AI5B — FT8 activity observed at SO8OO

DXCC entity inferred from callsign: United States Most frequent locator attributed to this token: EM50

Receiver-side FT8 activity involving AI5B, decoded by SO8OO in southeastern Poland. 16 FT8 messages attributed to this token as transmitter, on 40m, 20m, across 4 UTC dates in the available aggregate history. Observed between 2026-07-27 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 16 FT8 messages attributed to AI5B as the transmitting token by decoded message structure across 4 UTC dates in the available aggregate history. The largest monitored-band total was 20 m (69%), followed by 40 m (31%). In this small sample, the estimated median decoder S/N was -10 dB; no usual signal pattern is inferred.

Overview

16
Messages attributed
4
UTC dates decoded
5
Active 15-min windows
-10 dB
Estimated median S/N

Bands

First attributed message: 2026-07-27
Last attributed message: 2026-09-19 00:00 UTC

Observed FT8 message patterns

Attributed sample
16 messages
Active dates
4 UTC dates
Estimated median S/N
-10 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) 10, strong (≥ -8 dB) 6.

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 AI5B in decoded directed-looking exchanges:

Most frequent locator attributed to AI5B

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
EM50 · 14 decoded messages
SO8OO receiver locator
KN09VW
Locator-centre separation
8,779 km (approx.)
Last such locator decoded
2026-09-19 00:00 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 UTCBandAI5B S/NCounterpartCounterpart S/NMsgsCapture
09-16 23:39 40m - / - MI7XHT -8 / - 2 Partial capture
09-16 23:37 40m -12 / -10 HZ1TT -7 / -13 6 ✓ Full exchange observed
08-10 02:25 80m - / - 9A4ZM +17 / - 3 Partial capture
07-27 00:27 20m -8 / - EP5TJS - / - 8 Partial capture
07-27 00:23 20m -1 / - EP5TJS - / - 3 Partial capture
07-08 04:03 20m - / - UR4QFP -5 / - 6 Partial capture

Recent FT8 messages decoded at SO8OO

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

40m
UTC    dB Audio  Message
235530 -13 2256  D2ACE AI5B EM50
233745 -10 2541  HZ1TT AI5B EM50
233800 -11 1729  AI5B HZ1TT -10 (x2)
233845 -13 2541  HZ1TT AI5B R-13
233900  -5 1729  AI5B HZ1TT RR73
233930  -7 2462  AI5B MI7XHT IO64
233930  -4 1729  AI5B HZ1TT 73
234015 -10 2541  KA0BWH AI5B RR73
234100  -8 2461  AI5B MI7XHT IO64
000000 -12 2588  FG5FU AI5B EM50
80m
UTC    dB Audio  Message
022515 +18 2340  AI5B 9A4ZM JN86 (x3)
10m
UTC    dB Audio  Message
181830 -17 2404  AI5B IU3TOQ JN55
20m
UTC    dB Audio  Message
040400  -2 2398  AI5B UR4QFP KN77 (x4)
002315  -2 3003  EP5TJS AI5B EM50 (x11)

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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