4X5JK — 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: Israel Most frequent locator attributed to this token: KM71

Receiver-side FT8 activity involving 4X5JK, decoded by SO8OO in southeastern Poland. 3,429 FT8 messages attributed to this token as transmitter, on 80m, 60m, 40m, 20m, 10m, across 53 UTC dates in the available aggregate history. Observed between 2026-06-07 and 2026-11-05.

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 3,429 FT8 messages attributed to 4X5JK as the transmitting token by decoded message structure across 53 UTC dates in the available aggregate history. The largest monitored-band total was 40 m (62%), followed by 60 m (23%) and 20 m (9%). Most decodes (86%) fell within the six-hour window 18:00-00:00 UTC. Received S/N was mixed across SO8OO's weak, moderate and strong ranges; the estimated median was -12 dB.

Overview

3,429

Messages attributed

UTC dates decoded

318

Active 15-min windows

-12 dB

Estimated median S/N

Bands

80m · 170 60m · 802 40m · 2,130 20m · 324 10m · 3

First attributed message: 2026-06-07
Last attributed message: 2026-11-05 19:37 UTC

Observed FT8 message patterns

Attributed sample: 3,429 messages
Active dates: 53 UTC dates
Estimated median S/N: -12 dB
Estimated 10th-90th percentile: -19 to -4 dB
Recurring-pattern threshold: Met

SO8OO display ranges among successful decodes: weak (≤ -16 dB) 904, moderate (-15 to -9 dB) 1,601, strong (≥ -8 dB) 924.

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 4X5JK in decoded directed-looking exchanges:

IK4LZH · Italy ×3 R3DQK · European Russia ×3 SP6EFY · Poland ×3 UA9SY · Asiatic Russia ×3 DG9FEH · Fed. Rep. of Germany ×2 DJ9BI · Fed. Rep. of Germany ×2 DK7QJ · Fed. Rep. of Germany ×2 EA3JIJ · Spain ×2 HA7CH · Hungary ×2 RA6FYL · European Russia ×2 RQ2Q · European Russia ×2 TA2ED · Asiatic Turkey ×2

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 4X5JK

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: KM71 · 2,237 decoded messages
SO8OO receiver locator: KN09VW
Locator-centre separation: 2,325 km (approx.)
Last such locator decoded: 2026-11-05 19:37 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	4X5JK S/N	Counterpart	Counterpart S/N	Msgs	Capture
11-05 20:06	40m	- / -13	IN3ZWF	-13 / -	4	✓ Closing fragment
11-05 19:37	80m	- / -11	F5AUB	-10 / -	2	Partial capture
11-05 19:32	80m	-18 / -12	US8KA	+11 / +6	6	✓ Full exchange observed
11-05 19:30	80m	-16 / -9	OM2WW	+1 / -13	4	✓ Full exchange observed
11-05 19:28	80m	- / -	EA5OK	-20 / -	3	Partial capture
11-05 19:28	80m	-16 / -19	HA1TAB	+3 / -1	7	✓ Full exchange observed
11-05 19:27	80m	- / -3	UR7EU	-4 / -	3	✓ Closing fragment
11-05 19:25	80m	- / -15	F4EZJ	+10 / -	2	✓ Closing fragment
11-05 19:05	80m	- / -	OM2IB	+14 / -	5	Partial capture
11-04 19:43	80m	- / -9	LZ2KV	+2 / -	3	✓ Closing fragment
11-04 19:09	40m	- / -	PD7FS	-14 / -	5	Partial capture
11-04 19:06	40m	- / -	F3CJ	-12 / -	2	Partial capture
11-02 21:44	40m	-11 / -2	UX2QX	-8 / +3	8	Partial capture
11-02 21:40	40m	-12 / +1	UX2QX	-2 / -	4	✓ Closing observed
10-28 22:50	40m	-13 / -	EP2AES	- / +3	3	Partial capture
10-28 22:32	40m	-9 / -	DF7YT	- / -8	2	✓ Closing fragment
10-28 22:23	60m	-12 / -9	OE7FTI	-20 / -12	4	✓ Full exchange observed
10-28 22:21	60m	-14 / -	EA5FQ	- / -15	3	✓ Closing fragment
10-28 22:20	60m	- / -	DL1MST	-4 / -	6	Partial capture
10-28 22:13	60m	- / -	G7RTI	-8 / -	5	Partial capture
10-28 22:13	60m	-18 / -	YE7LOW	- / -9	2	✓ Closing fragment
10-28 22:11	60m	-20 / -4	EA2TW	-18 / 0	3	✓ Full exchange observed
10-28 22:09	60m	-20 / -	EA5KBG	- / +2	2	✓ Closing fragment
10-28 22:09	60m	- / -	DL1MST	-1 / -	6	Partial capture
10-28 22:05	60m	-20 / -11	OT4R	-15 / -15	5	✓ Full exchange observed
10-28 22:01	60m	- / +1	DL3HXS	-17 / -	6	Partial capture
10-28 22:01	60m	- / -11	YO9IE	-18 / -	3	✓ Closing fragment
10-28 21:59	60m	-21 / -	IU5TSN	- / -12	3	✓ Closing fragment
10-28 21:58	60m	- / -	DJ4IP	-10 / -	3	Partial capture
10-28 21:58	60m	- / -	G0SKW	-7 / -	2	Partial capture
10-28 21:56	60m	-22 / -	F4MXE	- / -11	2	✓ Closing fragment
10-28 21:50	60m	- / -14	F4LQD	-9 / -	3	✓ Closing fragment
10-28 21:48	60m	- / -	HB9HRR	-11 / -	3	Partial capture
10-28 21:46	60m	- / +7	IW8ELR	-17 / -	3	Partial capture
10-28 21:44	60m	- / -	DL1MST	-2 / -	2	Partial capture
10-28 21:40	60m	-16 / -6	ES2MA	-1 / -5	5	✓ Full exchange observed
10-28 21:36	60m	-16 / -	EB1EB	- / -14	2	✓ Closing fragment
10-28 21:35	60m	-12 / +3	DL1YFS	-4 / -11	13	✓ Full exchange observed
10-28 21:32	60m	-18 / -7	EA4DM	-20 / +1	3	✓ Full exchange observed
10-28 21:31	60m	- / -	HB9HRR	-11 / -	2	Partial capture
10-28 21:28	60m	- / -	DL1MST	-3 / -	4	Partial capture
10-28 21:23	60m	- / -	HB9HRR	-9 / -	4	Partial capture
10-28 21:20	60m	-16 / -8	SN2A	-18 / -	3	✓ Closing observed
10-28 21:20	60m	- / -	DK2YCT	-5 / -	3	Partial capture
10-28 21:19	60m	- / -	F5CFN	-17 / -	2	Partial capture
10-28 21:13	60m	-17 / +4	F8BON	-2 / +2	5	✓ Full exchange observed
10-28 21:11	60m	-19 / -5	F1IQH	-22 / -14	4	✓ Full exchange observed
10-28 21:08	60m	-17 / +1	F1JIO	-1 / -7	6	✓ Full exchange observed
10-28 21:06	60m	-16 / -4	F1LZV	-16 / -16	3	Partial capture
10-28 21:04	60m	-21 / -	OE2EJN	-24 / -6	3	✓ Closing observed

