[Milsurplus] Ship Radio Operators:

[Mike Morrow]

That's the first document I've seen that uses SSSS to indicate attack by submarine.  Everything else I've seen isSSS, sent:  dit dit dit (space) dit dit dit (space) dit dit ditThat contrasts withSOS, sent:  dit dit dit dah dah dah dit dit dit (one prosign, no spaces)
A WWII life boat 500 kHz transmitter made by Federal has selection for auto keying of SOS or SSS.
Hue, do you know the source of the document?  I also did not know of the A, R, M attack codes.  Interesting.
Mike / KK5F

-----Original Message-----

From: Hubert Miller 

Sent: Sep 14, 2020 3:16 AM
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