OP4F — FT8 activity observed at SO8OO
Receiver-side FT8 activity involving OP4F, decoded by SO8OO in southeastern Poland. 15 FT8 messages attributed to this token as transmitter, on 40m, 20m, across 4 UTC dates in the available aggregate history. Observed between 2026-06-10 and 2026-09-19.
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 15 FT8 messages attributed to OP4F as the transmitting token by decoded message structure across 4 UTC dates in the available aggregate history. The largest monitored-band total was 40 m (93%), followed by 20 m (7%). In this small sample, the estimated median decoder S/N was -21 dB; no usual signal pattern is inferred.
Overview
Bands
Last attributed message: 2026-09-19 09:17 UTC
Observed FT8 message patterns
- Attributed sample
- 15 messages
- Active dates
- 4 UTC dates
- Estimated median S/N
- -21 dB
- S/N percentile sample
- Too small
- Recurring-pattern threshold
- Not met
SO8OO display ranges among successful decodes: weak (≤ -16 dB) 15, moderate (-15 to -9 dB) 0, 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 OP4F in decoded directed-looking exchanges:
Most frequent locator attributed to OP4F
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 · 11 decoded messages
- SO8OO receiver locator
- KN09VW
- Locator-centre separation
- 1,192 km (approx.)
- Last such locator decoded
- 2026-09-19 09:17 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 | OP4F S/N | Counterpart | Counterpart S/N | Msgs | Capture |
|---|---|---|---|---|---|---|
| 09-18 09:56 | 40m | - / - | 9A4ZM | -14 / - | 2 | Partial capture |
| 09-18 09:56 | 40m | - / - | DK7UY | -12 / - | 2 | Partial capture |
| 09-18 09:40 | 40m | - / - | 9A4ZM | -8 / - | 2 | Partial capture |
| 09-17 13:39 | 40m | -20 / - | PE8HB | - / - | 5 | Partial capture |
| 09-17 13:32 | 40m | -22 / - | ON4DN | - / +3 | 2 | Partial capture |
| 09-17 13:26 | 40m | -22 / - | ON6CQ | - / - | 2 | Partial capture |
| 09-17 13:25 | 40m | -20 / - | ON8WR | - / 0 | 2 | ✓ Closing fragment |
| 09-11 09:05 | 40m | - / - | F5RRS | -5 / - | 3 | Partial capture |
| 09-11 09:02 | 40m | -23 / - | PA5VEN | -19 / - | 2 | ✓ Closing observed |
Recent FT8 messages decoded at SO8OO
Frequency values are decoder audio offsets in hertz, not RF frequencies.
UTC dB Audio Message 133215 -22 2104 ON4DN OP4F JO21 (x2) 133900 -18 2104 PE8HB OP4F JO21 (x6) 094030 -4 1645 OP4F 9A4ZM JN86 (x2) 095630 -13 393 OP4F DK7UY JO44 095630 -11 1665 OP4F 9A4ZM JN86 095700 -10 392 OP4F DK7UY JO44 095700 -16 1665 OP4F 9A4ZM JN86 091730 -24 1637 ON2BER OP4F JO21
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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