AC4JU — FT8 activity observed at SO8OO
Receiver-side FT8 activity involving AC4JU, decoded by SO8OO in southeastern Poland. 111 FT8 messages attributed to this token as transmitter, on 20m, across 2 UTC dates in the available aggregate history. Observed between 2026-06-07 and 2026-06-08.
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 111 FT8 messages attributed to AC4JU as the transmitting token by decoded message structure across 2 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 -15 dB; no usual signal pattern is inferred.
Overview
Observed FT8 message patterns
- Attributed sample
- 111 messages
- Active dates
- 2 UTC dates
- Estimated median S/N
- -15 dB
- Estimated 10th-90th percentile
- -21 to -10 dB
- Recurring-pattern threshold
- Not met
SO8OO display ranges among successful decodes: weak (≤ -16 dB) 55, moderate (-15 to -9 dB) 54, strong (≥ -8 dB) 2.
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 AC4JU in decoded directed-looking exchanges:
Most frequent locator attributed to AC4JU
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
- EL98 · 10 decoded messages
- SO8OO receiver locator
- KN09VW
- Locator-centre separation
- 8,464 km (approx.)
- Last such locator decoded
- 2026-06-08 00:09 UTC
Other locator fields attributed to this token: EL97 (5).
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 UTC | Band | AC4JU S/N | Counterpart | Counterpart S/N | Msgs | Capture |
|---|---|---|---|---|---|---|
| 09-20 02:13 | 40m | - / -15 | PD2ET | -10 / - | 2 | ✓ Closing fragment |
| 09-20 02:07 | 40m | - / -10 | SV2HTW | +4 / - | 3 | ✓ Closing fragment |
| 09-20 02:04 | 40m | - / -13 | PA3DTN | 0 / - | 3 | ✓ Closing fragment |
| 09-20 01:55 | 40m | - / -8 | PD2ET | -6 / - | 2 | ✓ Closing fragment |
| 09-20 01:09 | 40m | - / -16 | F5NBU | +8 / - | 5 | Partial capture |
| 08-25 20:42 | 20m | - / - | W3HF | -17 / - | 3 | Partial capture |
| 08-25 20:19 | 20m | - / -15 | EA2DDG | -10 / - | 4 | ✓ Closing fragment |
| 08-25 20:10 | 20m | - / - | PD1ADA | +13 / - | 6 | Partial capture |
| 07-02 22:25 | 20m | - / - | IW9HPG | -4 / - | 2 | Partial capture |
Recent FT8 messages decoded at SO8OO
Frequency values are decoder audio offsets in hertz, not RF frequencies.
UTC dB Audio Message 011115 +7 1414 AC4JU F5NBU R-16 (x2) 014215 +1 1415 AC4JU PD9OH JO21 014245 -11 565 AC4JU SN5J KO02 014645 -10 1531 AC4JU OS4K -08 015500 -7 2088 AC4JU PD2ET -08 (x2) 020415 -2 752 AC4JU PA3DTN -13 (x3) 020715 +5 801 AC4JU SV2HTW -10 (x3) 021315 -8 939 AC4JU PD2ET RR73 (x2)
UTC dB Audio Message 201015 +14 2036 AC4JU PD1ADA JO21 (x6) 201915 -7 1630 AC4JU EA2DDG IN82 (x4) 202915 -19 1247 AC4JU WA4FU RR73 204245 -11 1219 AC4JU W3HF EL97 (x3) 210845 -1 479 AC4JU N3GTY FN10
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