JH4RUF — FT8 activity observed at SO8OO

DXCC entity inferred from callsign: Japan Most frequent locator attributed to this token: PM74

Receiver-side FT8 activity involving JH4RUF, decoded by SO8OO in southeastern Poland. 1 FT8 messages attributed to this token as transmitter, on 40m, across 1 UTC dates in the available aggregate history. Last observed 2026-09-06.

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 1 FT8 messages attributed to JH4RUF as the transmitting token by decoded message structure across 1 UTC dates in the available aggregate history. The available sample contains attributed decodes on 40 m (100%). The sample is too small to infer a recurring UTC-hour or received-S/N pattern.

Overview

Messages attributed

UTC dates decoded

Active 15-min windows

S/N pattern not inferred

Bands

40m · 1

First attributed message: 2026-09-06
Last attributed message: 2026-09-06 20:43 UTC

Observed FT8 message patterns

Attributed sample: 1 messages
Active dates: 1 UTC dates
S/N summary: Too few decodes
S/N percentile sample: Too small
Recurring-pattern threshold: Not met

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 JH4RUF in decoded directed-looking exchanges:

S57MPU · Slovenia DL8TV · Fed. Rep. of Germany LZ2INP · Bulgaria OE3UKW · Austria ON6AA · Belgium RK4PR · European Russia SV2HTW · Greece EA7ST · Spain LY7M · Lithuania LZ1GC · Bulgaria R8CKD · Asiatic Russia SV5BYP · Dodecanese

Most frequent locator attributed to JH4RUF

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: PM74
SO8OO receiver locator: KN09VW
Locator-centre separation: 8,565 km (approx.)
Last such locator decoded: 2026-09-06 20:43 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	JH4RUF S/N	Counterpart	Counterpart S/N	Msgs	Capture
09-06 20:37	40m	- / -22	DK7ZT	-5 / -	4	Partial capture
09-06 20:32	40m	- / -7	LZ1GC	+17 / -	9	✓ Closing fragment
09-06 20:31	40m	- / -10	R8CKD	-7 / -	3	✓ Closing fragment
09-06 20:30	40m	- / -13	SV5BYP	-2 / -	2	✓ Closing fragment
09-05 19:57	40m	- / -17	EA7ST	+14 / -	3	✓ Closing fragment
09-03 18:19	160m	- / -16	S57MPU	+16 / -	7	✓ Closing fragment
08-29 21:27	40m	- / -	DF7EF	+4 / -	2	Partial capture
08-21 15:13	20m	- / -9	PA2JCB	-2 / -	2	Partial capture
08-21 15:10	20m	- / -	DL1R	+11 / -	8	Partial capture
08-21 15:10	20m	- / -7	DL8TV	+10 / -	4	✓ Closing fragment
08-21 15:08	20m	- / -	SP6AXW	-15 / -	4	Partial capture
08-21 15:06	20m	- / -	DB9LG	+2 / -	2	Partial capture
08-21 15:03	20m	- / -5	RK4PR	-8 / -	2	✓ Closing fragment
08-21 14:59	20m	- / 0	LZ2INP	-11 / -	14	✓ Closing fragment
08-21 14:56	20m	- / -	M0LAD	-3 / -	2	Partial capture
08-21 14:56	20m	- / -9	ON6AA	+20 / -	2	✓ Closing fragment
08-21 14:52	20m	- / -	ON6AA	+10 / -	2	Partial capture
07-26 19:20	40m	- / -	S57BTI	+8 / -	2	Partial capture
07-26 19:19	40m	- / -19	YO4GIY	-15 / -	2	✓ Closing fragment
07-18 14:51	20m	- / -20	MI0JZZ	-4 / -	2	Partial capture
07-18 14:49	20m	- / -14	SV2HTW	-5 / -	2	✓ Closing fragment
07-10 19:47	20m	- / -	R6DBT	-11 / -	4	Partial capture
07-10 19:37	20m	- / -20	OE3UKW	+7 / -	3	✓ Closing fragment
07-10 19:32	20m	- / -	LZ2VQ	-4 / -	2	Partial capture
07-10 19:11	40m	- / -	RX7KIR	-12 / -	2	Partial capture
07-09 17:00	40m	- / +6	RJ6B	-6 / -	4	Partial capture
07-09 16:58	40m	- / -15	LY7M	-10 / -	2	✓ Closing fragment

Recent FT8 messages decoded at SO8OO

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

40m

UTC    dB Audio  Message
203245  -6  488  JH4RUF R8CKD 73
203245 +15  642  JH4RUF LZ1GC KN22 (x6)
203645  -6 2096  JH4RUF IU4DTV -12
203715  -8 1906  JH4RUF DK7ZT -22
203745 +15  642  JH4RUF LZ1GC 73
203745  -3 1906  JH4RUF DK7ZT -22
203815 +17  642  JH4RUF LZ1GC 73
203815  -3 1906  JH4RUF DK7ZT -22 (x2)
204315 -24 1869  CN8NS JH4RUF PM74

160m

UTC    dB Audio  Message
181945 +16 2402  JH4RUF S57MPU -16 (x7)

20m

UTC    dB Audio  Message
151030  +8 2655  JH4RUF DL1R JN58
151100  +1  363  JH4RUF DL9IQ JO40
151100 +11 2374  JH4RUF DL8TV JN49
151100 +15 2656  JH4RUF DL1R JN58
151200 +15 2374  JH4RUF DL8TV R-07
151200  +9 2655  JH4RUF DL1R JN58
151230  +6 2374  JH4RUF DL8TV 73
151230  +6 2655  JH4RUF DL1R JN58 (x2)
151330  -3  699  JH4RUF PA2JCB JO21
151330 +11 2655  JH4RUF DL1R JN58
151400  -2  699  JH4RUF PA2JCB R-09
151400 +13 2655  JH4RUF DL1R JN58 (x2)
151600  -4  927  JH4RUF PA3DTR JO21

FT8DB and SO8OO WebSDR are a hobby project maintained solo. ☕ Buy me a coffee