K4ISU — FT8 activity observed at SO8OO

DXCC entity inferred from callsign: United States Locator transmitted in a decoded message: EM75

Receiver-side FT8 activity involving K4ISU, decoded by SO8OO in southeastern Poland. 160 related FT8 messages, 28 CQ messages, observed on 40m, 20m, across 11 UTC dates. Heard between 2026-05-08 and 2026-08-03.

These are automated observations at the SO8OO receiver, not the station's official logbook. Times are UTC. Decoder S/N describes messages received at SO8OO; inferred entity and location data may be inaccurate for portable, remote or special-event operation.

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

Overview

160

Related messages

CQ messages

UTC dates heard

-9 dB

Mean decoder S/N

Bands

20m 40m

First seen: 2026-05-08
Last seen: 2026-08-03 02:17 UTC

Frequent QSO partners observed at SO8OO

Stations K4ISU worked most often, as logged from our receiver:

IW3BYL · Italy YO6OGJ · Romania KF0OSW · United States KE8VPC · United States R5AV · European Russia EB5AL · Spain OH2ZZ · Finland IK2WSA · Italy RX6FN · European Russia EW4DX · Belarus EA4T · Spain KC3ZZ · United States

Activity Heatmap

Locator transmitted by K4ISU

Approximate centre of EM75, decoded 2026-07-29 04:11 UTC. A transmitted locator is not proof of the operator's permanent location.

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	K4ISU S/N	Counterpart	Counterpart S/N	Msgs	Capture
07-27 04:24	20m	- / -16	RN6MA	-12 / -	2	Partial capture
07-27 03:29	20m	- / -1	IZ2QPP	+3 / -	2	Partial capture
07-27 03:25	20m	- / -	RD3FY	-11 / -	4	Partial capture
07-27 02:52	20m	- / -	DL1R	-10 / -	3	Partial capture
06-29 03:28	40m	- / -	IK2ZJR	-9 / -	11	Partial capture
06-29 03:19	40m	- / -	IK2ZJR	-4 / -	5	Partial capture
06-29 03:15	40m	- / -	IK2ZJR	-6 / -	2	Partial capture
06-29 02:30	20m	- / -18	EB5AL	-5 / -	5	✓ Closing fragment
06-29 02:05	20m	- / -	EB5AL	-9 / -	5	Partial capture
06-22 04:01	20m	- / -12	UA6HBJ	+7 / -	3	✓ Closing fragment
06-22 03:47	20m	- / -	UA6HBJ	-4 / -	2	Partial capture
06-22 03:42	20m	- / -13	A71AT	-8 / -	4	✓ Closing fragment
06-22 02:32	20m	- / -5	W1ABY	-15 / -	2	Partial capture
06-21 05:42	20m	- / -	F5HNQ	-7 / -	3	Partial capture
06-21 05:37	20m	- / -13	EA1CQ	-16 / -	3	Partial capture
06-15 02:58	20m	- / -	TA2EE	-21 / -	2	Partial capture
06-15 02:48	20m	- / -24	HB9VAA	-7 / -	4	Partial capture
06-15 02:46	20m	-19 / -	KE7KPY	- / -10	3	Partial capture
06-15 02:43	20m	-18 / -	R4FDK	- / -9	5	✓ Closing fragment
06-15 02:36	20m	-17 / -	AA1ZZ	- / -13	2	Partial capture
06-15 02:24	20m	-18 / -	AG7KU	- / -15	2	Partial capture
06-15 02:22	20m	-20 / -	N8GMZ	- / -12	2	Partial capture
06-01 04:07	20m	-10 / -2	SP9UPH	-16 / -	2	Partial capture
06-01 03:58	20m	- / -	TA2EE	-7 / -	6	Partial capture
06-01 03:58	20m	-13 / -	YO6OGJ	- / -3	2	✓ Closing fragment
06-01 03:53	20m	-14 / -	RV3DBV	- / -21	2	Partial capture
06-01 03:47	20m	-22 / -	KC3ZZ	- / -23	2	✓ Closing fragment
06-01 03:37	20m	-12 / -	RA3QUA	- / -5	2	✓ Closing fragment
06-01 03:29	20m	-11 / -	RX3AEX	- / -19	2	✓ Closing fragment
06-01 03:27	20m	-11 / -2	9Y4DG	-22 / -10	3	✓ Full exchange observed
06-01 03:26	20m	-16 / -	SP1TJ	- / -8	2	Partial capture
06-01 03:24	20m	-13 / -	K5DZY	-13 / -10	2	✓ Closing observed
06-01 03:12	20m	-7 / -	OH1LA	- / -13	2	Partial capture
06-01 03:02	20m	-10 / -	KC3VKP	-15 / +1	3	✓ Closing observed
06-01 02:51	20m	-8 / -	SV1MOZ	- / -1	2	Partial capture
05-29 20:30	20m	- / -17	EA4T	-4 / -	2	✓ Closing fragment
05-28 04:18	20m	- / 0	KF0MSJ	-8 / -	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
032115  -4 2335  K4ISU IK2ZJR JN45 (x14)
041715 -18 2338  K4ISU F1PBZ RR73

20m

UTC    dB Audio  Message
025245  -8 2669  K4ISU DL1R JN58 (x2)
030130 -14 2532  N9UUR K4ISU RR73
031945 -18 2140  K4ISU K4YJ EM88
032545  -9 2280  K4ISU RD3FY KO85 (x4)
032915  +0  441  K4ISU IZ2QPP JN46 (x2)
033345 -21 1829  K4ISU OH2ZZ 73
042445 -11 2240  K4ISU RN6MA -16 (x2)
042945 -12  345  K4ISU I4IKW JN54
041100 -18 2276  KD9TWA K4ISU EM75

Decoder S/N history by band

Daily averages across messages associated with this profile as decoded at SO8OO.