NIL HEARDRECEPTION LOG

VLF submarine band 17.6-20.0 kHz (RDL, HWU, GBZ chord)

tier A · carrier

17.3 kHz USB · 2026-10-03 14:54:49Z · 09:30 · received at Heppen, Limburg, Belgium

Spectrogram of VLF submarine band 17.6-20.0 kHz (RDL, HWU, GBZ chord), 17.3 kHz USB, 2026-10-03 14:54:49Z, 09:30: carrier 100% · tone 700 Hz
spectrogram 0–6.0 kHz · analysis blocks: carrier
loop [ ] · speed in the player bar · deep link #t=seconds ⤓ FLAC 9.0 MB ⤓ Opus 2261 kB { }
What was heard
carrier 100% · tone 700 Hz — dominant tone 700 Hz. Machine description of the sound by the rig's classifier; it sorts, it does not certify a station.
Receiver
KiwiSDR, Heppen, Limburg, Belgium (JO21oc) · Longwire 54m top 70m above sealevel · reported SNR 35 dB — thanks to the operator. Receivers
Provenance
sha256 a3be81c524cb018392599f0edd85362307b6a288647dd6c3d9301935973a0c69
source 09:30 WAV, 12000 Hz mono
kiwirecorder.py (jks-prv/kiwiclient v1.11) · rig item 2026-10-03T1454Z-17.3-vlf-17300
Heard in the record
— linked once the record exists.
Licence
CC BY 4.0 — credit NIL HEARD / Reception Log. The recording is ours; the transmission is somebody else's. Descriptions describe sound, never content — why.
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