Russian G06 "German Lady" number station at 5136 kHz. A few minutes prior to the scheduled transmission "691, null, null" and then a test tone (possibly slow CW for the letters "T" and "V" ?) was sent, then at the scheduled time, a null message was transmitted:
G06 at 5126 kHz.
Earlier, I recorded this:
G06 at 5766 kHz.
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Curt / W9SPY
(Edited to correct spelling)