Spy Communication
Jack explains the process of communicating with the Russians as a spy and how it interfered with his normal job. He also talks about how the Russians communicated with him on a short wave radio using spoken digits in groups of five.In this clip
From this podcast

The Jordan Harbinger Show
286: Jack Barsky | Deep Undercover with a KGB Spy in America Part Two
Related Questions
How is information communicated in espionage according to Jack Barsky's experiences in the episode 286: Jack Barsky | Deep Undercover with a KGB Spy in America Part Two and the clip Spy Communication?
What standards exist for encryption in espionage communications as mentioned by Jack Barsky in the episode 286: Jack Barsky | Deep Undercover with a KGB Spy in America Part Two and the clip Spy Communication?