RJ7K — FT8 activity observed at SO8OO
Receiver-side FT8 activity involving RJ7K, decoded by SO8OO in southeastern Poland. 9 FT8 messages attributed to this token as transmitter, on 40m, across 2 UTC dates in the available aggregate history. Observed between 2026-09-14 and 2026-09-28.
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 9 FT8 messages attributed to RJ7K 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 -5 dB; no usual signal pattern is inferred.
Overview
Observed FT8 message patterns
- Attributed sample
- 9 messages
- Active dates
- 2 UTC dates
- Estimated median S/N
- -5 dB
- S/N percentile sample
- Too small
- Recurring-pattern threshold
- Not met
SO8OO display ranges among successful decodes: weak (≤ -16 dB) 0, moderate (-15 to -9 dB) 2, strong (≥ -8 dB) 7.
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 RJ7K in decoded directed-looking exchanges:
Most frequent locator attributed to RJ7K
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
- KN75 · 3 decoded messages
- SO8OO receiver locator
- KN09VW
- Locator-centre separation
- 1,102 km (approx.)
- Last such locator decoded
- 2026-09-28 18:03 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 UTC | Band | RJ7K S/N | Counterpart | Counterpart S/N | Msgs | Capture |
|---|---|---|---|---|---|---|
| 09-28 18:03 | 40m | - / +3 | SV9/OM1ARH | -10 / - | 2 | Partial capture |
| 09-28 18:03 | 40m | -10 / - | N7NU/VP9 | - / -13 | 3 | Partial capture |
| 09-14 16:56 | 40m | -6 / - | R9OOF | - / -10 | 2 | Partial capture |
| 09-14 16:54 | 40m | -5 / -8 | R3PLN | -12 / -4 | 5 | ✓ Full exchange observed |
Recent FT8 messages decoded at SO8OO
Frequency values are decoder audio offsets in hertz, not RF frequencies.
UTC dB Audio Message 165430 -6 2335 R3PLN RJ7K KN75 165445 -13 1184 RJ7K R3PLN -08 165500 -5 2335 R3PLN RJ7K R-04 165515 -10 1184 RJ7K R3PLN RR73 165530 -3 2334 R3PLN RJ7K 73 165600 -4 2334 R9OOF RJ7K R-10 (x2) 170200 -1 2368 RX9ABI RJ7K KN75 180315 -13 2370 N7NU/VP9 RJ7K KN75 180330 -9 2740 RJ7K SV9/OM1ARH +03 (x2) 180445 -12 2371 N7NU/VP9 RJ7K R-13 (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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