ON4APU — FT8 activity observed at SO8OO

DXCC entity inferred from callsign: Belgium Most frequent locator attributed to this token: JO11

Receiver-side FT8 activity involving ON4APU, decoded by SO8OO in southeastern Poland. 293 FT8 messages attributed to this token as transmitter, on 80m, 60m, 40m, 20m, 10m, across 24 UTC dates in the available aggregate history. Observed between 2026-06-06 and 2026-09-04.

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 293 FT8 messages attributed to ON4APU as the transmitting token by decoded message structure across 24 UTC dates in the available aggregate history. The largest monitored-band total was 20 m (48%), followed by 40 m (31%) and 80 m (14%). Most decodes (74%) fell within the six-hour window 15:00-21:00 UTC. Most successfully decoded messages attributed to this token fell in SO8OO's strong S/N range (68%); the estimated median was -3.1 dB.

Overview

293
Messages attributed
24
UTC dates decoded
61
Active 15-min windows
-3.1 dB
Estimated median S/N

Bands

First attributed message: 2026-06-06
Last attributed message: 2026-09-04 15:01 UTC

Observed FT8 message patterns

Attributed sample
293 messages
Active dates
24 UTC dates
Estimated median S/N
-3.1 dB
Estimated 10th-90th percentile
-15 to +12 dB
Recurring-pattern threshold
Met

SO8OO display ranges among successful decodes: weak (≤ -16 dB) 23, moderate (-15 to -9 dB) 72, strong (≥ -8 dB) 198.

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.

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 ON4APU

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
JO11 · 176 decoded messages
SO8OO receiver locator
KN09VW
Locator-centre separation
1,331 km (approx.)
Last such locator decoded
2026-09-04 15:01 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 UTCBandON4APU S/NCounterpartCounterpart S/NMsgsCapture
09-04 15:01 40m -6 / - <...> - / -13 2 Partial capture
09-03 19:25 80m -4 / - R3ZBY -10 / - 2 ✓ Closing observed
09-03 19:20 80m -11 / +1 R3YAU -1 / - 3 ✓ Closing observed
09-03 19:17 80m 0 / - <...> - / 0 3 Partial capture
09-03 19:14 80m 0 / -6 R6KX 0 / -11 6 ✓ Full exchange observed
09-03 19:11 80m - / +4 DK7TX -7 / - 2 ✓ Closing fragment
09-03 19:10 80m 0 / -17 <...> -6 / -5 6 Partial capture
09-02 18:08 40m +6 / -5 YO4NT +6 / -1 4 ✓ Full exchange observed
09-02 18:07 40m +4 / - SQ100PKP - / -8 2 Partial capture
09-02 18:04 40m -7 / 0 3Z100PKP -8 / -2 3 Partial capture
09-02 18:03 40m +4 / - EJ8JCB - / -7 2 ✓ Closing fragment
09-02 18:00 40m 0 / -21 EG42SDC -8 / - 6 Partial capture
09-02 17:59 40m -8 / - <...> - / - 2 Partial capture
08-29 19:29 80m - / -13 UR3HC +7 / - 2 Partial capture
08-29 19:29 80m - / -15 SP5FWT +2 / - 3 Partial capture
08-29 19:19 80m +4 / -4 SP9WAZ +3 / -5 5 ✓ Full exchange observed
08-29 19:18 80m +2 / -3 DO2BBC -2 / -5 4 ✓ Full exchange observed
08-29 19:15 80m -1 / - SP1905MFK - / -18 4 Partial capture
08-26 08:00 40m -14 / - ON6CQ - / - 4 Partial capture
08-26 07:48 40m -21 / -4 SN40KZE -12 / - 3 Partial capture
08-25 14:44 20m +8 / - <...> - / -10 4 Partial capture
08-21 20:24 80m -10 / -12 SV8TCK +11 / -8 6 Partial capture
08-21 20:22 80m -6 / +1 <...> -11 / -2 5 Partial capture
08-21 20:12 20m +2 / - BA8BLK - / -10 2 ✓ Closing fragment
08-21 20:10 20m +5 / - DS2MGT - / -15 2 ✓ Closing fragment
08-21 20:08 20m +12 / - UA0LQE - / -16 2 Partial capture
08-21 20:07 20m +15 / - BD6IIC - / -16 2 ✓ Closing fragment
08-21 20:06 20m +7 / - DL1R +11 / -17 10 Partial capture
08-21 19:51 20m +3 / - <...> - / -22 10 Partial capture
08-21 19:36 80m -8 / - <...> - / - 2 Partial capture
08-18 19:58 60m - / - YO6LM +8 / - 2 Partial capture
08-18 19:57 60m -6 / - <...> - / -7 2 Partial capture
08-15 18:48 20m +9 / - <...> - / - 2 Partial capture
08-10 16:08 20m 0 / - <...> - / -8 8 Partial capture
08-10 15:43 20m -1 / - <...> - / -11 2 Partial capture
08-10 15:39 20m 0 / - <...> - / -13 2 Partial capture
08-10 04:37 40m - / -19 EN35UKR -6 / - 2 Partial capture
08-06 19:37 60m -11 / - EA3RO - / -14 3 ✓ Closing fragment
08-06 19:33 60m 0 / - <...> - / 0 2 Partial capture
08-06 19:30 20m -1 / - <...> - / - 3 Partial capture
07-21 19:31 40m - / -1 E70SZ +3 / - 3 ✓ Closing fragment
07-21 19:28 40m -14 / -22 UX7QV -11 / -15 4 ✓ Full exchange observed
07-21 19:26 40m -12 / -7 YO4FRF -7 / -11 19 ✓ Full exchange observed
07-21 19:25 40m -6 / +7 DL3JHK -10 / - 3 ✓ Closing observed
07-21 19:23 40m -8 / -9 IQ4JO 0 / -11 4 ✓ Full exchange observed
07-21 19:18 40m -8 / -4 SQ3TR -11 / -14 5 ✓ Full exchange observed
07-21 19:16 40m -12 / - SV1TRJ - / -12 2 ✓ Closing fragment
07-21 19:16 40m -12 / -8 DK3TNA -18 / 0 6 ✓ Full exchange observed
07-21 19:13 40m -14 / - PD1LVK - / -10 2 ✓ Closing fragment
07-21 19:10 40m -16 / - DH5BM - / -9 2 ✓ Closing fragment

