GM4SJB — FT8 activity observed at SO8OO
Receiver-side FT8 activity involving GM4SJB, decoded by SO8OO in southeastern Poland. 144 FT8 messages attributed to this token as transmitter, on 20m, across 5 UTC dates in the available aggregate history. Observed between 2026-06-10 and 2026-08-27.
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 144 FT8 messages attributed to GM4SJB as the transmitting token by decoded message structure across 5 UTC dates in the available aggregate history. The largest monitored-band total was 20 m (100%). Several six-hour UTC windows tied for the largest share (80%), so no unique busiest interval is claimed. Received S/N was mixed across SO8OO's weak, moderate and strong ranges; the estimated median was -14 dB.
Overview
Observed FT8 message patterns
- Attributed sample
- 144 messages
- Active dates
- 5 UTC dates
- Estimated median S/N
- -14 dB
- Estimated 10th-90th percentile
- -20 to -2 dB
- Recurring-pattern threshold
- Met
SO8OO display ranges among successful decodes: weak (≤ -16 dB) 58, moderate (-15 to -9 dB) 48, strong (≥ -8 dB) 38.
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.
Frequent counterpart tokens observed at SO8OO
Tokens most often paired with GM4SJB 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 GM4SJB
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
- IO88 · 56 decoded messages
- SO8OO receiver locator
- KN09VW
- Locator-centre separation
- 1,856 km (approx.)
- Last such locator decoded
- 2026-08-27 10:41 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 | GM4SJB S/N | Counterpart | Counterpart S/N | Msgs | Capture |
|---|---|---|---|---|---|---|
| 08-27 10:48 | 20m | - / -12 | EA5DKA | 0 / - | 2 | Partial capture |
| 08-27 10:45 | 20m | - / -2 | 9A6NTK | +13 / - | 3 | Partial capture |
| 08-27 10:37 | 20m | -16 / +2 | EA7GB | -16 / +4 | 9 | ✓ Full exchange observed |
| 08-27 10:37 | 20m | -24 / -4 | ON6VST | -18 / -9 | 3 | Partial capture |
| 08-27 10:29 | 20m | - / -3 | DL9MY | -2 / - | 2 | ✓ Closing fragment |
| 08-27 10:18 | 20m | -18 / - | EA7FU | - / -5 | 2 | ✓ Closing fragment |
| 08-27 10:10 | 20m | - / - | G4ZAM | -18 / - | 2 | ✓ Closing fragment |
| 08-27 10:08 | 20m | -11 / - | F1PPH | -8 / +7 | 2 | ✓ Closing observed |
| 08-27 10:03 | 20m | -16 / +5 | DL2KAC | -19 / -6 | 4 | ✓ Full exchange observed |
| 08-27 10:02 | 20m | - / -11 | R4FDW | -12 / - | 4 | Partial capture |
| 08-27 09:56 | 20m | -18 / -15 | GJ0KYZ | -9 / - | 5 | ✓ Closing observed |
| 08-27 09:55 | 20m | -7 / +3 | UT7UJ | +10 / - | 3 | ✓ Closing observed |
| 08-27 09:48 | 20m | - / - | F1PSX | -5 / - | 3 | ✓ Closing fragment |
| 08-07 22:27 | 20m | -7 / - | KF0FSJ | - / - | 2 | Partial capture |
| 08-07 22:26 | 20m | 0 / - | KF8WX | - / -20 | 2 | Partial capture |
| 08-07 22:23 | 20m | +1 / - | JA6BXA | - / -19 | 2 | ✓ Closing fragment |
