ON4ARJ — FT8 activity observed at SO8OO

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

Receiver-side FT8 activity involving ON4ARJ, decoded by SO8OO in southeastern Poland. 16 FT8 messages attributed to this token as transmitter, on 80m, 60m, 40m, 10m, across 4 UTC dates in the available aggregate history. Observed between 2026-07-02 and 2026-08-08.

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 16 FT8 messages attributed to ON4ARJ as the transmitting token by decoded message structure across 4 UTC dates in the available aggregate history. The largest monitored-band total was 60 m (63%), followed by 40 m (19%) and 10 m (13%). In this small sample, the estimated median decoder S/N was -8 dB; no usual signal pattern is inferred.

Overview

16
Messages attributed
4
UTC dates decoded
5
Active 15-min windows
-8 dB
Estimated median S/N

Bands

First attributed message: 2026-07-02
Last attributed message: 2026-08-08 03:04 UTC

Observed FT8 message patterns

Attributed sample
16 messages
Active dates
4 UTC dates
Estimated median S/N
-8 dB
S/N percentile sample
Too small
Recurring-pattern threshold
Not met

SO8OO display ranges among successful decodes: weak (≤ -16 dB) 4, moderate (-15 to -9 dB) 3, strong (≥ -8 dB) 9.

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 ON4ARJ in decoded directed-looking exchanges:

Most frequent locator attributed to ON4ARJ

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 · 5 decoded messages
SO8OO receiver locator
KN09VW
Locator-centre separation
1,192 km (approx.)
Last such locator decoded
2026-08-08 03:03 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 UTCBandON4ARJ S/NCounterpartCounterpart S/NMsgsCapture
08-08 03:03 40m -8 / - OA4ENG - / -9 3 ✓ Closing fragment
07-29 18:49 10m -20 / - Z61DX - / - 2 Partial capture
07-02 21:16 60m -4 / -9 DL9KM -16 / -12 6 ✓ Full exchange observed
07-02 21:15 60m -11 / -3 OT4R -9 / +5 3 Partial capture
07-02 21:12 60m -7 / -8 HB9EKJ -10 / -5 6 ✓ Full exchange observed
07-02 21:12 60m -9 / - GW8CRH - / +1 3 ✓ Closing fragment

Recent FT8 messages decoded at SO8OO

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

40m
UTC    dB Audio  Message
030300  -9 2512  OA4ENG ON4ARJ JO21 (x3)
10m
UTC    dB Audio  Message
184900 -18 1472  Z61DX ON4ARJ JO21 (x2)
80m
UTC    dB Audio  Message
214645 -13 1321  TN8GD ON4ARJ JO21
60m
UTC    dB Audio  Message
211330  -7 1004  HB9EKJ ON4ARJ -05
211345  -7  252  ON4ARJ HB9EKJ R-08
211400  -7 1005  HB9EKJ ON4ARJ RR73
211415  -9  252  ON4ARJ HB9EKJ 73
211530 -18 1004  <...> ON4ARJ R+07
211545  -9 1392  ON4ARJ OT4R -03
211545 -19 1875  <ON4ARJ> DP75BAC RR73
211615 -19 1320  ON4ARJ DL9KM JN68
211630 -16 1004  OT4R ON4ARJ R+05
211645 -16 1320  ON4ARJ DL9KM JN68
211700  -6 1004  OT4R ON4ARJ R+05
211730  -8 1004  DL9KM ON4ARJ -12
211745 -16 1320  ON4ARJ DL9KM R-09
211800  -1  504  DL9KM ON4ARJ RR73
211815 -15 1320  ON4ARJ DL9KM 73

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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