I hear that too, and was wondering what its correct meaning is. In my training materials -...- is an equal sign, or double hyphen: = It has a meaning, but I don't what it is unless maybe it is a QSO between engineers discussing mathematics. And I guess there is some fluidity and variation in the language. Colloquial to time and place as well perhaps. Maybe old timers hang on to former protocols and newer ops adopt new ways. Asian, Euro, N American differences too? And toss in some unofficial adoptions, like ending a conversation with dit dit. Or QRP ops sending regards as 72, rather than 73. Kind of an insider wink about their craft.