I found this 2012 listening report on the Quebec amateur club website. It involves CW transmission by the Brazilian Navy at the same frequency of 16976 kHz.
https://craq.club/files/documents/Archives/numeriques.pdf
Is it just a coincidence that our mysterious CW station was reported by Brazil’s SWL?
We have obtained the following content: Google translation on radio transmitted French reports and Portuguese language books and correction of some hypothetical errors:
This is a small piece of weather report sent by PWZ (Brazilian Navy) in packer I.
……AREA VENT.
WAVES 5/6 with Burst 7. WAVES of
W/sw 1.5/2.5 pass5/2.5 no
REST NW/SW 4/5 WITH BLAST HANGING AROUND
Se/ne 3/4 southwest RESA. PASSAND5 WAVES IN THE SOUTHWEST OF THE AREA.
NORTHERN OCEAN AREA
WIND SE/E South of ECUADOR and E/NE 3/4 before the area.
QRU/ZKM QRU/ZKM QRU/ZKM
Rio de Janeiro Navy message ended at packer I (16976 kHz on 04/30/2012)
Post time: Jun-11-2021