture
09-13 09:45 40m - / -8 DL3LBK -19 / - 3 ✓ Closing fragment
09-13 08:51 40m - / - HG8LXL -6 / - 4 Partial capture
09-06 14:09 40m - / -15 OK1XQ +2 / - 4 Partial capture
09-06 14:07 40m - / - PA3AGN -18 / - 2 ✓ Closing fragment
09-06 14:06 40m - / -12 SQ9PBV +6 / - 3 ✓ Closing fragment
09-06 14:04 40m - / -5 DF2US -12 / - 3 ✓ Closing fragment
09-06 13:57 40m - / - DK3HJ -14 / - 3 Partial capture
09-06 13:53 40m - / -7 DL1IP -14 / - 3 ✓ Closing fragment
09-06 10:11 40m - / -4 PD0IFI -14 / - 5 ✓ Closing fragment
09-06 10:10 40m - / -5 DL9KM -12 / - 3 Partial capture
09-06 09:56 40m - / +4 PA3GAE -12 / - 4 ✓ Closing fragment
09-06 09:56 40m - / - PD0IFI -2 / - 2 Partial capture
09-06 09:55 40m - / - DJ1TU -18 / - 4 Partial capture
09-06 09:31 40m - / - PD0IFI -4 / - 3 Partial capture
09-06 09:19 40m - / - PE1NPS -16 / - 4 Partial capture
09-05 09:53 40m - / - ON5RZ -17 / - 3 Partial capture
09-05 09:46 40m - / - ON5RZ -17 / - 3 Partial capture
09-05 09:45 40m - / - SN4K -6 / - 2 Partial capture
09-05 09:20 40m - / -20 R2FEA -4 / - 2 Partial capture
09-05 08:56 40m - / - F4HHY -15 / - 2 ✓ Closing fragment
09-05 08:50 40m - / -11 OE2LEX -22 / - 2 Partial capture
09-05 08:42 40m - / - DL6REX -18 / - 3 ✓ Closing fragment
09-05 08:42 40m - / - DL9KM -7 / - 7 Partial capture
09-05 08:38 40m - / -10 DL1SRS -16 / - 3 ✓ Closing fragment
09-05 08:33 40m - / -11 F1PBZ -8 / - 2 Partial capture
09-05 07:39 40m - / -6 HA7TM -11 / - 3 ✓ Closing fragment
09-04 13:31 40m - / - DL1KYF/P -14 / - 2 Partial capture
08-30 12:58 40m - / -5 DL7ACA -13 / - 2 ✓ Closing fragment
08-30 08:41 20m -6 / - UA3AIU +7 / +4 3 ✓ Closing observed
08-30 08:39 20m -4 / -16 EA3IE -10 / -5 5 ✓ Full exchange observed
08-30 08:38 20m -5 / - DL6UM - / -14 2 ✓ Closing fragment
08-30 08:37 20m -6 / - UT7UJ - / +4 2 ✓ Closing fragment
08-30 08:34 20m -8 / -9 UA3VVA +7 / +4 5 ✓ Full exchange observed
08-29 19:01 20m - / -16 EC3A -2 / - 2 Partial capture
08-29 18:58 20m - / -6 IV3JRY -8 / - 5 ✓ Closing fragment
08-29 18:54 20m - / -20 EC3A -9 / - 4 Partial capture
08-29 08:39 20m -18 / -15 R4FDD -9 / -5 7 ✓ Full exchange observed
08-23 13:18 40m - / -18 9A3CX -7 / - 5 ✓ Closing fragment
08-22 09:28 40m - / -26 HG3FMZ -2 / - 4 ✓ Closing fragment
08-22 09:25 40m - / - DL7ARV +5 / - 6 Partial capture
08-22 09:23 40m - / -6 DD7EE -7 / - 3 ✓ Closing fragment
08-22 09:22 20m - / - DM5CF -6 / - 2 Partial capture

Recent FT8 messages decoded at SO8OO

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

40m 
UTC    dB Audio  Message
142430  +3  726  OS5U DL6EL JN57 (x3)
142600  -4 1647  OS5U HG8LXL KN06
142600  +6  726  OS5U DL6EL 73
142630  -4 1647  OS5U HG8LXL KN06 (x3)
143000  -9 2644  OS5U DK1XAM R-10
143200 -13 1225  OS5U PA3BMB JO22 (x3)
143600 -19 1225  OS5U DL1EFX 73
134500 -16 1224  OS5U DA2JM JN39 (x2)
20m 
UTC    dB Audio  Message
083915  +0 1247  DL6UM OS5U RR73
083930  -7 1084  OS5U EA3IE JN01
083945  -5 1247  EA3IE OS5U -05
084000 -11 1084  OS5U EA3IE R-16
084015  -3 1246  EA3IE OS5U RR73
084030 -11 1085  OS5U EA3IE 73
084045  -9 1246  CQ OS5U JO10
084100  +7 1248  OS5U UA3AIU KO85
084115  -9 1246  UA3AIU OS5U +04 (x2)
084245  +2 1246  CQ OS5U JO10 (x5)

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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