JI4JKO — FT8 activity observed at SO8OO

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

Receiver-side FT8 activity involving JI4JKO, decoded by SO8OO in southeastern Poland. 176 FT8 messages attributed to this token as transmitter, on 80m, 40m, 20m, across 34 UTC dates in the available aggregate history. Observed between 2026-06-10 and 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 176 FT8 messages attributed to JI4JKO as the transmitting token by decoded message structure across 34 UTC dates in the available aggregate history. The largest monitored-band total was 40 m (41%), followed by 20 m (38%) and 80 m (22%). Several six-hour UTC windows tied for the largest share (99%), so no unique busiest interval is claimed. Received S/N was mixed across SO8OO's weak, moderate and strong ranges; the estimated median was -12 dB.

Overview

176
Messages attributed
34
UTC dates decoded
56
Active 15-min windows
-12 dB
Estimated median S/N

Bands

80m · 38 40m · 72 20m · 66
First attributed message: 2026-06-10
Last attributed message: 2026-09-18 21:01 UTC

Observed FT8 message patterns

Attributed sample
176 messages
Active dates
34 UTC dates
Estimated median S/N
-12 dB
Estimated 10th-90th percentile
-19 to -1 dB
Recurring-pattern threshold
Met

SO8OO display ranges among successful decodes: weak (≤ -16 dB) 45, moderate (-15 to -9 dB) 76, strong (≥ -8 dB) 55.

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 JI4JKO 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 JI4JKO

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 · 71 decoded messages
SO8OO receiver locator
KN09VW
Locator-centre separation
8,453 km (approx.)
Last such locator decoded
2026-09-15 20:45 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 UTCBandJI4JKO S/NCounterpartCounterpart S/NMsgsCapture
09-19 21:13 80m - / -15 SV1DKR -10 / - 2 ✓ Closing fragment
09-18 21:02 40m - / - R4UAS -6 / - 2 Partial capture
09-18 21:00 40m -14 / -13 IT9PHU -12 / - 5 ✓ Closing observed
09-17 17:42 80m - / -4 S51DI +13 / - 4 ✓ Closing fragment
09-17 17:42 80m - / - ON6AA +1 / - 3 Partial capture
09-17 17:36 80m - / - ON6AA 0 / - 3 Partial capture
09-16 21:15 40m - / -15 PD0HLA +8 / - 2 Partial capture
09-16 21:14 40m - / -18 IW7EGY -16 / - 2 Partial capture
09-16 21:05 80m - / - SV1DKR +3 / - 2 Partial capture
09-16 21:02 80m - / -18 UA6JQ +7 / - 3 Partial capture
09-15 20:43 40m -14 / - S56LKP - / - 3 Partial capture
09-15 20:39 80m - / -18 OH2NAG -6 / - 2 ✓ Closing fragment
09-15 20:34 80m - / -14 LX2A +5 / - 2 ✓ Closing fragment
09-14 20:46 40m -5 / - EA8Y - / - 2 Partial capture
09-14 20:40 40m -14 / -9 IK1MNJ +9 / -4 5 ✓ Full exchange observed
09-14 20:05 80m - / - S51DI +13 / - 5 Partial capture
09-14 20:03 80m - / -15 UT5ZC +7 / - 3 ✓ Closing fragment
09-13 20:07 40m - / - RD7KW +8 / - 2 Partial capture
09-13 20:04 40m -12 / -12 IW0RLC +12 / - 3 ✓ Closing observed
09-13 19:59 40m - / -16 DJ0ABM +6 / - 3 ✓ Closing fragment
09-12 19:31 40m -13 / - CN8NS - / - 3 Partial capture
09-10 21:25 40m - / - IZ4EKI -4 / - 2 Partial capture
09-10 21:22 40m -8 / - LU8CJR - / - 4 ✓ Closing fragment
09-10 21:06 80m - / -19 YO6LM +6 / - 2 ✓ Closing fragment
09-10 16:10 40m - / - DK3WL -7 / - 3 Partial capture
09-10 16:09 40m - / -10 RD7LC -4 / - 2 Partial capture
09-10 16:09 40m - / -11 DL3TC +14 / - 8 ✓ Closing fragment
09-09 20:53 80m -20 / - G4BWP - / - 2 Partial capture
09-09 20:50 80m - / - TA1CM -15 / - 9 Partial capture
09-09 20:48 80m -20 / - YL3KZ - / - 2 Partial capture
09-09 20:41 80m -22 / -25 DJ0CL +11 / - 6 ✓ Closing observed
09-09 20:39 80m -19 / - SP8ONV -5 / - 2 ✓ Closing observed
09-09 20:37 80m - / - DK3ME -2 / - 4 Partial capture
09-09 20:35 80m - / -14 R6KX -6 / - 2 Partial capture
09-09 20:35 80m - / - DD7EE -10 / - 3 Partial capture
09-09 20:35 80m -16 / - DL9DX -2 / -19 4 ✓ Closing observed
09-09 20:33 80m -16 / - TA4RC - / -11 3 ✓ Closing fragment
09-09 20:31 80m - / -22 SP6JIU +23 / - 3 ✓ Closing fragment
09-09 20:30 80m - / - DA6IT -10 / - 2 Partial capture
09-09 20:30 80m - / - DA6LRW -8 / - 2 Partial capture
09-09 20:29 80m - / -15 R6KX -4 / - 8 Partial capture
09-09 20:28 80m -20 / -12 UR7FM -4 / -18 5 ✓ Full exchange observed
09-09 20:25 80m - / -7 SP2HNF +19 / - 2 ✓ Closing fragment
09-09 20:23 80m - / -13 RL6MT -11 / - 2 ✓ Closing fragment
09-09 20:22 80m - / - RC6OU +9 / - 2 Partial capture
09-09 20:21 80m - / - R6FX -24 / - 2 Partial capture
09-09 20:19 80m - / - ON6AA -4 / - 5 Partial capture
09-09 20:19 80m -16 / -11 IZ8WDH -7 / - 5 ✓ Closing observed
09-09 20:08 80m - / -19 RA3TD -20 / - 2 Partial capture
09-09 20:04 80m - / -9 PI4DX +6 / - 2 ✓ Closing fragment

