JA5MHD — FT8 activity observed at SO8OO

DXCC entity inferred from callsign: Japan Most frequent locator attributed to this token: PM63

Receiver-side FT8 activity involving JA5MHD, decoded by SO8OO in southeastern Poland. 925 FT8 messages attributed to this token as transmitter, on 80m, 40m, 20m, across 68 UTC dates in the available aggregate history. Observed between 2026-06-06 and 2026-09-15.

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 925 FT8 messages attributed to JA5MHD as the transmitting token by decoded message structure across 68 UTC dates in the available aggregate history. The largest monitored-band total was 80 m (50%), followed by 40 m (48%) and 20 m (2%). Several six-hour UTC windows tied for the largest share (100%), so no unique busiest interval is claimed. Received S/N was mixed across SO8OO's weak, moderate and strong ranges; the estimated median was -12 dB.

Overview

925

Messages attributed

UTC dates decoded

171

Active 15-min windows

-12 dB

Estimated median S/N

Bands

80m · 464 40m · 444 20m · 17

First attributed message: 2026-06-06
Last attributed message: 2026-09-15 20:55 UTC

Observed FT8 message patterns

Attributed sample: 925 messages
Active dates: 68 UTC dates
Estimated median S/N: -12 dB
Estimated 10th-90th percentile: -22 to -2 dB
Recurring-pattern threshold: Met

SO8OO display ranges among successful decodes: weak (≤ -16 dB) 281, moderate (-15 to -9 dB) 359, strong (≥ -8 dB) 285.

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 JA5MHD in decoded directed-looking exchanges:

DL3MIB · Fed. Rep. of Germany ×2 HB9TOC · Switzerland ×2 A71QQ · Qatar ×2 IZ3ATV · Italy ×2 E73X · Bosnia-Herzegovina ×2 F5PBG · France ×2 IW4EGP · Italy ×2 LY2BSW · Lithuania ×2 OH3NXW · Finland ×2 OK2CLW · Czech Republic ×2 R3EDI · European Russia ×2 R7ZY · European Russia ×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 JA5MHD

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: PM63 · 156 decoded messages
SO8OO receiver locator: KN09VW
Locator-centre separation: 8,540 km (approx.)
Last such locator decoded: 2026-09-15 20:38 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	JA5MHD S/N	Counterpart	Counterpart S/N	Msgs	Capture
09-15 21:10	80m	- / -17	LZ123RF	+8 / -	3	Partial capture
09-15 20:55	80m	-9 / -17	SV7LWI	-7 / -17	3	✓ Full exchange observed
09-15 20:53	80m	-10 / -16	YO2MNZ	-1 / -17	4	✓ Full exchange observed
09-15 20:50	80m	-22 / -	OM7RU	- / -20	2	Partial capture
09-15 20:50	80m	- / -	YO2MNZ	+8 / -	2	Partial capture
09-15 20:42	80m	- / -17	LX2A	+4 / -	2	Partial capture
09-15 20:42	80m	-24 / -12	OH2NAG	-1 / -15	3	✓ Full exchange observed
09-15 20:35	80m	-24 / -	F5USK	-14 / -15	2	Partial capture
09-15 20:29	80m	-20 / -	LX2A	- / -12	3	Partial capture
09-15 20:21	80m	-17 / -	LX2A	- / -12	4	Partial capture
09-15 19:56	40m	-12 / -	RI1FJZ	- / -	15	Partial capture
09-15 19:39	40m	-11 / -	RI1FJZ	- / -	13	Partial capture
09-15 19:31	40m	-10 / -	RI1FJZ	- / -24	6	Partial capture
09-14 21:24	40m	- / -8	IW0HAC	-1 / -	3	✓ Closing fragment
09-14 21:18	40m	-16 / -11	IZ2DPX	+7 / -21	5	Partial capture
09-14 21:17	40m	-13 / -	YE4FHY	- / -8	2	✓ Closing fragment
09-14 21:15	40m	-12 / -	SP3GHC	- / -14	2	✓ Closing fragment
09-14 21:15	40m	-11 / -6	IT9PQU	-3 / -13	7	✓ Full exchange observed
09-14 21:10	40m	- / -13	HB9ELE	+6 / -	2	✓ Closing fragment
09-14 20:51	80m	- / -	G4IRN	+3 / -	2	Partial capture
09-14 20:01	80m	- / -10	SV9CVY	-2 / -	3	✓ Closing fragment
09-13 21:30	40m	- / -26	CT1FIU	-4 / -	3	Partial capture
09-13 21:25	40m	- / -26	CT1FIU	-7 / -	5	Partial capture
09-13 21:24	40m	-8 / -8	DH0GSU	-7 / -10	4	✓ Full exchange observed
09-13 21:19	40m	-18 / -	CX3RAN	- / -11	4	Partial capture
09-13 21:18	40m	-14 / -5	F5LQ	+6 / -11	4	✓ Full exchange observed
09-13 21:16	40m	-13 / -16	EB3JT	-7 / -14	5	✓ Full exchange observed
09-13 21:15	40m	-14 / -	YL2KF	- / -17	2	✓ Closing fragment
09-13 21:03	80m	- / -16	SP2LLP	+8 / -	2	✓ Closing fragment
09-13 20:54	80m	- / -9	S51DI	+10 / -	2	✓ Closing fragment
09-12 21:21	40m	-18 / -8	SQ8NA	-18 / -17	3	Partial capture
09-12 21:20	40m	-16 / -	PY2DN	- / -14	3	✓ Closing fragment
09-12 21:17	40m	- / -	G4FHL	+3 / -	5	Partial capture
09-12 21:16	40m	-15 / -	EH2PDA	- / -15	2	Partial capture
09-12 21:15	40m	-12 / -	G4CFS	+4 / -13	4	✓ Closing observed
09-12 21:14	40m	- / -	DL1SRS	-4 / -	2	Partial capture
09-12 21:13	40m	- / -3	TF4M	0 / -	2	✓ Closing fragment
09-12 21:09	40m	- / -7	EH2PDA	-9 / -	3	Partial capture
09-12 21:05	40m	-19 / -6	PA3EWP	-2 / -8	4	✓ Full exchange observed
09-12 21:04	40m	-17 / -7	F4EEJ	-4 / -10	7	✓ Full exchange observed
09-12 21:04	40m	- / -13	DF1OLS	+5 / -	12	Partial capture
09-11 21:06	80m	- / -	SP9LCW	+24 / -	3	Partial capture
09-11 21:03	80m	- / -	SP9LCW	+18 / -	2	Partial capture
09-11 21:02	80m	- / -13	GW8DX	+6 / -	2	Partial capture
09-11 20:53	80m	- / -17	OH2BVT	0 / -	2	✓ Closing fragment
09-11 20:12	80m	- / -	IK0SHH	+2 / -	6	Partial capture
09-11 20:05	80m	- / -23	R2EC	+11 / -	2	✓ Closing fragment
09-10 21:29	40m	0 / -	R5AT	- / -8	2	✓ Closing fragment
09-10 21:28	40m	0 / 0	DA1EA	+10 / -7	4	✓ Full exchange observed
09-10 21:27	40m	- / -	EI4FNB	-8 / -	4	Partial capture

