I recently learned of a series of YouTube videos that show a German machine that is alleged to be the voice behind Soviet cold war numbers stations. The videos, uploaded four years ago, show something that looks like a piece of electronic lab equipment that emits a sampled or synthesized voice rattling off a programmed sequence of numbers. According to the accompanying description, the voice comes from swappable program chips, and the machines are owned by a German spy-gadget collector.
For the uninitiated, numbers stations are shortwave broadcasters that transmit nothing but sequences of numbers read in a monotone voice, in any number of languages. It was long thought that the stations were sending coded instructions to spies and other foreign agents in the field, and recent evidence and declassified documents show this to be true. During the cold war they were nearly ubiquitous on the shortwave dial, and persisted after the fall of the Soviet Union. Though they are less common now than they were even twenty years ago, shortwave listeners can still find them relatively easily.
The machine in these videos speaks in Spanish and German, or can play morse code. It can be programmed manually through a number pad or by using a punched tape that looks like a miniature player-piano roll, clearly indicating that this is a piece of 1980s Soviet tech. Shots of the machine’s guts show Zilog Z80 microprocessors, which were popular CPUs for home and business microcomputers in the late 70s and early 80s. Curiously, all the parts, ports and the display are labeled in English.
The creator of the videos is a IT security professional from the Netherlands named Peter Staal, who has also given several lectures on the topic of numbers stations. One of his lectures from 2011 given at Delft University of Technology is available on YouTube. His PowerPoint slide deck is also available on SlideShare.