Recent FT8 messages decoded at SO8OO

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

80m 
UTC    dB Audio  Message
210400 +11  598  JI4JKO UA6JQ R-18
210500  +5 1759  JI4JKO SV1DKR KM18 (x2)
173630  -2 2504  JI4JKO ON6AA JO11 (x4)
174230 +12 2180  JI4JKO S51DI -04 (x2)
174300  +5 2303  JI4JKO ON6AA JO11
174330 +13 2180  JI4JKO S51DI RR73
174330  -2 2303  JI4JKO ON6AA JO11
174400 +15 2180  JI4JKO S51DI RR73
211300 -11 2108  JI4JKO SV1DKR -15 (x2)
40m 
UTC    dB Audio  Message
204515 -11  485  S56LKP JI4JKO PM64
204600  -3 2761  JI4JKO DJ0MDC JN58
211445 -18 1071  JI4JKO IW7EGY JN80
211545  +6 2690  JI4JKO PD0HLA -15
211545  -7  460  JI4JKO 4L7T 73
211615 +11 2690  JI4JKO PD0HLA -15
211645 -14 1071  JI4JKO IW7EGY R-18
211715 -16  810  JI4JKO IU8RFW JN70
210000  -7  977  JI4JKO IT9PHU -13 (x4)
210145 -14  975  IT9PHU JI4JKO 73
210200  -5 2292  JI4JKO R4UAS KO85 (x2)
10m 
UTC    dB Audio  Message
091200  -9 2642  JI4JKO UR6QA KN77
091800 -16 2393  JI4JKO DN9OPA JN38
092430  +5 2172  JI4JKO DL9FCY +02 (x2)
082300 -13 1787  JI4JKO TA6B -03 (x2)
081315 -14 1575  JI4JKO SV9MBL RRR
080030 -22 1999  JI4JKO F1TXI RR73
052630 -19 2270  JI4JKO RQ7R KN64 (x4)
072945 -11  717  JI4JKO A92GE -16
070645 -22 1748  JI4JKO A41DV -07
093115 -11  496  JI4JKO <...> -06
20m 
UTC    dB Audio  Message
195400  -7 1628  JI4JKO G5TV R-11 (x2)
195930 -15 1068  JI4JKO IU5AWQ JN53 (x4)
200130  -4  609  JI4JKO F5SPJ -22 (x5)
225030  -9  872  JI4JKO CT2HEX -04 (x2)
230330  -6 1278  JI4JKO CT1FIU -17 (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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