DH4TOM — FT8 activity observed at SO8OO

DXCC entity inferred from callsign: Fed. Rep. of Germany Most frequent locator attributed to this token: JO54

Receiver-side FT8 activity involving DH4TOM, decoded by SO8OO in southeastern Poland. 31 FT8 messages attributed to this token as transmitter, on 20m, 10m, across 3 UTC dates in the available aggregate history. Observed between 2026-06-26 and 2026-08-09.

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 31 FT8 messages attributed to DH4TOM as the transmitting token by decoded message structure across 3 UTC dates in the available aggregate history. The largest monitored-band total was 20 m (94%), followed by 10 m (6%). Several six-hour UTC windows tied for the largest share (81%), so no unique busiest interval is claimed. Most successfully decoded messages attributed to this token fell in SO8OO's strong S/N range (77%); the estimated median was -3 dB.

Overview

Messages attributed

UTC dates decoded

Active 15-min windows

-3 dB

Estimated median S/N

Bands

20m · 29 10m · 2

First attributed message: 2026-06-26
Last attributed message: 2026-08-09 14:42 UTC

Observed FT8 message patterns

Attributed sample: 31 messages
Active dates: 3 UTC dates
Estimated median S/N: -3 dB
Estimated 10th-90th percentile: -11 to +9 dB
Recurring-pattern threshold: Met

SO8OO display ranges among successful decodes: weak (≤ -16 dB) 2, moderate (-15 to -9 dB) 5, strong (≥ -8 dB) 24.

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 DH4TOM in decoded directed-looking exchanges:

DC5IU · Fed. Rep. of Germany DF6JF · Fed. Rep. of Germany F1PSX · France G8IXM · England JA0FOX · Japan OH1LA · Finland RW9HSB · Asiatic Russia UB8CPH · Asiatic Russia UB8CQC/P · Asiatic Russia W5XO · United States

Most frequent locator attributed to DH4TOM

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: JO54 · 11 decoded messages
SO8OO receiver locator: KN09VW
Locator-centre separation: 892 km (approx.)
Last such locator decoded: 2026-08-09 14:38 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	DH4TOM S/N	Counterpart	Counterpart S/N	Msgs	Capture
08-09 14:42	20m	+8 / -	UB8CQC/P	- / -15	2	✓ Closing fragment
08-09 14:38	20m	+10 / -	JA0FOX	- / -9	4	✓ Closing fragment
07-06 08:33	20m	+1 / -	G8IXM	- / -1	2	✓ Closing fragment
07-06 08:32	20m	+4 / -	DC5IU	- / -11	2	✓ Closing fragment
07-06 08:32	20m	0 / -	DL9KM	-14 / -8	4	Partial capture
07-06 08:31	20m	-6 / -	OH1LA	- / -7	2	✓ Closing fragment
07-06 08:04	20m	0 / -	R0AH	- / -	2	Partial capture
07-06 08:02	20m	-1 / -	RW9HSB	- / -3	3	✓ Closing fragment
06-26 08:29	20m	-10 / -	W5XO	- / -16	3	✓ Closing fragment
06-26 08:25	20m	-8 / -	DF6JF	- / -3	2	✓ Closing fragment
06-26 08:23	20m	-8 / -	F1PSX	- / -13	2	✓ Closing fragment

Recent FT8 messages decoded at SO8OO

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

20m

UTC    dB Audio  Message
083215  -2 2675  OH1LA DH4TOM RR73
083230 -14 2332  DH4TOM DL9KM JN68
083245  +3 2675  DC5IU DH4TOM -11 (x2)
083330 -15 2332  DH4TOM DL9KM JN68
083345  +2 2674  G8IXM DH4TOM -01 (x2)
083430 -12 2332  DH4TOM DL9KM JN68
083445  +0 2675  DL9KM DH4TOM -08
143815  +7 2868  JA0FOX DH4TOM JO54 (x4)
144215 +10 2947  UB8CQC/P DH4TOM R-15 (x2)

10m

UTC    dB Audio  Message
080700 -24 1579  CQ DH4TOM JO54 (x2)

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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