Recent FT8 messages decoded at SO8OO

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

40m

UTC    dB Audio  Message
191215 -16 1556  SP5DRK 4X5JK -09
191330 -19 1556  4X5JK PD7FS JO21
191345 -14 1557  CQ 4X5JK KM71                         a1 (x8)
195600 -23 2118  4X5JK HB9IJF R-15
200600 -12 1045  4X5JK IN3ZWF JN56 (x4)

80m

UTC    dB Audio  Message
193100  -2 1322  4X5JK OM2WW R-09 (x2)
193215 -18 1521  CQ 4X5JK KM71
193230  +9  424  4X5JK US8KA KO30
193245 -21 1521  US8KA 4X5JK +06
193300 +13  424  4X5JK US8KA R-12
193315 -15 1521  US8KA 4X5JK RR73
193330 +13  424  4X5JK US8KA R-12 (x2)
193515 -22 1520  CQ 4X5JK KM71
193530  -6 1630  4X5JK DH9AT JN67
193615 -20 1521  CQ 4X5JK KM71 (x2)
193730 -10 1521  4X5JK F5AUB JN13 (x2)

60m

UTC    dB Audio  Message
222330 -15 1552  OE7FTI 4X5JK -12
222345 -19 1629  4X5JK OE7FTI R-09
222430 -10 1552  OE7FTI 4X5JK RR73
222500 -11 1552  CQ 4X5JK KM71 (x12)

160m

UTC    dB Audio  Message
191430  -1 2101  4X5JK SP2LLP JO94 (x10)
235600  -2 3002  4X5JK LA1ZN JO59 (x5)

10m

UTC    dB Audio  Message
122945 -12  868  4X5JK EA7J IM77 (x2)
123145  -9 2037  4X5JK CT1ENI IM58 (x11)
124245 -23 1309  4X5JK DN9SIB R-16 (x2)

20m

UTC    dB Audio  Message
220545  -1 2469  4X5JK KB1EFS RR73
220630 -14 2469  CQ 4X5JK KM71
220745  +1 2469  4X5JK SQ1MNC JO73
220800 -15 2469  SQ1MNC 4X5JK +02
220945  -4 2469  4X5JK CT2HSM IN50
221030 -17 2470  CQ 4X5JK KM71
221045  -8 2469  4X5JK CT2HSM IN50
221100 -17 2469  CQ 4X5JK KM71                         a1
221130 -17 2469  CT2HSM 4X5JK -16
221145  -7 2469  4X5JK CT2HSM R-12 (x2)
221300 -18 2469  CT2HSM 4X5JK -16
221315  -4 2469  4X5JK CT2HSM R-11 (x3)

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.

CW

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

Explore CW reception at SO8OO

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