JR4OZR — FT8 activity observed at SO8OO

DXCC entity inferred from callsign: Japan Most frequent locator attributed to this token: PM75

Receiver-side FT8 activity involving JR4OZR, decoded by SO8OO in southeastern Poland. 33 FT8 messages attributed to this token as transmitter, on 80m, 40m, across 8 UTC dates in the available aggregate history. Observed between 2026-07-11 and 2026-09-15.

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 33 FT8 messages attributed to JR4OZR as the transmitting token by decoded message structure across 8 UTC dates in the available aggregate history. The largest monitored-band total was 40 m (58%), followed by 80 m (42%). 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

33
Messages attributed
8
UTC dates decoded
13
Active 15-min windows
-9 dB
Estimated median S/N

Bands

First attributed message: 2026-07-11
Last attributed message: 2026-09-15 20:42 UTC

Observed FT8 message patterns

Attributed sample
33 messages
Active dates
8 UTC dates
Estimated median S/N
-9 dB
Estimated 10th-90th percentile
-16 to -5 dB
Recurring-pattern threshold
Met

SO8OO display ranges among successful decodes: weak (≤ -16 dB) 4, moderate (-15 to -9 dB) 13, strong (≥ -8 dB) 16.

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.

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 JR4OZR

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
PM75 · 6 decoded messages
SO8OO receiver locator
KN09VW
Locator-centre separation
8,477 km (approx.)
Last such locator decoded
2026-09-15 20:42 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 UTCBandJR4OZR S/NCounterpartCounterpart S/NMsgsCapture
09-18 20:56 80m - / -16 YL3KZ -4 / - 3 Partial capture
09-15 20:38 80m -9 / - LX2A - / -9 6 Partial capture
09-15 20:07 40m -8 / - RI1FJZ - / -11 2 Partial capture
09-13 20:38 80m - / - OK2VCR +5 / - 7 Partial capture
09-13 20:36 80m - / -15 UX1AA -5 / - 6 ✓ Closing fragment
09-13 20:35 80m - / -16 S59A +23 / - 2 ✓ Closing fragment
09-11 20:44 80m - / - DF8AA +10 / - 2 Partial capture
09-11 20:41 80m - / - DO2RG +2 / - 4 Partial capture
09-11 20:39 80m -12 / -12 RA6YDX -8 / - 5 ✓ Closing observed
09-11 20:38 80m - / - SV8TCK -6 / - 2 Partial capture
09-11 20:37 80m - / - RO2X +4 / - 3 Partial capture
09-11 20:36 80m - / -20 EA3FCQ -5 / - 5 ✓ Closing fragment
09-11 20:36 80m - / - DF8AA +7 / - 3 Partial capture
09-11 20:35 80m - / - G4ZFJ -1 / - 3 Partial capture
09-11 20:35 80m -11 / -16 Z62NS +4 / -16 4 ✓ Full exchange observed
09-11 20:35 80m - / -13 ON6AA +6 / - 4 ✓ Closing fragment
09-06 20:47 80m - / -9 5Z4VJ -22 / - 2 ✓ Closing fragment
09-02 16:43 80m - / - RM3ZR +2 / - 2 Partial capture
09-02 16:38 80m - / - RM3ZR +4 / - 3 Partial capture
09-02 16:38 80m - / - UA4FKT +2 / - 3 Partial capture
09-02 16:35 80m - / - RA3OR -8 / - 5 Partial capture
08-20 20:18 80m - / - EW8CW -7 / - 6 Partial capture
08-20 20:18 80m - / - HA7XL +19 / - 6 Partial capture
08-18 20:23 80m - / - DK5WL -13 / - 3 Partial capture
08-18 20:23 80m - / - SP2HNF +12 / - 6 Partial capture
08-17 20:41 40m -9 / - CN8NS - / -6 3 ✓ Closing fragment
08-09 20:22 40m -6 / +7 Z34K -8 / -8 4 ✓ Full exchange observed
08-09 20:22 40m - / - OK2VCR -9 / - 6 Partial capture
08-09 20:21 40m - / - RA6YDX -4 / - 6 Partial capture
08-09 20:19 40m -5 / +8 HA7FT -17 / -7 5 ✓ Full exchange observed
08-09 20:17 40m -5 / - LY1DY -12 / - 3 ✓ Closing observed
08-09 20:17 40m - / - RA6YDX -15 / - 5 Partial capture
08-09 20:16 40m -6 / - TF4M - / -15 2 ✓ Closing fragment
08-09 20:14 40m - / - ON5RZ -8 / - 3 Partial capture
08-09 20:10 40m -10 / - TF4M - / -16 2 Partial capture
08-09 20:01 40m - / - Z34K -19 / - 3 Partial capture
08-02 21:05 40m - / - SP2FWC -7 / - 4 Partial capture
08-02 21:04 40m - / - RN6HK -4 / - 3 Partial capture
08-02 20:44 40m - / - F5PBG -14 / - 2 Partial capture
08-02 20:42 40m - / - UR5EDX +1 / - 7 Partial capture
08-02 20:41 40m - / -14 LA0FA -13 / - 4 ✓ Closing fragment
08-02 20:38 40m - / - RC1C -20 / - 2 Partial capture
08-02 20:32 80m - / - SP8NR +12 / - 2 Partial capture
08-02 20:29 80m - / - SP8NR +4 / - 2 Partial capture
08-02 20:18 80m - / - E77EA -3 / - 3 Partial capture
08-02 20:18 80m - / - SP8NR +4 / - 2 Partial capture
08-02 20:17 80m -13 / -10 YO8PS +10 / - 3 ✓ Closing observed
08-02 20:10 80m - / - IK8WEC +3 / - 2 Partial capture
08-02 20:07 80m - / - SP2HNF +20 / - 3 Partial capture
08-02 20:07 80m - / - IK8WEC +3 / - 2 Partial capture

Recent FT8 messages decoded at SO8OO

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

80m
UTC    dB Audio  Message
203915  +2  984  JR4OZR OK2VCR JN89 (x6)
203800 -15 1048  LX2A JR4OZR -09 (x6)
205600  -6 1608  JR4OZR YL3KZ -16 (x3)
40m
UTC    dB Audio  Message
202345  -5  384  Z34K JR4OZR RR73
202400  -8  383  JR4OZR Z34K 73
202400  -2  484  JR4OZR RA6YDX LN04
202400 -10 1167  JR4OZR OK2VCR JN89
202430  -6  484  JR4OZR RA6YDX LN04
202430 -11 1167  JR4OZR OK2VCR JN89
202430 -12  385  JR4OZR G6CZC IO94
202500  -2 2796  JR4OZR ON5RZ JO21
204115  -7 2548  CN8NS JR4OZR -06 (x3)
204230 -21 1993  JR4OZR YO6KNZ KN26
204430  -2  599  JR4OZR SP4TKA KO14
200745  -9  750  RI1FJZ JR4OZR PM75 (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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