To nq4 - it will be nice if, in addition to the information Thomas writes about, you provide the reception QTH. All these parameters allow us to approximately predict the sender's area of interest.
When I returned to my interest in SWL, I was surprised that numbers stations still actively use HF to communicate with their agents, despite the omnipotent Internet and satellite communications.
Radio waves are like air, anyone can listen to them, but only the initiated know what it means.
Our humble work does some good, as evidenced by the large number of followers!
Best regards to all listeners!