Recent FT8 messages decoded at SO8OO

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

80m

UTC    dB Audio  Message
204315  +8 1975  JA5MHD LX2A -17
205015  +8 2764  JA5MHD YO2MNZ KN15
205030 -24 1859  OM7RU JA5MHD -20
205045  +8 2764  JA5MHD YO2MNZ KN15
205100 -19 1859  OM7RU JA5MHD -20
205330 -10 2762  YO2MNZ JA5MHD -17 (x2)
205415  -3 2221  JA5MHD YO2MNZ R-16 (x2)
205530  -9 2762  SV7LWI JA5MHD -17
205615  -7 2001  JA5MHD SV7LWI R-17 (x2)
211030  +9 1259  JA5MHD LZ123RF R-17 (x3)

40m

UTC    dB Audio  Message
195645 -18 1577  RI1FJZ JA5MHD PM63 (x15)

160m

UTC    dB Audio  Message
205545 +18  513  JA5MHD DJ7M JN49 (x5)
204315  +9 2061  JA5MHD LY7M R-17 (x2)
201245 -20 1703  JA5MHD F4EUF JN39
202145  +6 1821  JA5MHD OK1TP R-09 (x2)

20m

UTC    dB Audio  Message
230030  -5 1054  JA5MHD S57LU 73
233100 -16 1579  JA5MHD 7Z1CZ -07 (x2)
233745  -6  601  JA5MHD 7Z1BQ -15 (x4)
225715 -19 2313  JA5MHD IZ5MJO R-07
225715  +4 2091  JA5MHD 9A7W R+12 (x3)
225845 -14 2313  JA5MHD IZ5MJO R-07
225915 +10 2780  JA5MHD IZ3ATV JN55 (x3)

10m

UTC    dB Audio  Message
075815 -19 1558  JA5MHD IU1QYF JN44
080145 -11 2651  JA5MHD G4IFX IO91
080415 -16 2288  JA5MHD OK1AWC JO70 (x2)
080515  -6 1194  JA5MHD DL8TV JN49
080915  -4  290  JA5MHD DL9KAR JO30
080930  +0 1067  JA5MHD DL3MIB R-10
080945  -4  290  JA5MHD DL9KAR JO30
081000  +3 1067  JA5MHD DL3MIB 73
081315  -8 2016  JA5MHD F5MYH R-07 (x2)
081445  -6  521  JA5MHD A92GE R-16 (x2)
083815  +7 2435  JA5MHD HB9TOC R-16 (x2)

60m

UTC    dB Audio  Message
195845  -3 1837  JA5MHD 9A4ZM JN86 (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.

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