4Z5MU — FT8 activity observed at SO8OO
Receiver-side FT8 activity involving 4Z5MU, decoded by SO8OO in southeastern Poland. 12 FT8 messages attributed to this token as transmitter, on 40m, across 2 UTC dates in the available aggregate history. Observed between 2026-08-25 and 2026-08-26.
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 12 FT8 messages attributed to 4Z5MU as the transmitting token by decoded message structure across 2 UTC dates in the available aggregate history. The largest monitored-band total was 40 m (100%). In this small sample, the estimated median decoder S/N was -14 dB; no usual signal pattern is inferred.
Overview
Observed FT8 message patterns
- Attributed sample
- 12 messages
- Active dates
- 2 UTC dates
- Estimated median S/N
- -14 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) 8, 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).
Frequent counterpart tokens observed at SO8OO
Tokens most often paired with 4Z5MU 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 4Z5MU
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
- KM72 · 10 decoded messages
- SO8OO receiver locator
- KN09VW
- Locator-centre separation
- 2,224 km (approx.)
- Last such locator decoded
- 2026-08-26 18:13 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 UTC | Band | 4Z5MU S/N | Counterpart | Counterpart S/N | Msgs | Capture |
|---|---|---|---|---|---|---|
| 08-26 18:09 | 40m | -19 / - | II7MGMU | - / - | 2 | Partial capture |
| 08-26 17:56 | 40m | -20 / - | ES4RR | - / - | 2 | Partial capture |
| 08-25 23:59 | 40m | -14 / - | N8XY | - / - | 4 | Partial capture |
| 07-25 20:23 | 40m | - / -19 | GW5NIC | -7 / - | 2 | Partial capture |
| 07-22 22:07 | 40m | - / - | DL9KM | -14 / - | 6 | ✓ Closing fragment |
| 07-22 19:46 | 40m | - / -21 | OE9GWV | -6 / - | 3 | ✓ Closing fragment |
| 07-22 19:44 | 40m | - / -8 | OE1HLB | -10 / - | 2 | ✓ Closing fragment |
| 07-21 22:57 | 40m | - / - | UA4FKT | -10 / - | 3 | Partial capture |
| 07-17 19:10 | 40m | - / -13 | R3BDQ | -14 / - | 2 | Partial capture |
| 07-15 19:04 | 40m | - / - | OM5ALL | -10 / - | 2 | ✓ Closing fragment |
| 07-15 18:59 | 40m | - / -8 | EW2ZC | -8 / - | 4 | Partial capture |
| 07-15 18:55 | 40m | - / -6 | HG8IT | -18 / - | 3 | ✓ Closing fragment |
Recent FT8 messages decoded at SO8OO
Frequency values are decoder audio offsets in hertz, not RF frequencies.
UTC dB Audio Message 183830 -14 1818 ZL1GT 4Z5MU 73 192315 -16 1459 4Z5MU EN35UKR -14 235900 -13 1915 N8XY 4Z5MU KM72 (x4) 175430 -2 624 4Z5MU ES4TIX RR73 175500 -13 1587 4Z5MU IU3VQA JN65 175600 -18 1681 ES4RR 4Z5MU KM72 (x2) 180630 -13 1091 EU6UE 4Z5MU 73 180830 -14 1261 <HB0/HB9FXF> 4Z5MU KM72 180900 -17 1761 II7MGMU 4Z5MU KM72 (x2) 181315 -12 1760 YD5BAG 4Z5MU KM72
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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