JS1NDM — FT8 activity observed at SO8OO

DXCC entity inferred from callsign: Japan Most frequent locator attributed to this token: PM95

Receiver-side FT8 activity involving JS1NDM, decoded by SO8OO in southeastern Poland. 10 FT8 messages attributed to this token as transmitter, on 40m, across 4 UTC dates in the available aggregate history. Observed between 2026-08-22 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 10 FT8 messages attributed to JS1NDM as the transmitting token by decoded message structure across 4 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

10
Messages attributed
4
UTC dates decoded
6
Active 15-min windows
-16 dB
Estimated median S/N

Bands

40m · 10
First attributed message: 2026-08-22
Last attributed message: 2026-09-19 20:47 UTC

Observed FT8 message patterns

Attributed sample
10 messages
Active dates
4 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) 4, strong (≥ -8 dB) 1.

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 JS1NDM in decoded directed-looking exchanges:

Most frequent locator attributed to JS1NDM

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
PM95 · 5 decoded messages
SO8OO receiver locator
KN09VW
Locator-centre separation
8,693 km (approx.)
Last such locator decoded
2026-09-19 20:47 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 UTCBandJS1NDM S/NCounterpartCounterpart S/NMsgsCapture
09-19 20:44 40m -10 / - CN8NS - / - 4 Partial capture
09-13 20:29 40m - / - PD0LBY -8 / - 3 Partial capture
09-13 20:24 40m -19 / -15 OT7K +9 / - 6 ✓ Closing observed
09-13 20:14 40m - / - DK8HC -8 / - 4 Partial capture
09-13 20:11 40m - / -19 II6IALU 0 / - 2 Partial capture
09-01 20:38 40m - / - F8MRQ -9 / - 3 Partial capture
09-01 20:33 40m - / -2 IZ6SCG -4 / - 5 ✓ Closing fragment
09-01 20:32 40m - / -12 TA2EE -8 / - 5 ✓ Closing fragment
09-01 20:32 40m - / -13 EU3LA -16 / - 2 ✓ Closing fragment
09-01 20:32 40m - / - IK2AUK -13 / - 2 Partial capture
09-01 20:32 40m - / - IK6CNM +6 / - 2 Partial capture
09-01 20:28 40m - / -15 F8MRQ -1 / - 5 Partial capture
09-01 20:28 40m - / - YO9BGU -2 / - 2 Partial capture
09-01 20:27 40m -17 / - D2ACE - / +5 2 ✓ Closing fragment
08-22 20:20 40m -13 / -7 UT6HN +11 / -11 4 ✓ Full exchange observed
08-22 20:19 40m -22 / -16 ON4AOI +14 / -25 2 Partial capture
08-06 20:23 40m - / - DB9LG 0 / - 3 Partial capture
08-06 20:19 40m - / - R7OP -12 / - 2 Partial capture
07-23 20:15 40m - / - F4JTM -2 / - 2 Partial capture
07-23 20:14 40m - / - DL5EBS -11 / - 6 Partial capture
07-18 20:28 20m - / -15 HB0/HB9FXF -8 / - 2 Partial capture
07-18 20:24 20m - / -17 F4MUD -6 / - 5 Partial capture
07-09 20:44 20m - / -16 <...> -22 / - 2 Partial capture
07-09 20:42 20m - / - ON6AA -18 / - 2 ✓ Closing fragment
06-27 20:47 20m - / -10 US5HL -14 / - 2 Partial capture
06-27 20:29 20m - / -10 UR1CCO -18 / - 2 Partial capture
06-25 20:34 20m - / -10 IQ0VT -14 / - 3 ✓ Closing fragment

Recent FT8 messages decoded at SO8OO

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

40m 
UTC    dB Audio  Message
201600 -13  598  JS1NDM DK8HC JO42
202445 -19 2132  OT7K JS1NDM PM95
202500  +8 1560  JS1NDM OT7K -15 (x5)
202915  -8 1534  JS1NDM PD0LBY JO22 (x3)
203515  -4  428  JS1NDM SV8/F6BLP -03
204445  -4 2912  CN8NS JS1NDM PM95 (x4)
20m 
UTC    dB Audio  Message
204715 -17 2382  JS1NDM US5HL -10 (x2)
204230 -21 1479  JS1NDM ON6AA JO11 (x2)
204400 -20 1947  JS1NDM <...> -16 (x2)
202430  -3 1902  JS1NDM F4MUD -17 (x5)
202830 -10 2583  JS1NDM HB0/HB9FXF -15 (x2)
204430  -4 1437  JS1NDM E77FN JN93
204945  -3 1145  JS1NDM OZ1HBM -11

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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