JA4WLF — FT8 activity observed at SO8OO

DXCC entity inferred from callsign: Japan Most frequent locator attributed to this token: PM64

Receiver-side FT8 activity involving JA4WLF, decoded by SO8OO in southeastern Poland. 104 FT8 messages attributed to this token as transmitter, on 20m, across 6 UTC dates in the available aggregate history. Observed between 2026-06-06 and 2026-06-17.

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 104 FT8 messages attributed to JA4WLF as the transmitting token by decoded message structure across 6 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 (100%), so no unique busiest interval is claimed. Received S/N was mixed across SO8OO's weak, moderate and strong ranges; the estimated median was -9 dB.

Overview

104
Messages attributed
6
UTC dates decoded
15
Active 15-min windows
-9 dB
Estimated median S/N

Bands

First attributed message: 2026-06-06
Last attributed message: 2026-06-17 19:56 UTC

Observed FT8 message patterns

Attributed sample
104 messages
Active dates
6 UTC dates
Estimated median S/N
-9 dB
Estimated 10th-90th percentile
-15 to -6 dB
Recurring-pattern threshold
Met

SO8OO display ranges among successful decodes: weak (≤ -16 dB) 6, moderate (-15 to -9 dB) 59, strong (≥ -8 dB) 39.

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 JA4WLF in decoded directed-looking exchanges:

Most frequent locator attributed to JA4WLF

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
PM64 · 42 decoded messages
SO8OO receiver locator
KN09VW
Locator-centre separation
8,453 km (approx.)
Last such locator decoded
2026-06-17 19:56 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 UTCBandJA4WLF S/NCounterpartCounterpart S/NMsgsCapture
08-31 11:41 20m - / -7 UA3ZQN +5 / - 3 ✓ Closing fragment
08-24 20:57 20m - / -15 DH2RL -9 / - 2 ✓ Closing fragment
07-16 21:03 20m - / - F5PBG -8 / - 4 Partial capture
07-16 21:01 20m - / -15 F5NNN -8 / - 5 ✓ Closing fragment
07-16 20:33 20m - / +4 IS0AEL +2 / - 2 ✓ Closing fragment
07-16 20:17 20m - / -20 EA4BU -17 / - 5 Partial capture
06-23 20:44 20m - / - M0DHO +6 / - 2 ✓ Closing fragment

Recent FT8 messages decoded at SO8OO

Frequency values are decoder audio offsets in hertz, not RF frequencies.

20m
UTC    dB Audio  Message
210130  -7 1140  JA4WLF F5NNN IN94 (x3)
210300 -10 1191  JA4WLF F5PBG IN78
210300  -5 1140  JA4WLF F5NNN 73
210330  -8 1191  JA4WLF F5PBG IN78 (x3)
211345  -7 1251  JA4WLF EB5DFU -19
205715 -13 2287  JA4WLF DH2RL R-15 (x2)
195300 -12 1124  JA4WLF TA2ED RR73
114115  +8 2462  JA4WLF UA3ZQN KO90 (x3)

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