Recent FT8 messages decoded at SO8OO

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

40m
UTC    dB Audio  Message
180500  -6  535  ON4APU EG42SDC -05
180515  -6 1315  3Z100PKP ON4APU R-02
180700  +5  652  SQ100PKP ON4APU JO11
180715  -8 1295  ON4APU 3Z100PKP +00
180730  +3  652  SQ100PKP ON4APU R-08
180815  +8 2219  ON4APU YO4NT -05
180830  +5  653  YO4NT ON4APU R-01
180845  +4 2218  ON4APU YO4NT RR73
180900  +7  653  YO4NT ON4APU 73
101045 -18 1175  HF100PKP ON4APU JO11
101100  +9 1044  ON4APU SQ100PKP -01
101130  +7 1044  ON4APU RR73; HG0NPJ <...> +16
143730 -11  755  R2FBW ON4APU JO11
150115  -6  704  <...> ON4APU JO11 (x2)
80m
UTC    dB Audio  Message
191500  +2 2562  ON4APU R6KX RR73
191515  +4  799  R6KX ON4APU 73 (x3)
191715  +0  800  <...> ON4APU JO11 (x2)
191800 +15 2625  ON4APU SP100PKP +10
191815  -1  799  <...> ON4APU R+00
191830 +17 2625  ON4APU RR73; UR5TMT <...> -06
192000 -11  799  R3YAU ON4APU JO11
192015  +2 1733  ON4APU R3YAU +01 (x2)
192115 -12  226  ON4APU R3ZBY -10 (x2)
192530  -4  800  R3ZBY ON4APU 73
20m
UTC    dB Audio  Message
200915 +11 2656  ON4APU DL1R JN58
200930 +10  779  CQ ON4APU JO11
200945 +10 2656  ON4APU DL1R JN58
201000  +3  779  CQ ON4APU JO11
201015 +11 2656  ON4APU DL1R JN58
201015  +0  834  ON4APU DB9LG JO40
201030  +2  779  DS2MGT ON4APU R-15
201045 +12 2656  ON4APU DL1R JN58
201100  +8  779  DS2MGT ON4APU 73
201200  +4  779  BA8BLK ON4APU R-10 (x2)
144415 +14 2463  <...> ON4APU JO11 (x4)
60m
UTC    dB Audio  Message
193345  +0 2603  <...> ON4APU JO11
193400  +7  929  ON4APU HG25CCS -04
193415  -1 2603  <...> ON4APU R+00
193645 -10 1948  CQ ON4APU JO11
193715 -11 1948  EA3RO ON4APU -14 (x3)
193845 -13 1948  CQ ON4APU JO11
193930 -15  996  ON4APU OE5YCP JN68
195715  -5  825  <...> ON4APU JO11
195730 -11 2450  ON4APU DQ30GDXF -01
195745  -6  824  <...> ON4APU R-07
195830  +7 2514  ON4APU YO6LM KN25 (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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