| 08-07 22:21 | 20m | +2 / - | N2PPP | - / -16 | 2 | ✓ Closing fragment |
| 08-07 22:18 | 20m | - / - | CT1BFP | -20 / - | 3 | ✓ Closing fragment |
| 08-07 22:09 | 20m | -14 / - | 5N0YEN | - / - | 3 | Partial capture |
| 08-07 22:07 | 20m | -16 / - | RA0AN | - / -11 | 3 | Partial capture |
| 08-07 22:06 | 20m | -19 / - | BG5BNW | - / -24 | 3 | Partial capture |
| 08-07 22:05 | 20m | -18 / - | EA5JNN | -18 / - | 2 | ✓ Closing observed |
| 08-07 22:02 | 20m | -12 / - | JH7DFZ | - / -17 | 3 | Partial capture |
| 08-07 22:00 | 20m | -16 / - | JA1XIA | - / -16 | 3 | Partial capture |
| 08-07 21:59 | 20m | -22 / - | 5N0YEN | - / - | 2 | Partial capture |
| 08-07 21:56 | 20m | -19 / -4 | F1PBZ | 0 / -16 | 4 | ✓ Full exchange observed |
| 08-07 21:51 | 20m | -17 / - | JA5ROH/P | - / -18 | 7 | Partial capture |
| 08-07 21:49 | 20m | -18 / - | JA4DSC | - / -20 | 2 | ✓ Closing fragment |
| 08-07 21:48 | 20m | -10 / +4 | DD6CS | -22 / 0 | 3 | ✓ Full exchange observed |
| 08-07 21:45 | 20m | -12 / - | OH0ERF | - / - | 3 | Partial capture |
| 08-07 21:43 | 20m | -18 / - | BG3NQT | - / -14 | 2 | ✓ Closing fragment |
| 08-07 21:42 | 20m | -15 / +10 | G0OYR | -12 / - | 3 | ✓ Closing observed |
| 08-04 19:47 | 20m | - / 0 | F4AQD | -12 / - | 2 | Partial capture |
| 08-04 19:45 | 20m | -8 / - | UT8SQ | - / +6 | 2 | ✓ Closing fragment |
| 08-04 19:43 | 20m | -9 / - | IU1LEB | - / -2 | 2 | ✓ Closing fragment |
| 08-04 19:41 | 20m | -15 / - | OM2WW | - / -13 | 2 | ✓ Closing fragment |
| 08-04 19:37 | 20m | -9 / - | UT4QM | - / -17 | 5 | Partial capture |
| 08-04 19:32 | 20m | -8 / - | IZ7GIT | - / -9 | 6 | Partial capture |
| 08-04 19:30 | 20m | -12 / - | 9A6R | - / - | 2 | ✓ Closing fragment |
| 08-04 19:27 | 20m | -18 / -13 | F4MGP | -8 / - | 4 | ✓ Closing observed |
| 08-04 19:19 | 20m | -20 / - | <...> | - / -14 | 2 | Partial capture |
| 08-04 19:12 | 20m | -24 / -19 | TA7MMI | -18 / - | 3 | Partial capture |
| 07-05 20:02 | 20m | -17 / - | DF4TC | - / -15 | 2 | Partial capture |
| 07-05 19:51 | 20m | -14 / -21 | IZ0MQN | -12 / -4 | 3 | Partial capture |
Recent FT8 messages decoded at SO8OO
Frequency values are decoder audio offsets in hertz, not RF frequencies.
UTC dB Audio Message 103845 -19 2063 GM4SJB EA7GB IM77 103900 -15 1918 DL1SUZ GM4SJB -04 103915 -16 2063 GM4SJB EA7GB IM77 (x2) 104000 -18 1918 EA7GB GM4SJB +04 104015 -18 1918 GM4SJB EA7GB R+02 104030 -15 1918 EA7GB GM4SJB RR73 104130 -10 1918 CQ GM4SJB IO88 104400 -13 1918 DF6NL GM4SJB RR73 104545 +11 2423 GM4SJB 9A6NTK JN85 104615 -8 1116 GM4SJB DF6NL 73 104615 +14 2424 GM4SJB 9A6NTK JN85 (x2) 104845 +0 2063 GM4SJB EA5DKA IM99 (x2)
UTC dB Audio Message 173800 -5 1550 GM4SJB DL7BRD 73
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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