JH4SLF — reception at SO8OO

Signals decoded by SO8OO in southeastern Poland. FT8 and CW have separate histories; all times are UTC.

FT8 activity

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

Receiver-side FT8 activity involving JH4SLF, decoded by SO8OO in southeastern Poland. 7 FT8 messages attributed to this token as transmitter, on 20m, across 1 UTC dates in the available aggregate history. Last observed 2026-06-18.

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 JH4SLF as the transmitting token by decoded message structure across 1 UTC dates in the available aggregate history. The largest monitored-band total was 20 m (100%). In this small sample, the estimated median decoder S/N was -11 dB; no usual signal pattern is inferred.

Overview

Messages attributed

UTC dates decoded

Active 15-min windows

-11 dB

Estimated median S/N

Bands

20m · 7

First attributed message: 2026-06-18
Last attributed message: 2026-06-18 20:29 UTC

Observed FT8 message patterns

Attributed sample: 7 messages
Active dates: 1 UTC dates
Estimated median S/N: -11 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) 5, strong (≥ -8 dB) 2.

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 JH4SLF in decoded directed-looking exchanges:

ON4IQ · Belgium DL5XJ · Fed. Rep. of Germany F8FKI · France LB7ZG · Norway LX1JH · Luxembourg M5BFL · England OK2ZAW · Czech Republic PA3EWP · Netherlands R2DDA · European Russia R4FDD · European Russia R6FGF · European Russia YL2KF · Latvia

Most frequent locator attributed to JH4SLF

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 · 4 decoded messages
SO8OO receiver locator: KN09VW
Locator-centre separation: 8,453 km (approx.)
Last such locator decoded: 2026-06-18 20:14 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 UTC	Band	JH4SLF S/N	Counterpart	Counterpart S/N	Msgs	Capture
10-29 18:02	160m	- / -	UR5EDX	-18 / -	3	Partial capture
10-21 18:02	40m	- / -17	R6DJR	-4 / -	7	Partial capture
10-19 20:31	40m	- / -9	LX1JH	+18 / -	2	✓ Closing fragment
10-19 20:07	40m	- / -15	R4FDD	+7 / -	3	✓ Closing fragment
10-17 18:52	40m	- / -	R2ASY	-14 / -	5	Partial capture
10-17 18:52	40m	- / -14	R2DDA	-6 / -	7	✓ Closing fragment
10-17 18:31	40m	- / -	UW5ESX	-14 / -	7	Partial capture
10-15 19:15	40m	- / -25	DL5XJ	+6 / -	4	✓ Closing fragment
10-15 19:10	40m	- / -18	R2GDV	-15 / -	2	Partial capture
10-08 19:10	40m	- / -19	YL2KF	+4 / -	2	✓ Closing fragment
09-20 19:05	40m	- / -	HB9ELE	+7 / -	4	Partial capture
09-17 20:45	40m	- / -11	F8FKI	+19 / -	2	✓ Closing fragment
09-17 20:23	40m	- / -17	M5BFL	+20 / -	4	✓ Closing fragment
08-25 19:55	40m	- / -	UA4FKT	+8 / -	2	Partial capture
08-25 19:54	40m	- / -12	OK2ZAW	+18 / -	2	✓ Closing fragment
08-24 19:16	40m	- / -21	LB7ZG	+9 / -	3	✓ Closing fragment
08-24 18:59	40m	- / -16	PA3EWP	+12 / -	2	✓ Closing fragment
08-20 19:11	20m	- / -19	ON4IQ	+20 / -	4	✓ Closing fragment

Recent FT8 messages decoded at SO8OO

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

40m

UTC    dB Audio  Message
185600  -4 2403  JH4SLF R2DDA RR73
200745  +3 2855  JH4SLF R4FDD LO33 (x3)
203130 +20 2855  JH4SLF LX1JH -09 (x2)
180245  -8 2777  JH4SLF R6DJR -17 (x7)
205345  -5  358  JH4SLF R6FGF RR73
205045 -10 1708  JH4SLF Z34K -17

160m

UTC    dB Audio  Message
180215 -16 1306  JH4SLF UR5EDX KN78 (x3)

20m

UTC    dB Audio  Message
184700 -16  722  JH4SLF TT1GD -18
191115 +21 2702  JH4SLF ON4IQ JO20 (x4)

CW

No CW receptions recorded for this callsign in the last 30 days.

Explore CW reception at SO8OO

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