When the CIA wanted to circumvent possible Chinese bugging of its offices in Beijing in the 1980s, it came up with a voice protector or “hush phone,” essentially two masks with tubes running between them. It worked, but no one
When the CIA wanted to circumvent possible Chinese bugging of its offices in Beijing in the 1980s, it came up with a voice protector or “hush phone,” essentially two masks with tubes running between them. It worked, but no one