JA7YAA — FT8 activity observed at SO8OO

DXCC entity inferred from callsign: Japan Most frequent locator attributed to this token: QM08

Receiver-side FT8 activity involving JA7YAA, decoded by SO8OO in southeastern Poland. 7 FT8 messages attributed to this token as transmitter, on 40m, across 1 UTC dates in the available aggregate history. Last observed 2026-09-18.

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 7 FT8 messages attributed to JA7YAA as the transmitting token by decoded message structure across 1 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 -16 dB; no usual signal pattern is inferred.

Overview

7
Messages attributed
1
UTC dates decoded
2
Active 15-min windows
-16 dB
Estimated median S/N

Bands

First attributed message: 2026-09-18
Last attributed message: 2026-09-18 20:13 UTC

Observed FT8 message patterns

Attributed sample
7 messages
Active dates
1 UTC dates
Estimated median S/N
-16 dB
S/N percentile sample
Too small
Recurring-pattern threshold
Not met

SO8OO display ranges among successful decodes: weak (≤ -16 dB) 5, moderate (-15 to -9 dB) 2, 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 JA7YAA in decoded directed-looking exchanges:

Most frequent locator attributed to JA7YAA

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
QM08 · 2 decoded messages
SO8OO receiver locator
KN09VW
Locator-centre separation
8,525 km (approx.)
Last such locator decoded
2026-09-18 20:02 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 UTCBandJA7YAA S/NCounterpartCounterpart S/NMsgsCapture
09-18 20:14 40m - / -10 IZ5IMD +3 / - 3 ✓ Closing fragment
09-18 20:13 40m -20 / - 9A5E -19 / -9 3 ✓ Closing observed
09-18 20:05 40m -16 / -9 R7ZY +2 / -16 6 ✓ Full exchange observed
09-18 20:01 40m -16 / - EA5KB - / - 2 Partial capture
09-18 20:01 40m - / - DL1SVI -4 / - 3 Partial capture
09-18 19:59 40m - / - RV3V +5 / - 2 Partial capture
09-18 19:56 40m -16 / -12 SM2OTU -7 / - 3 ✓ Closing observed
09-18 19:48 80m - / -13 OH4MDY -2 / - 2 ✓ Closing fragment
09-13 20:39 40m - / -16 YO4NF -22 / - 2 ✓ Closing fragment
09-13 20:36 40m - / - PD0IFI +4 / - 2 Partial capture
09-13 20:32 40m - / - DK1GP 0 / - 9 Partial capture
09-13 20:31 40m - / -15 OZ7CL +8 / - 2 ✓ Closing fragment
09-08 16:50 80m - / -18 UX5UO +18 / - 3 ✓ Closing fragment
08-31 20:22 40m - / - DL3MIB +16 / - 7 Partial capture

Recent FT8 messages decoded at SO8OO

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

40m
UTC    dB Audio  Message
200200  -6 1914  JA7YAA DL1SVI JO60
200215 -16 1782  EA5KB JA7YAA QM08
200500  +0 2612  JA7YAA R7ZY KN98 (x2)
200545 -18 1781  R7ZY JA7YAA -16
200600  +2 2612  JA7YAA R7ZY R-09
200615 -15 1781  R7ZY JA7YAA RR73
200630  +4 2612  JA7YAA R7ZY 73
200830 +16  445  JA7YAA PD0IFI JO32
201315 -20 1780  9A5E JA7YAA R-09
201330 -19 2170  JA7YAA 9A5E RR73
201345 -20 1780  9A5E JA7YAA 73
201430  +3 2212  JA7YAA IZ5IMD JN53 (x3)
80m
UTC    dB Audio  Message
165030 +17 1192  JA7YAA UX5UO KO50 (x3)
194600  -1 1034  JA7YAA OH4MDY RR73 (x3)

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