ON7UDM — FT8 activity observed at SO8OO

DXCC entity inferred from callsign: Belgium Most frequent locator attributed to this token: JO21

Receiver-side FT8 activity involving ON7UDM, decoded by SO8OO in southeastern Poland. 27 FT8 messages attributed to this token as transmitter, on 20m, across 1 UTC dates in the available aggregate history. Last observed 2026-07-21.

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 27 FT8 messages attributed to ON7UDM as the transmitting token by decoded message structure across 1 UTC dates in the available aggregate history. The largest monitored-band total was 20 m (100%). In this small sample, the estimated median decoder S/N was -14 dB; no usual signal pattern is inferred.

Overview

27
Messages attributed
1
UTC dates decoded
3
Active 15-min windows
-14 dB
Estimated median S/N

Bands

First attributed message: 2026-07-21
Last attributed message: 2026-07-21 12:58 UTC

Observed FT8 message patterns

Attributed sample
27 messages
Active dates
1 UTC dates
Estimated median S/N
-14 dB
Estimated 10th-90th percentile
-16 to -11 dB
Recurring-pattern threshold
Not met

SO8OO display ranges among successful decodes: weak (≤ -16 dB) 4, moderate (-15 to -9 dB) 23, strong (≥ -8 dB) 0.

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).

Most frequent locator attributed to ON7UDM

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
JO21 · 8 decoded messages
SO8OO receiver locator
KN09VW
Locator-centre separation
1,192 km (approx.)
Last such locator decoded
2026-07-21 12:58 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 UTCBandON7UDM S/NCounterpartCounterpart S/NMsgsCapture
07-21 09:13 20m -12 / - R4IK - / -14 2 ✓ Closing fragment
07-21 09:13 20m - / - RA6OV -4 / - 2 Partial capture
07-21 09:12 20m - / -15 R4FDW -19 / - 5 Partial capture
07-21 09:06 20m -12 / - F1PPH - / +1 2 ✓ Closing fragment
07-21 09:01 20m - / +4 GJ0KYZ -17 / - 3 Partial capture
07-21 09:01 20m -15 / - PD3LKN -15 / -21 9 Partial capture
07-21 08:58 20m -12 / - DG6TOM - / +6 2 ✓ Closing fragment
07-21 08:58 20m -15 / - 9A5AGN -18 / - 3 ✓ Closing observed
07-21 08:58 20m - / - PD3LKN -9 / - 3 Partial capture
07-21 08:56 20m -13 / - M7VME - / -25 2 ✓ Closing fragment
07-21 08:51 20m -16 / - DL9YNG - / +8 2 ✓ Closing fragment
07-21 08:50 20m -15 / +2 DL9UXF -10 / - 2 ✓ Closing observed

Recent FT8 messages decoded at SO8OO

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

20m
UTC    dB Audio  Message
090645 -10  831  F1PPH ON7UDM RR73
090715 -12  831  CQ ON7UDM JO21
090845 -18  831  F4BJN ON7UDM RR73
090945 -17  832  CQ ON7UDM JO21
091200 -18 1598  ON7UDM R4FDW -15 (x3)
091315 -14  831  CQ ON7UDM JO21
091330  -5  831  ON7UDM RA6OV KN87
091330 -17 1599  ON7UDM R4FDW -15
091345 -14  832  R4IK ON7UDM R-14
091400  -4  831  ON7UDM RA6OV KN87
091400 -23 1599  ON7UDM R4FDW -15
091415 -11  831  R4IK ON7UDM 73
125845 -13  834  CQ ON7UDM JO21

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